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FGSD12SR6012*A
3-14.4Vdc Input, 12A, 0.45-5.5Vdc Output
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Data Sheet
The Digital Tomodachi Series of non-isolated dc-dc
converters deliver exceptional electrical and thermal
performance in DOSA based footprints for
Point-of-Load converters. Operating from a
3.0Vdc-14.4Vdc input, these are the converters of
choice for Intermediate Bus Architecture (IBA) and
Distributed Power Architecture applications that
require high efficiency, tight regulation, and high
reliability in elevated temperature environments with
low airflow. The PMBus interface supports a range of
commands to both control and monitor the module.
The module also includes the Tunable Loop™
feature that allows the user to optimize the dynamic
response of the converter to match the load with
reduced amount of output capacitance leading to
savings on cost and PWB area.
The FGSD12SR6012*A converter of the Tomodachi
Series delivers 12A of output current at a tightly
regulated programmable and PMBus control output
voltage of 0.45Vdc to 5.5Vdc. The thermal
performance of the FGSD12SR6012*A is
best-in-class: Little derating is needed up to 85,
under natural convection.
Applications
Intermediate Bus Architecture
Telecommunications
Data/Voice processing
Distributed Power Architecture
Computing (Servers, Workstations)
Test Equipments
Features
Compliant to RoHS II EU Directive 2011/65/EC
Delivers up to 12A (66W)
High efficiency, no heatsink required
Negative and Positive ON/OFF logic
DOSA based
Small size: 12.2 x 12.2 x 8.5mm
(0.48 in x 0.48 in x 0.335 in)
Tape & reel packaging
Programmable output voltage from 0.6V to 5.5V
via external resistor. Digitally adjustable down to
0.45Vdc
Digital interface through the PMBus™ # protocol
Tunable Loop™ to optimize dynamic output
voltage response
Flexible output voltage sequencing
EZ-SEQUENCE
Power Good signal
Fixed switching frequency with capability of
external synchronization
Auto-reset output over-current protection
Remote ON/OFF
Ability to sink and source current
No minimum load required
Start up into pre-biased output
UL* 60950-1 2nd Ed. Recognized, CSA C22.2 No.
60950-1-07 Certified, and VDE (EN60950-1 2nd Ed.)
(Pending)
ISO** 9001 and ISO 14001 certified manufacturing
facilities
* UL is a registered trademark of Underwriters Laboratories, Inc.
CSA is a registered trademark of Canadian Standards Association.
VDE is a trademark of Verband Deutscher Elektrotechniker e.V.
** ISO is a registered trademark of the International Organization of Standards
# The PMBus name and logo are registered trademarks of the System Management Interface Forum (SMIF)
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Data Sheet
Absolute Maximum Ratings
Stresses in excess of the absolute maximum ratings may lead to degradation in performance and reliability of
the converter and may result in permanent damage.
Electrical Specifications
All specifications apply over specified input voltage, output load, and temperature range, unless otherwise
noted.
PARAMETER NOTES MIN TYP MAX UNITS
ABSOLUTE MAXIMUM RATINGS1
Input Voltage Continuous -0.3 15 Vdc
SEQ, SYNC, Vs+ 7 Vdc
CLK, DATA, SMBALERT 3.6 Vdc
Operating Temperature Ambient temperature -40 85 °C
Storage Temperature -55 125 °C
Output Voltage 0.45 5.5 Vdc
PARAMETER NOTES MIN TYP MAX UNITS
INPUT CHARACTERISTICS
Operating Input Voltage Range 3.0 14.4 Vdc
Maximum Input Current Vin=3V to 14V, Io-max 9 Adc
Input Stand-by Current Vin=12V, module disabled 6.5 mA
Input No Load Current Vout=5.0V 85 mA
Vout=0.6V 52 mA
Inrush Transient, I2t 1 A2s
Input Reflected-Ripple Current Peak-to-peak (5Hz to 20MHz, 1uH
source impedance; Vin=0 to 14V, Io-max 400 mAp-p
Input Ripple Rejection (120Hz) -55 dB
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FGSD12SR6012*A
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Data Sheet
Electrical Specifications (Continued)
1 External capacitors may require using the new Tunable LoopTM feature to ensure that the module is stable as well as
getting the best transient response. See the Tunable LoopTM section for details.
PARAMETER NOTES MIN TYP MAX UNITS
OUTPUT CHARACTERISTICS
Output Voltage Set Point With 0.1% tolerance for external resistor
used to set output voltage -1.0 +1.0 %Vout
Output Voltage Range
(Over all operating input voltage,
resistive load and temperature
conditions until end of life)
-3.0 +3.0 %Vout
Adjustment Range
(selected by an external resistor)
Some output voltages may not be
possible depending on the input voltage
– see feature description section
0.6 5.5 Vdc
PMBus Adjustable Output Voltage Range -25 +25 %Vout
PMBus Output Voltage Adjustment Step Size 0.4 %Vout
Remote Sense Range 0.5 Vdc
Output Regulation (for Vo 2.5Vdc) Line (Vin = min to max) 0.4 % Vout
Load (Io = min to max) 10 mV
Output Regulation (for Vo < 2.5Vdc) Line (Vin = min to max) 5 mV
Load (Io = min to max) 10 mV
Temperature (Ta = min to max) 0.4 % Vout
Output Ripple and Noise Vin=12V, Io= min to max, Co =
0.1uF+22uF ceramic capacitors
Peak to Peak 5MHz to 20MHz bandwidth 50 100 mVp-p
RMS 5MHz to 20MHz bandwidth 20 38 mVrms
External Load Capacitance 1 Plus full load (resistive) %
Without the Tunable Loop ESR 1m 22 47 uF
With the Tunable Loop ESR 0.15m 22 1,000 uF
ESR 10m 22 5,000 uF
Output Current Range (in either sink or source mode) 0 12 Adc
Output Current Limit Inception (Hiccup mode) Current limit does not operate in sink
mode 130 % Io-max
Output Short-Circuit Current Vo 250mV, Hiccup mode 0.92 Arms
Efficiency
Vin = 12Vdc, Ta = 25°C, Io = max Vout=5.0Vdc 95.4 %
Vout=3.3Vdc 93.6 %
Vout=2.5Vdc 92.2 %
Vout=1.8Vdc 89.9 %
Vout=1.2Vdc 86.0 %
Vout=0.6Vdc 76.4 %
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FGSD12SR6012*A
3-14.4Vdc Input, 12A, 0.45-5.5Vdc Output
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Data Sheet
Electrical Specifications (Continued)
General Specifications
Feature Specifications
PARAMETER NOTES MIN TYP MAX UNITS
Switching Frequency 600 kHz
Frequency Synchronization
Synchronization Frequency Range 510 720 kHz
High Level Input Voltage 2.0 V
Low Level Input Voltage 0.4 V
Input Current, SYNC 100 nA
Minimum Pulse Width, SYNC 100 nS
Maximum SYNC rise time 100 nS
PARAMETER NOTES MIN TYP MAX UNITS
Calculated MTBF Io = 0.8 * Io-max, Ta = 40°C
Telecordia Issue 2 Method 1 Case 3 21,774,843 Hours
Weight 2.23(0.079) g (oz.)
PARAMETER NOTES MIN TYP MAX UNITS
ON/OFF Signal Interface Vin = min to max, open collector or
equivalent, Signal reference to GND
Positive Logic
Logic High (Module ON)
Input High Current 1 mA
Input High Voltage 2.0 Vin-max V
Logic Low (Module OFF)
Input Low Current 1 mA
Input Low Voltage -0.2 0.6 V
Negative Logic
On/Off pin is open collector/drain logic input
with external pull-up resistor; signal
reference to GND
Logic High (Module OFF)
Input High Current 1 mA
Input High Voltage 2.0 Vin-max V
Logic Low (Module ON)
Input Low Current 10 uA
Input Low Voltage -0.2 0.6 V
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3-14.4Vdc Input, 12A, 0.45-5.5Vdc Output
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Data Sheet
Feature Specifications
* Over temperature Warning – Warning may not activate before alarm and unit may shutdown before warning
PARAMETER NOTES MIN TYP MAX UNITS
Turn-On Delay Time Vin = Vin-nom, Io = Io-max , Vo to within
±1% of steady state
Case 1: On/Off input is enabled and
then input power is applied
delay from instant at which Vin =
Vin-min until Vo = 10% of Vo-set) 1.1 ms
Case 2: Input power is applied for at least
one second and then the On/Off input
is enabled
delay from instant at which Von/Off is
enabled until Vo = 10% of Vo-set 700 us
Output voltage Rise time time for Vo to rise from 10% of Vo-set to
90% of Vo-set 3.1 ms
Output voltage overshoot with or without
maximum external capacitance
Ta = 25oC, Vin = Vin-min to Vin-max,
Io = Io-min to Io-max 3.0 %Vout
Over Temperature Protection (See Thermal Considerations section) 120 °C
PMBus Over Temperature Warning Threshold
* 130 °C
Tracking Accuracy Vin-min to Vom-max, Io-min to Io-max,
VSEQ < Vo
Power-Up: 2V/ms 100 mV
Power-Down: 2V/ms 100 mV
Input Under Voltage Lockout
Turn-on Threshold 2.475 3.025 Vdc
Turn-off Threshold 2.25 2.75 Vdc
Hysteresis 0.25 Vdc
PMBus Adjustable Input Under Voltage
Lockout Thresholds 2.5 14 Vdc
Resolution of Adjustable Input Under
Voltage Threshold 500 mV
PGOOD (Power Good)
Signal Interface Open Drain,
Vsupply 5VDC
Overvoltage threshold for PGOOD ON 108 %Vout
Overvoltage threshold for PGOOD OFF 110 %Vout
Undervoltage threshold for PGOOD ON 92 %Vout
Undervoltage threshold for PGOOD OFF 90 %Vout
Pulldown resistance of PGOOD pin 50
Sink current capability into PGOOD pin 5 mA
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FGSD12SR6012*A
3-14.4Vdc Input, 12A, 0.45-5.5Vdc Output
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Data Sheet
Digital Interface Specifications
PARAMETER NOTES MIN TYP MAX UNITS
PMBus Signal Interface Characteristics
Input High Voltage (CLK, DATA) 2.1 3.6 V
Input Low Voltage (CLK, DATA) 0.8 V
Input high level current (CLK, DATA) -10 10 uA
Input low level current (CLK, DATA) -10 10 uA
Output Low Voltage (CLK, DATA, SMBALERT#) IOUT=2mA 0.4 V
Output high level open drain leakage current (DATA,
SMBALERT#) VOUT=3.6V 0 10 uA
Pin capacitance 0.7 pF
PMBus Operating frequency range Slave Mode 10 400 kHz
Data hold time Receive Mode 0 nS
Transmit Mode 300 nS
Data setup time 250 nS
Measurement System Characteristics
Read delay time 153 192 231 us
Output current measurement range 0 18 A
Output current measurement resolution 62.5 mA
Output current measurement gain accuracy (at 25°C) ±5 %
Output current measurement offset 0.1 A
Vout measurement range 0 5.5 V
Vout measurement resolution 15.625 mV
Vout measurement accuracy -15 15 %
Vout measurement offset -3 3 %
Vinmeasurement range 3 14.4 V
Vin measurement resolution 32.5 mV
Vin measurement accuracy -15 15 %
Vin measurement offset -5.5 1.4 LSB
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Data Sheet
Design Considerations
Input Filtering
The FGSD12SR6012*A converter should be
connected to a low ac-impedance source. A highly
inductive source can affect the stability of the module.
An input capacitance must be placed directly
adjacent to the input pin of the module, to minimize
input ripple voltage and ensure module stability.
To minimize input voltage ripple, ceramic capacitors
are recommended at the input of the module. Fig-1
shows the input ripple voltage for various output
voltages at 12A of load current with 2x22uF or
3x22uF ceramic capacitors and an input of 12V.
Output Filtering
The FGSD12SR6012*A is designed for low output
ripple voltage and will meet the maximum output
ripple specification with 0.1uF ceramic and 22uF
ceramic capacitors at the output of the module.
However, additional output filtering may be required
by the system designer for a number of reasons.
First, there may be a need to further reduce the
output ripple and noise of the module. Second, the
dynamic response characteristics may need to be
customized to a particular load step change.
To reduce the output ripple and improve the dynamic
response to a step load change, additional
capacitance at the output can be used. Low ESR
polymer and ceramic capacitors are recommended to
improve the dynamic response of the module. Fig-2
provides output ripple information for different
external capacitance values at various Vo and a full
load current of 12A. For stable operation of the
module, limit the capacitance to less than the
maximum output capacitance as specified in the
electrical specification table. Optimal performance of
the module can be achieved by using the Tunable
Loop™ feature described later in this data sheet.
Safety Consideration
For safety agency approval the power module must
be installed in compliance with the spacing and
separation requirements of the end-use safety
agency standards, i.e., UL 60950-1 2nd, CSA C22.2
No. 60950-1-07, DIN EN 60950-1:2006 + A11
(VDE0805 Teil 1 + A11):2009-11; EN 60950-1:2006
+ A11:2009-03.
For the converter output to be considered meeting
the requirements of safety extra-low voltage (SELV),
the input must meet SELV requirements. The power
module has extra-low voltage (ELV) outputs when all
inputs are ELV.
The input to these units is to be provided with a
slow-blow fuse with a maximum rating of 15 A in the
positive input lead.
Fig-1: Input ripple voltage for various output
voltages with 2x22uF or 3x22uF ceramic
capacitors at the input (12A load). Input voltage
is 12V.
50
100
150
200
250
0.51.52.53.54.5
R ipple ( mVp-p)
Output Voltage(Volts)
2x22uF
3x22uF
Fig-2: Output ripple voltage for various output
voltages with external 1x22uF, 1x47uF, 2x47uF
or 4x47uF ceramic capacitors at the output (12A
load). Input voltage is 12V.
0
10
20
30
40
50
60
0.5 1.5 2.5 3.5 4.5
R ipple ( mVp-p)
Output Voltage(Volts)
1x22uF Ext Cap
1x47uF Ext Cap
2x47uF Ext Cap
4x47uF Ext Cap
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Data Sheet
Analog Feature Descriptions
Remote On/Off
The module can be turned ON and OFF either by
using the ON/OFF pin (Analog interface) or through
the PMBus interface (Digital). The module can be
configured in a number of ways through the PMBus
interface to react to the two ON/OFF inputs:
Module ON/OFF can be controlled only through
the analog interface (digital interface ON/OFF
commands are ignored)
Module ON/OFF can be controlled only through
the PMBus interface (analog interface is ignored)
Module ON/OFF can be controlled by either the
analog or digital interface
The default state of the module (as shipped from the
factory) is to be controlled by the analog interface
only. If the digital interface is to be enabled, or the
module is to be controlled only through the digital
interface, this change must be made through the
PMBus. These changes can be made and written to
non-volatile memory on the module so that it is
remembered for subsequent use.
Analog ON/OFF
The FGSD12SR6012*A power modules feature an
On/Off pin for remote On/Off operation. Two On/Off
logic options are available. In the Positive Logic
On/Off option, (device code suffix “P” - see Part
Number System), the module turns ON during a logic
High on the On/Off pin and turns OFF during a logic
Low. With the Negative Logic On/Off option, (device
code suffix “N” - see Part Number System), the
module turns OFF during logic High and ON during
logic Low. The On/Off signal should be always
referenced to ground. For either On/Off logic option,
leaving the On/Off pin disconnected will turn the
module ON when input voltage is present.
For positive logic modules, the circuit configuration
for using the On/Off pin is shown in Fig-3. When the
external transistor Q2 is in the OFF state, the internal
transistor Q1 is turned ON, and the internal PWM
#Enable signal is pulled low causing the module to be
ON. When transistor Q2 is turned ON, the On/Off pin
is pulled low and the module is OFF. A suggested
value for Rpullup is 20k.
For negative logic On/Off modules, the circuit
configuration is shown in Fig-4. The On/Off pin
should be pulled high with an external pull-up resistor
(suggested value for the 3V to 14V input range is
20K). When transistor Q2 is in the OFF state, the
On/Off pin is pulled high, transistor Q1 is turned ON
and the module is OFF. To turn the module ON, Q2
is turned ON pulling the On/Off pin low, turning
transistor Q1 OFF resulting in the PWM Enable pin
going high.
Digital ON/OFF
Please see the Digital Feature Descriptions section.
Monotonic Start-up and Shut-down
The module has monotonic start-up and shutdown
behavior for any combination of rated input voltage,
output current and operating temperature range.
Startup into Pre-biased Output
The module can start into a prebiased output as long
as the prebias voltage is 0.5V less than the set output
voltage.
Fig-3: Circuit configuration for using positive
On/Off logic.
10K
Q2
22K
Q1
22K
Rpullup
+3.3
V
+VIN
GND
+
_
VON/OFF
ON/OFF
IENABLE
MODULE
Fig-4: Circuit configuration for using negative
On/Off logic.
10K
Q2
22K
Q1
22K
Rpullup
+3.3
V
+VIN
GND
_
+
I
ON/OFF
V
ON/OFF ENABLE
MODULE
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Data Sheet
Analog Output Voltage Programming
The output voltage of the module is programmable to
any voltage from 0.6dc to 5.5Vdc by connecting a
resistor between the Trim and SIG_GND pins of the
module. Certain restrictions apply on the output
voltage set point depending on the input voltage.
These are shown in the Output Voltage vs. Input
Voltage Set Point Area plot in Fig-5. The Upper
Limit curve shows that for output voltages lower than
1V, the input voltage must be lower than the
maximum of 14.4V. The Lower Limit curve shows
that for output voltages higher than 0.6V, the input
voltage needs to be larger than the minimum of 3V.
Without an external resistor between Trim and
SIG_GND pins, the output of the module will be
0.6Vdc. To calculate the value of the trim resistor,
Rtrim for a desired output voltage, should be as per
the following equation:
Rtrim is the external resistor in kohm
Vo-req is the desired output voltage
Note that the tolerance of a trim resistor will affect the
tolerance of the output voltage. Standard 1% or 0.5%
resistors may suffice for most applications; however,
a tighter tolerance can be obtained by using two
resistors in series instead of one standard value
resistor.
Table 1 provides RTRIM values required for some
common output voltages.
Table 1: Trim Resistor Value
VO-REG [V] RTRIM [k]
0.6 Open
0.9 40
1.0 30
1.2 20
1.5 13.33
1.8 10
2.5 6.316
3.3 4.444
5.0 2.727
Digital Output Voltage Adjustment
Please see the Digital Feature Descriptions section.
Remote Sense
The power module has a Remote Sense feature to
minimize the effects of distribution losses by
regulating the voltage between the sense pins (VS+
and VS-). The voltage drop between the sense pins
and the VOUT and GND pins of the module should
not exceed 0.5V.
Analog Voltage Margining
Output voltage margining can be implemented in the
module by connecting a resistor, Rmargin-up, from
the Trim pin to the ground pin for margining-up the
output voltage and by connecting a resistor,
Rmargin-down, from the Trim pin to output pin for
margining-down. Fig-7 shows the circuit configuration
for output voltage margining. The POL Programming
Tool, available at www.fdk.com under the Downloads
section, also calculates the values of Rmargin-up and
]k[
0.6)-(V
12
R
REQ-O
TRIM Ω
Fig-5: Output Voltage vs. Input Voltage Set
Point Area plot showing limits where the output
voltage can be set for different input voltages.
Fig-6: Output Voltage vs. Input Voltage Set
Point Area plot showing limits where the output
voltage can be set for different input voltages.
Caution – Do not connect SIG_GND to
GND elsewhere in the layout.
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Data Sheet
Rmargin-down for a specific output voltage and %
margin. Please consult your local FDK FAE for
additional details.
Digital Output Voltage Margining
Please see the Digital Feature Descriptions section.
Output Voltage Sequencing
The power module includes a sequencing feature,
EZSEQUENCE that enables users to implement
various types of output voltage sequencing in their
applications. This is accomplished via an additional
sequencing pin. When not using the sequencing
feature, leave it unconnected.
The voltage applied to the SEQ pin should be scaled
down by the same ratio as used to scale the output
voltage down to the reference voltage of the module.
This is accomplished by an external resistive divider
connected across the sequencing voltage before it is
fed to the SEQ pin as shown in Fig-8. In addition, a
small capacitor (suggested value 100pF) should be
connected across the lower resistor R1.
For all Tomodachi modules, the minimum
recommended delay between the ON/OFF signal and
the sequencing signal is 10ms to ensure that the
module output is ramped up according to the
sequencing signal. This ensures that the module
soft-start routine is completed before the sequencing
signal is allowed to ramp up.
When the scaled down sequencing voltage is applied
to the SEQ pin, the output voltage tracks this voltage
until the output reaches the set-point voltage. The
final value of the sequencing voltage must be set
higher than the set-point voltage of the module. The
output voltage follows the sequencing voltage on a
one-to-one basis. By connecting multiple modules
together, multiple modules can track their output
voltages to the voltage applied on the SEQ pin.
The module’s output can track the SEQ pin signal
with slopes of up to 0.5V/msec during power-up or
power-down.
To initiate simultaneous shutdown of the modules,
the SEQ pin voltage is lowered in a controlled
manner. The output voltage of the modules tracks the
voltages below their set-point voltages on a
one-to-one basis. A valid input voltage must be
maintained until the tracking and output voltages
reach ground potential.
Note that in all digital Tomodachi series of modules,
the PMBus Output Undervoltage Fault will be tripped
when sequencing is employed. This will be detected
using the STATUS_WORD and STATUS_VOUT
PMBus commands. In addition, the SMBALERT#
signal will be asserted low as occurs for all faults and
warnings. To avoid the module shutting down due
to the Output Undervoltage Fault, the module must
be set to continue operation without interruption as
the response to this fault (see the description of the
PMBus command VOUT_UV_FAULT_RESPONSE
for additional information).
Fig-7: Circuit Configuration for margining Output
Voltage.
Fig-8: Circuit showing connection of the
sequencing signal to the SEQ pin.
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Data Sheet
Over-Current Protection
To provide protection in a fault (output overload)
condition, the unit is equipped with internal
current-limiting circuitry and can endure current
limiting continuously. At the point of current-limit
inception, the unit enters hiccup mode. The unit
operates normally once the output current is brought
back into its specified range.
Digital Adjustable Overcurrent Warning
Please see the Digital Feature Descriptions section.
Over-Temperature Protection
To provide protection in a fault condition, the unit is
equipped with a thermal shutdown circuit. The unit
will shut down if the over-temperature threshold of
150°C (typ) is exceeded at the thermal reference
point Tref. Once the unit goes into thermal shutdown
it will then wait to cool before attempting to restart.
Digital Temperature Status via PMBus
Please see the Digital Feature Descriptions section.
Digitally Adjustable Output Over and Under
Voltage Protection
Please see the Digital Feature Descriptions section.
Input Under-Voltage Lockout (UVLO)
At input voltages below the input under-voltage
lockout limit, the module operation is disabled. The
module will begin to operate at an input voltage
above the under-voltage lockout turn-on threshold.
Digitally Adjustable Input Undervoltage
Lockout
Please see the Digital Feature Descriptions section.
Digitally Adjustable Power Good Thresholds
Please see the Digital Feature Descriptions section.
Synchronization
The module switching frequency can be
synchronized to a signal with an external frequency
within a specified range. Synchronization can be
done by using the external signal applied to the
SYNC pin of the module as shown in Fig-9, with the
converter being synchronized by the rising edge of
the external signal. The Electrical Specifications table
specifies the requirements of the external SYNC
signal. If the SYNC pin is not used, the module
should free run at the default switching frequency. If
synchronization is not being used, connect the
SYNC pin to GND.
Measuring Output Current, Output Voltage
and Input Voltage
Please see the Digital Feature Descriptions section.
Dual Layout
Identical dimensions and pin layout of Analog and
Digital Tomodachi modules permit migration from
one to the other without needing to change the
layout. To support this, 2 separate Trim Resistor
locations have to be provided in the layout. As shown
in Fig. 10, for the digital modules, the resistor is
connected between the TRIM pad and SGND and in
the case of the analog module it is connected
between TRIM and GND.
Fig-9: External source connections to
synchronize switching frequency of the module.
Fig-10: Connections to support either Analog or
Digital Tomodachi on the same layout.
MODULE
Rtrim1
for
Digital
GND(Pin 7)
SIG_GND
TRIM Rtrim2
for
A
nalog
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Data Sheet
Tunable Loop™
The module has a feature that optimizes transient
response of the module called Tunable Loop™
External capacitors are usually added to the output of
the module for two reasons: to reduce output ripple
and noise (see Fig-2) and to reduce output voltage
deviations from the steady-state value in the
presence of dynamic load current changes. Adding
external capacitance however affects the voltage
control loop of the module, typically causing the loop
to slow down with sluggish response. Larger values
of external capacitance could also cause the module
to become unstable.
The Tunable Loop™ allows the user to externally
adjust the voltage control loop to match the filter
network connected to the output of the module. The
Tunable Loop™ is implemented by connecting a
series R-C between the SENSE and TRIM pins of the
module, as shown in Fig-11. This R-C allows the user
to externally adjust the voltage loop feedback
compensation of the module.
Recommended values of RTUNE and CTUNE for
different output capacitor combinations are given in
Table 2. Table 2 shows the recommended values of
RTUNE and CTUNE for different values of ceramic output
capacitors up to 1000uF that might be needed for an
application to meet output ripple and noise
requirements. Selecting RTUNE and CTUNE according to
Table 2 will ensure stable operation of the module.
In applications with tight output voltage limits in the
presence of dynamic current loading, additional
output capacitance will be required. Table 3 lists
recommended values of RTUNE and CTUNE in order to
meet 2% output voltage deviation limits for some
common output voltages in the presence of a 6A to
12A step change (50% of full load), with an input
voltage of 12V.
Please contact your FDK technical representative to
obtain more details of this feature as well as for
guidelines on how to select the right value of external
R-C to tune the module for best transient
performance and stable operation for other output
capacitance values or input voltages other than 12V.
Table 2: General recommended value of RTUNE
and CTUNE for Vin=12V and various external
ceramic capacitor combinations.
Co 1x47uF 2x47uF 4x47uF 6x47uF 10x47uF
RTUNE 330 330 330 330 220
CTUNE 100pF 560pF 1500pF 2200pF 10nF
Co 20x47uF
RTUNE 180
CTUNE 6800pF
Table 3: Recommended values of RTUNE and
CTUNE to obtain transient deviation of 2% of Vout
for a 6A step load with Vin=12V.
Vo 5V 3.3V 2.5V 1.8V 1.2V 0.6V
Co 5x47uF
1x47uF
+
330uF
Polymer
3x47uF
+
330uF
Polymer
1x47uF
+
2x330uF
Polymer
1x47uF
+
3x330uF
Polymer
3x47uF
+
6x330uF
Polymer
RTUNE 330 330 270 270 220 180
CTUNE 1500pF 2700pF 3300pF 5600pF 10nF 47nF
V99mV 58mV 47mV 34mV 24mV 12mV
Fig-11: Circuit diagram showing connection of
RTUNE and CTUNE to tune the control loop of the
module. Note: The capacitors used in the Tunable Loop
table are 47uF/3m Ω ESR ceramic and
330uF/12mΩ ESR polymer capacitors.
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Digital Feature Description
PMBus Interface Capability
The 12A Digital Tomodachi power modules have a
PMBus interface that supports both communication
and control. The PMBus Power Management
Protocol Specification can be obtained from
www.pmbus.org. The modules support a subset of
version 1.1 of the specification (see Table 6 for a list
of the specific commands supported). Most module
parameters can be programmed using PMBus and
stored as defaults for later use.
All communication over the module PMBus interface
must support the Packet Error Checking (PEC)
scheme. The PMBus master must generate the
correct PEC byte for all transactions, and check the
PEC byte returned by the module.
The module also supports the SMBALERT response
protocol whereby the module can alert the bus
master if it wants to talk. For more information on the
SMBus alert response protocol, see the System
Management Bus (SMBus) specification.
The module has non-volatile memory that is used to
store configuration settings. Not all settings
programmed into the device are automatically saved
into this non-volatile memory, only those specifically
identified as capable of being stored can be saved
(see Table 6 for which command parameters can be
saved to non-volatile storage).
PMBus Data Format
For commands that set thresholds, voltages or report
such quantities, the module supports the “Linear”
data format among the three data formats supported
by PMBus. The Linear Data Format is a two byte
value with an 11-bit, two’s complement mantissa and
a 5-bit, two’s complement exponent. The format of
the two data bytes is shown below:
PMBus Addressing
The power module can be addressed through the
PMBus using a device address. The module has 64
possible addresses (0 to 63 in decimal) which can be
set using resistors connected from the ADDR0 and
ADDR1 pins to SIG_GND. Note that some of these
addresses (0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 12, 40,
44, 45, 55 in decimal) are reserved according to the
SMBus specifications and may not be useable. The
address is set in the form of two octal (0 to 7) digits,
with each pin setting one digit. The ADDR1 pin sets
the high order digit and ADDR0 sets the low order
digit. The resistor values suggested for each digit are
shown in Table 4 (1% tolerance resistors are
recommended). Note that if either address resistor
value is outside the range specified in Table 4, the
module will respond to address 127.
The user must know which I2C addresses are
reserved in a system for special functions and set the
address of the module to avoid interfering with other
system operations. Both 100kHz and 400kHz bus
speeds are supported by the module. Connection for
the PMBus interface should follow the High Power
DC specifications given in section 3.1.3 in the SMBus
specification V2.0 for the 400kHz bus speed or the
Low Power DC specifications in section 3.1.2. The
complete SMBus specification is available from the
SMBus web site, smbus.org.
Table 4:
Digit Resistor Value [k]
0 10
1 15.4
2 23.7
3 36.5
4 54.9
5 84.5
6 130
7 200
Data Byte High
7 6 5 4 3 2 1 07 6 5 4 3 210
Data Byte Low
Exponent
MSB Mantissa
MSB
The value is of the number is then given by
Value = Mantissa x 2Exponent
A
DDR0
SIG_GND
RADDR0 RADDR1
A
DDR1
Fig-12: Circuit showing connection of resistors
used to set the PMBus address of the module.
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PMBus Enabled On/Off
The module can also be turned on and off via the
PMBus interface. The OPERATION command is
used to actually turn the module on and off via the
PMBus, while the ON_OFF_CONFIG command
configures the combination of analog ON/OFF pin
input and PMBus commands needed to turn the
module on and off. Bit [7] in the OPERATION
command data byte enables the module, with the
following functions:
0 : Output is disabled
1 : Output is enabled
This module uses the lower five bits of the
ON_OFF_CONFIG data byte to set various ON/OFF
options as follows:
Bit Position 4 32 1 0
Access r/w r/w r/w r/w r
Function PU CMD CPR POL CPA
Default Value 1 0 1 1 1
PU: Sets the default to either operate any time input
power is present or for the ON/OFF to be controlled
by the analog ON/OFF input and the PMBus
OPERATION command. This bit is used together
with the CP, CMD and ON bits to determine startup.
Bit Value
A
ction
0
Module powers up any time power is
present regardless of state of the analog
ON/OFF pin
1
Module does not power up until
commanded by the analog ON/OFF pin
and the OPERATION command as
programmed in bits [2:0] of the
ON_OFF_CONFIG register.
CMD: The CMD bit controls how the device responds
to the OPERATION command.
Bit Value
A
ction
0 Module ignores the ON bit in the
OPERATION command
1 Module responds to the ON bit in the
OPERATION command
CPR: Sets the response of the analog ON/OFF pin.
This bit is used together with the CMD, PU and ON
bits to determine startup.
Bit Value
A
ction
0
Module ignores the analog ON/OFF pin,
i.e. ON/OFF is only controlled through the
PMBUS via the OPERATION command
1 Module requires the analog ON/OFF pin
to be asserted to start the unit
PMBus Adjustable Soft Start Rise Time
The soft start rise time can be adjusted in the module
via PMBus. When setting this parameter, make sure
that the charging current for output capacitors can be
delivered by the module in addition to any load
current to avoid nuisance tripping of the overcurrent
protection circuitry during startup. The TON_RISE
command sets the rise time in ms, and allows
choosing soft start times between 600us and 9ms,
with possible values listed in Table 5. Note that the
exponent is fixed at -4 (decimal) and the upper two
bits of the mantissa are also fixed at 0.
Table 5
Rise Time Exponent Mantissa
600us 11100 00000001010
900us 11100 00000001110
1.2ms 11100 00000010011
1.8ms 11100 00000011101
2.7ms 11100 00000101011
4.2ms 11100 00001000011
6.0ms 11100 00001100000
9.0ms 11100 00010010000
Output Voltage Adjustment Using the
PMBus
The VOUT_SCALE_LOOP parameter is important for
a number of PMBus commands related to output
voltage trimming, margining, over/under voltage
protection and the PGOOD thresholds. The output
voltage of the module is set as the combination of the
voltage divider formed by RTrim and a 20k upper
divider resistor inside the module, and the internal
reference voltage of the module. The reference
voltage VREF is nominally set at 600mV, and the
output regulation voltage is then given by
Hence the module output voltage is dependent on the
value of RTrim which is connected external to the
module. The information on the output voltage divider
ratio is conveyed to the module through the
VOUT_SCALE_LOOP parameter which is calculated
as follows:
The VOUT_SCALE_LOOP parameter is specified
using the “Linear” format and two bytes. The upper
five bits [7:3] of the high byte are used to set the
exponent which is fixed at –9 (decimal). The
remaining three bits of the high byte [2:0] and the
eight bits of the lower byte are used for the mantissa.
RTrim
RTrim
LOOPSCALEVOUT
20000
__
REFOUT V
RTrim
RTrim
V
20000
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The default value of the mantissa is 00100000000
corresponding to 256 (decimal), corresponding to a
divider ratio of 0.5. The maximum value of the
mantissa is 512 corresponding to a divider ratio of 1.
Note that the resolution of the VOUT_SCALE_LOOP
command is 0.2%.
When PMBus commands are used to trim or margin
the output voltage, the value of VREF is what is
changed inside the module, which in turn changes
the regulated output voltage of the module.
The nominal output voltage of the module can be
adjusted with a minimum step size of 0.4% over a
±25% range from nominal using the VOUT_TRIM
command over the PMBus.
The VOUT_TRIM command is used to apply a fixed
offset voltage to the output voltage command value
using the “Linear” mode with the exponent fixed at
–10 (decimal). The value of the offset voltage is given
by
This offset voltage is added to the voltage set through
the divider ratio and nominal VREF to produce the
trimmed output voltage. The valid range in two’s
complement for this command is –4000h to 3999h.
The high order two bits of the high byte must both be
either 0 or 1. If a value outside of the +/-25%
adjustment range is given with this command, the
module will set it’s output voltage to the nominal
value (as if VOUT_TRIM had been set to 0), assert
SMBALRT#, set the CML bit in STATUS_BYTE and
the invalid data bit in STATUS_CML.
Output Voltage Margining Using the PMBus
The module can also have its output voltage
margined via PMBus commands. The command
VOUT_MARGIN_HIGH sets the margin high voltage,
while the command VOUT_MARGIN_LOW sets the
margin low voltage. Both the VOUT_MARGIN_HIGH
and VOUT_MARGIN_LOW commands use the
“Linear” mode with the exponent fixed at –10
(decimal). Two bytes are used for the mantissa with
the upper bit [7] of the high byte fixed at 0. The actual
margined output voltage is a combination of the
VOUT_MARGIN_HIGH or VOUT_MARGIN_LOW
and the VOUT_TRIM values as shown below.
Note that the sum of the margin and trim voltages
cannot be outside the ±25% window around the
nominal output voltage. The data associated with
VOUT_MARGIN_HIGH and VOUT_MARGIN_LOW
can be stored to non-volatile memory using the
STORE_DEFAULT_ALL command.
The module is commanded to go to the margined
high or low voltages using the OPERATION
command. Bits [5:2] are used to enable margining as
follows:
00XX : Margin Off
0101 : Margin Low (Ignore Fault)
0110 : Margin Low (Act on Fault)
1001 : Margin High (Ignore Fault)
1010 : Margin High (Act on Fault)
PMBus Adjustable Overcurrent Warning
The module can provide an overcurrent warning via
the PMBus. The threshold for the overcurrent
warning can be set using the parameter
IOUT_OC_WARN_LIMIT. This command uses the
“Linear” data format with a two byte data word where
the upper five bits [7:3] of the high byte represent the
exponent and the remaining three bits of the high
byte [2:0] and the eight bits in the low byte represent
the mantissa. The exponent is fixed at –1 (decimal).
The upper five bits of the mantissa are fixed at 0
while the lower six bits are programmable. For
production codes after April 2013, the value for
IOUT_OC_WARN_LIMIT will be fixed at 14.5A. For
earlier production codes the actual value for
IOUT_OC_WARN_LIMIT will vary from module to
module due to calibration during production testing.
The resolution of this warning limit is 500mA. The
value of the IOUT_OC_WARN_LIMIT can be stored
to non-volatile memory using the
STORE_DEFAULT_ALL command.
Temperature Status via PMBus
The module can provide information related to
temperature of the module through the
STATUS_TEMPERATURE command. The command
returns information about whether the pre-set over
temperature fault threshold and/or the warning
threshold have been exceeded.
PMBus Adjustable Output Over and Under
Voltage Protection
The module has output over and under voltage
protection capability. The PMBus command
VOUT_OV_FAULT_LIMIT is used to set the output
over voltage threshold from four possible values:
108%, 110%, 112% or 115% of the commanded
output voltage. The command
10
)( 2_
TRIMVOUTV offsetOUT
10
)(
2)___(
TRIMVOUTHIGHMARGINVOUT
VMHOUT
10
)(
2)___(
TRIMVOUTLOWMARGINVOUT
VMLOUT
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VOUT_UV_FAULT_LIMIT sets the threshold that
causes an output under voltage fault and can also be
selected from four possible values: 92%, 90%, 88%
or 85%. The default values are 112% and 88% of
commanded output voltage. Both commands use two
data bytes formatted as two’s complement binary
integers. The “Linear” mode is used with the
exponent fixed to –10 (decimal) and the effective
over or under voltage trip points given by:
Values within the supported range for over and
undervoltage detection thresholds will be set to the
nearest fixed percentage. Note that the correct value
for VOUT_SCALE_LOOP must be set in the module
for the correct over or under voltage trip points to be
calculated.
In addition to adjustable output voltage protection, the
12A Digital Tomodachi module can also be
programmed for the response to the fault. The
VOUT_OV_FAULT_RESPONSE and
VOUT_UV_FAULT_RESPONSE commands specify
the response to the fault. Both these commands use
a single data byte with the possible options as shown
below.
1. Continue operation without interruption
(Bits [7:6] = 00, Bits [5:3] = xxx)
2. Continue for four switching cycles and then shut
down if the fault is still present, followed by no
restart or continuous restart
(Bits [7:6] = 01, Bits [5:3] = 000 means no restart,
Bits [5:3] = 111 means continuous restart)
3. Immediate shut down followed by no restart or
continuous restart
(Bits [7:6] = 10, Bits [5:3] = 000 means no restart,
Bits [5:3] = 111 means continuous restart).
4. Module output is disabled when the fault is
present and the output is enabled when the fault
no longer exists
(Bits [7:6] = 11, Bits [5:3] = xxx).
Note that separate response choices are possible for
output over voltage or under voltage faults.
PMBus Adjustable Input Undervoltage
Lockout
The module allows adjustment of the input under
voltage lockout and hysteresis. The command
VIN_ON allows setting the input voltage turn on
threshold, while the VIN_OFF command sets the
input voltage turn off threshold. For the VIN_ON
command, possible values are 2.75V, and 3V to 14V
in 0.5V steps. For the VIN_OFF command, possible
values are 2.5V to 14V in 0.5V steps. If other values
are entered for either command, they will be mapped
to the closest of the allowed values.
VIN_ON must be set higher than VIN_OFF.
Attempting to write either VIN_ON lower than
VIN_OFF or VIN_OFF higher than VIN_ON results in
the new value being rejected, SMBALERT being
asserted along with the CML bit in STATUS_BYTE
and the invalid data bit in STATUS_CML.
Both the VIN_ON and VIN_OFF commands use the
“Linear” format with two data bytes. The upper five
bits represent the exponent (fixed at -2) and the
remaining 11 bits represent the mantissa. For the
mantissa, the four most significant bits are fixed at 0.
Power Good
The module provides a Power Good (PGOOD) signal
that is implemented with an open-drain output to
indicate that the output voltage is within the
regulation limits of the power module. The PGOOD
signal will be de-asserted to a low state if any
condition such as overtemperature, overcurrent or
loss of regulation occurs that would result in the
output voltage going outside the specified thresholds.
The PGOOD thresholds are user selectable via the
PMBus (the default values are as shown in the
Feature Specifications Section). Each threshold is
set up symmetrically above and below the nominal
value. The POWER_GOOD_ON command sets the
output voltage level above which PGOOD is asserted
(lower threshold). For example, with a 1.2V nominal
output voltage, the POWER_GOOD_ON threshold
can set the lower threshold to 1.14 or 1.1V. Doing
this will automatically set the upper thresholds to 1.26
or 1.3V.
The POWER_GOOD_OFF command sets the level
below which the PGOOD command is de-asserted.
This command also sets two thresholds
symmetrically placed around the nominal output
voltage. Normally, the POWER_GOOD_ON
threshold is set higher than the
POWER_GOOD_OFF threshold.
Both POWER_GOOD_ON and
POWER_GOOD_OFF commands use the “Linear”
format with the exponent fixed at –10 (decimal).
The two thresholds are given by
Both commands use two data bytes with bit [7] of the
high byte fixed at 0, while the remaining bits are r/w
and used to set the mantissa using two’s complement
representation. Both commands also use the
VOUT_SCALE_LOOP parameter so it must be set
correctly. The default value of POWER_GOOD_ON
10
)_(
10
)_(
2)___(
2)___(
LIMITFAULTUVVOUTV
LIMITFAULTOVVOUTV
REQUVOUT
REQOVOUT
10
)_(
10
)_(
2)__(
2)__(
OFFGOODPOWERV
ONGOODPOWERV
OFFPGOODOUT
ONPGOODOUT
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is set at 1.1035V and that of the
POWER_GOOD_OFF is set at 1.08V. The values
associated with these commands can be stored in
non-volatile memory using the
STORE_DEFAULT_ALL command.
The PGOOD terminal can be connected through a
pullup resistor (suggested value 100K) to a source
of 5VDC or lower.
Measurement of Output Current, Output
Voltage and Input Voltage
The module is capable of measuring key module
parameters such as output current and voltage and
input voltage and providing this information through
the PMBus interface. Roughly every 200us, the
module makes 16 measurements each of output
current, voltage and input voltage. Average values of
of these 16 measurements are then calculated and
placed in the appropriate registers. The values in the
registers can then be read using the PMBus
interface.
Measuring Output Current Using the PMBus
The module measures current by using the inductor
winding resistance as a current sense element. The
inductor winding resistance is then the current gain
factor used to scale the measured voltage into a
current reading. This gain factor is the argument of
the IOUT_CAL_GAIN command, and consists of two
bytes in the linear data format. The exponent uses
the upper five bits [7:3] of the high data byte in two-s
complement format and is fixed at –15 (decimal). The
remaining 11 bits in two’s complement binary format
represent the mantissa.
The current measurement accuracy is also improved
by each module being calibrated during manufacture
with the offset in the current reading. The
IOUT_CAL_OFFSET command is used to store and
read the current offset. The argument for this
command consists of two bytes composed of a 5-bit
exponent (fixed at -4d) and a 11-bit mantissa. This
command has a resolution of 62.5mA and a range of
-4000mA to +3937.5mA. During manufacture, each
module is calibrated by measuring and storing the
current gain factor and offset into non-volatile
storage.
The READ_IOUT command provides module
average output current information. This command
only supports positive or current sourced from the
module. If the converter is sinking current a reading
of 0 is provided. The READ_IOUT command returns
two bytes of data in the linear data format. The
exponent uses the upper five bits [7:3] of the high
data byte in two-s complement format and is fixed at
–4 (decimal). The remaining 11 bits in two’s
complement binary format represent the mantissa
with the 11th bit fixed at 0 since only positive numbers
are considered valid.
Note that the current reading provided by the module
is not corrected for temperature. The temperature
corrected current reading for module temperature
TModule can be estimated using the following equation.
where IOUT_CORR is the temperature corrected value of
the current measurement, IREAD_OUT is the module
current measurement value, TIND is the temperature
of the inductor winding on the module. Since it may
be difficult to measure TIND, it may be approximated
by an estimate of the module temperature.
Measuring Output Voltage Using the PMBus
The module can provide output voltage information
using the READ_VOUT command. The command
returns two bytes of data all representing the
mantissa while the exponent is fixed at -10 (decimal).
During manufacture of the module, offset and gain
correction values are written into the non-volatile
memory of the module. The command
VOUT_CAL_OFFSET can be used to read and/or
write the offset (two bytes consisting of a 16-bit
mantissa in two’s complement format) while the
exponent is always fixed at -10 (decimal). The
allowed range for this offset correction is -125 to
124mV. The command VOUT_CAL_GAIN can be
used to read and/or write the gain correction - two
bytes consisting of a five-bit exponent (fixed at -8)
and a 11-bit mantissa. The range of this correction
factor is -0.125V to +0.121V, with a resolution of
0.004V. The corrected output voltage reading is then
given by:
Measuring Input Voltage Using the PMBus
The module can provide output voltage information
using the READ_VIN command. The command
returns two bytes of data in the linear format. The
upper five bits [7:3] of the high data form the two’s
complement representation of the mantissa which is
fixed at –5 (decimal). The remaining 11 bits are used
for two’s complement representation of the mantissa,
OFFSETCALVOUT GAINCALVOUTInitialV FinalV
OUT
OUT
__
)]__1()([
)(
]00393.0)30[(1
_
,
IND
OUTREAD
CORROUT TI
I
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with the 11th bit fixed at zero since only positive
numbers are valid.
During module manufacture, offset and gain
correction values are written into the non-volatile
memory of the module. The command
VIN_CAL_OFFSET can be used to read and/or write
the offset - two bytes consisting of a five-bit exponent
(fixed at -5) and a 11-bit mantissa in two’s
complement format. The allowed range for this offset
correction is -2 to 1.968V, and the resolution is
32mV. The command VIN_CAL_GAIN can be used
to read and/or write the gain correction - two bytes
consisting of a five-bit exponent (fixed at -8) and a
11-bit mantissa. The range of this correction factor is
-0.125V to +0.121V, with a resolution of 0.004V. The
corrected output voltage reading is then given by:
Reading the Status of the Module using the
PMBus
The module supports a number of status information
commands implemented in PMBus. However, not all
features are supported in these commands. A 1 in
the bit position indicates the fault that is flagged.
STATUS_BYTE: Returns one byte of information
with a summary of the most critical device faults.
Bit
Position Flag Default
Value
7 X 0
6 OFF 0
5 VOUT Overvoltage 0
4 IOUT Overcurrent 0
3 VIN Undervoltage 0
2 Temperature 0
1 CML (Comm. Memory Fault) 0
0 None of the above 0
STATUS_WORD: Returns two bytes of information
with a summary of the module’s fault/warning
conditions. Low Byte
Bit
Position Flag Default
Value
7 X 0
6 OFF 0
5 VOUT Overvoltage 0
4 IOUT Overcurrent 0
3 VIN Undervoltage 0
2 Temperature 0
1 CML (Comm. Memory Fault) 0
0 None of the above 0
High Byte
Bit
Position Flag Default
Value
7 VOUT fault or warning 0
6 IOUT fault or warning 0
5 X 0
4 X 0
3 POWER_GOOD# (is negated) 0
2 X 0
1 X 0
0 X 0
STATUS_VOUT: Returns one byte of information
relating to the status of the module’s output voltage
related faults.
STATUS_IOUT: Returns one byte of information
relating to the status of the module’s output voltage
related faults.
Bit
Position Flag Default
Value
7 IOUT OC Fault 0
6 X 0
5 IOUT OC Warning 0
4 X 0
3 X 0
2 X 0
1 X 0
0 X 0
STATUS_TEMPERATURE: Returns one byte of
information relating to the status of the module’s
temperature related faults.
Bit
Position Flag Default
Value
7 OT Fault 0
6 OT Warning 0
5 X 0
4 X 0
3 X 0
2 X 0
1 X 0
0 X 0
Bit
Position Flag Default
Value
7 VOUT OV Fault 0
6 X 0
5 X 0
4 VOUT UV Fault 0
3 X 0
2 X 0
1 X 0
0 X 0
OFFSETCALVIN GAINCALVINInitialV FinalV
IN
IN
__
)]__1()([
)(
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STATUS_CML: Returns one byte of information
relating to the status of the module’s communication
related faults.
Bit
Position Flag Default
Value
7 Invalid/Unsupported
Command 0
6 Invalid/Unsupported
Command 0
5 Packet Error Check Failed 0
4 X 0
3 X 0
2 X 0
1 Other Communication Fault 0
0 X 0
MFR_VIN_MIN: Returns minimum input voltage as
two data bytes of information in Linear format (upper
five bits are exponent – fixed at -2, and lower 11 bits
are mantissa in two’s complement format – fixed at
12)
MFR_VOUT_MIN: Returns minimum output voltage
as two data bytes of information in Linear format
(upper five bits are exponent – fixed at -10, and lower
11 bits are mantissa in two’s complement format –
fixed at 614)
MFR_SPECIFIC_00: Returns information related to
the type of module. Bits [7:2] in the Low Byte indicate
the module type (000000 corresponds to the
FGSD12SR6012 module) Bits [1:0] in the High Byte
are used to indicate the manufacturer ID, with 01
reserved for FDK.
Low Byte
Bit
Position Flag Default
Value
7:2 Module Name 000000
1:0 Reserved 10
High Byte
Bit
Position Flag Default
Value
7:2 Module Revision Number None
1:0 Manufacturer ID 01