MIC59300
Ultra High Speed 3A LDO
General Description
The MIC59300 is a high-bandwidth, low-dropout, 3A linear
voltage regulator ideal for powering core voltages of low-
power microprocessors. The MIC59300 implements a dual
supply configuration allowing for a very low output
impedance and a very fast transient response.
The MIC59300 requires a bias input supply and a main
input supply, allowing for ultra-low input voltages on the
main supply rail. The device operates from an input supply
of 1.0V to 3.8V and bias supply between 3V and 5.5V. The
MIC59300 offers fixed output voltages and adjustable
output voltages down to 0.5V.
The MIC59300 requires a minimum output capacitance for
stability, working optimally with small ceramic capacitors.
The MIC59300 is available in a 5-pin TO-263 and an 8-pin
EPAD SOIC package and its junction temperature range is
–40°C to +125°C.
Data sheets and support documentation can be found on
Micrel’s web site at: www.micrel.com.
Features
• Input voltage range:
– VIN = 1.0V to 3.8V
– VBIAS = 3.0V to 5.5V
• Stable with 1µF ceramic capacitor
• ±1% initial tolerance
• Maximum dropout voltage of 500mV over temperature
• Adjustable output voltage down to 0.5V
• Ultra fast transient response
• Excellent line and load regulation specifications
• Logic controlled shutdown option
• Thermal shutdown and current limit protection
• Junction temperature range: –40°C to +125°C
• TO-263 & 8-pin EPAD SOIC
• Pin Compatible Upgrade to MIC49300
Applications
• Telecommunications processors
• Graphics processors
• Computer peripheral cards
• Logic IC power supply
• SMPS post regulators
• Microprocessors
• Digital TV’s
_________________________________________________________________________________________________________
Typical Application
VIN
VBIAS
VOUT
ADJ
EN
GND EP
VIN
V
BIAS
EN
CIN=1µF
(Ceramic)
CBIAS=1µF
(Ceramic)
COUT=1µF
(Ceramic)
R1
R2
VOUT
MIC59300YME
1
2
3, 6
89
7
4, 5
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
January 2009 M9999-010809-A
Micrel, Inc. MIC59300
January 2009 2 M9999-010809-A
Ordering Information
Part Number Voltage(1) Junction Temperature Range Package Lead Finish
MIC59300-1.2YME 1.2V –40°C to +125°C 8-Pin EPAD SOIC RoHS Compliant
MIC59300YME Adj. –40°C to +125°C 8-Pin EPAD SOIC RoHS Compliant
MIC59300-1.2WU 1.2V –40°C to +125°C 5-Pin TO-263 RoHS Compliant
MIC59300WU Adj. –40°C to +125°C 5-Pin TO-263 RoHS Compliant
Note:
1. Other Voltage available. Contact Micrel for detail.
Pin Configur ation
8-Pin EPAD SOIC
MIC59300YME 8-Pin EPAD SOIC
MIC59300-1.2YME
VOUT
VIN
GND
ADJ
VBIAS
VOUT
VIN
GND
EN
VBIAS
5-Pin TO-263
MIC59300WU 5-Pin TO-263
MIC59300-1.2WU
Micrel, Inc. MIC59300
January 2009 3 M9999-010809-A
Pin Description
Pin Number
SOIC-8
Pin Number
TO-263
Pin Name Pin Function
1 1 (fixed) EN
Enable (Input): CMOS compatible input. Logic high = enable, logic low
= shutdown.
2 2 VBIAS
Input bias voltage for powering all circuitry on the regulator with the
exception of the output power device.
3, 6 4 VIN Input voltage needed for the output power device.
4, 5 5 VOUT Regulator Output.
7 (adjustable) 1 (adjustable) ADJ Adjustable regulator feedback input. Connect to resistor voltage divider.
7 (fixed) SENSE Connect to VOUT for fixed voltage options.
8 3 GND Ground.
9 6 EP Exposed Pad: Connect to ground pin.
Micrel, Inc. MIC59300
January 2009 4 M9999-010809-A
Absolute Maximum Ratings(1)
Supply Voltage (VIN)........................................ –0.3V to +4V
Bias Supply Voltage (VBIAS)............................. –0.3V to +6V
Enable Input Voltage (VEN)............................. –0.3V to VBIAS
Power Dissipation .....................................Internally Limited
Storage Temperature (Ts) .........................–65°C to +150°C
ESD Rating(3).................................................................. 3kV
Operating Ratings(2)
Supply Voltage (VIN)............................................ 1V to 3.8V
Bias Supply Voltage (VBIAS)................................. 3V to 5.5V
Enable Input Voltage (VEN).................................. 0V to VBIAS
Junction Temperature (TJ) ..................–40°C ≤ TJ ≤ +125°C
Package Thermal Resistance
EPAD SOIC (θJA) ...............................................41°C/W
TO-263 (θJC)………………………………… ......6.3°C/W
Electrical Characteristics(4)
TA = 25°C with VBIAS = VOUT + 2.2V; VIN = VOUT + 1V; ILOAD = 10mA; bold values indicate 0°C ≤ TJ ≤ 85°C, unless otherwise
specified.
Parameter Condition Min Typ Max Units
Room temperature 1 1 % Output Voltage Accuracy
(Fixed Voltage Options) Over temperature range 2 2
%
Line Regulation (VIN) VIN = VOUT + 1V to 3.8V 0.0015 0.1 %/V
Line Regulation (VBIAS) VBIAS = 3V to 5.5V (VOUT < 0.8V)
VBIAS = VOUT + 2.2V to 5.5V (VOUT ≥ 0.8V)
0.035
0.3 %/V
Room temperature 0.495 0.5 0.505 V
Feedback Voltage
(Adjustable Output Voltage) Over temperature range 0.490 0.5 0.510 V
IL = 10mA to 3A (SOIC) 0.15 0.5 % Output Voltage Load Regulation
IL = 10mA to 3A (TO-263) 0.15 0.5 %
IL = 1.5A 93 250 mV
IL = 3A (SOIC) 205 400 mV
VIN – VOUT; Dropout Voltage
IL = 3A (TO-263) 205 500 mV
VBIAS – VOUT; Dropout Voltage IL = 3A 0.91 2.1 V
VBIAS supply current VEN = 2V, IL = 100mA
VEN = 2V, IL = 3A
2
30
7.5
150 mA
mA
VBIAS shutdown current VEN = 0V 0.1 1 µA
VIN shutdown current VEN = 0V 0.1 1 µA
FB bias current Adj only 0.02 1 µA
VBIAS rising 2.7 2.85 3.0 V UVLO
Hysteresis 100 mV
Current Limit VOUT = 0V 3.3 4.7 9.0 A
Enable Input
Enable Input Threshold Regulator enable
Regulator shutdown
1.6 0.85
0.75
0.3 V
V
Enable Pin Input Current Independent of state 0.002 1 µA
AC Response
Large signal bandwidth 1 MHz
PSRR (BIAS) at 10kHz VBIAS = 3.3V, IOUT = 1.5A 45 dB
PSRR (IN) at 10kHz VIN = VOUT + 1V, IOUT = 1.5A
VIN = VOUT + 0.3V, IOUT = 1.5A
65
55
dB
dB
Thermal Shutdown 145 °C
Micrel, Inc. MIC59300
January 2009 5 M9999-010809-A
Thermal Shutdown Hysteresis 10 °C
Turn-on Time 90 300 µs
Notes:
1. Exceeding the absolute maximum rating may damage the device.
2. The device is not guaranteed to function outside its operating rating.
3. Devices are ESD sensitive. Handling precautions recommended. Human body model, 1.5kΩ in series with 100pF.
4. Specification for packaged product only.
Micrel, Inc. MIC59300
January 2009 6 M9999-010809-A
Typical Characteristics
0
0.01 0.1 1 10 100 1000
FREQUENCY (kHz)
10
20
30
40
50
60
70
80
90
PSRR (dB)
Power Supply
Rejection Ratio (VIN)
VBIAS = 3.3V
VIN = 1.8V
VOUT = 1V
IOUT = 1.5A
0
0.01 0.1 1 10 100 1000
FREQUENCY (kHz)
10
20
30
40
50
60
70
80
90
PSRR (dB)
Power Supply
Rejection Ratio (VBIAS)
VBIAS = 3.3V
VIN = 1.8V
VOUT = 1V
IOUT = 1.5A
0
1.5 1.8 2.1 2.4 2.7 3
OUTPUT CURRENT (A)
20
40
60
80
100
120
140
160
180
200
220
DROPOUT VOLTAGE (mV)
Dropout Voltage
(VIN)
VBIAS = 3.3V
VOUT = 1V
0
0
0.3
0.6
0.9
1.2
1.5
1.8
2.1
2.4
2.7
3
OUTPUT CURRENT (A)
0.2
0.4
0.6
0.8
1
1.2
DROPOUT VOLTAGE (V)
VIN = 3V
Dropout Voltage
(VBIAS)
VOUT = 2.5V
0
-40
-20
0
20
40
60
80
100
120
TEMPERATURE (°C)
50
100
150
200
250
300
350
DROPOUT VOLTAGE (mV)
Dropout Voltage vs.
Temperature (VIN)
VBIAS = 5.5V
VOUT = 3.45V
IOUT = 3A
0
-40
-20
0
20
40
60
80
100
120
TEMPERATURE (°C)
0.2
0.4
0.6
0.8
1
1.2
DROPOUT VOLTAGE (V)
Dropout Voltage vs.
Temperature (VBIAS)
VIN = 3.8V
VOUT = 3.45V
IOUT = 3A
0
012345
BIAS VOLTAGE (V)
0.5
1
1.5
2
2.5
3
OUTPUT VOLTAGE (V)
Dropout Characteristics
(VBIAS)
10mA
3A
VIN = 3V
VOUT = 2.5V
0.995
0.996
0
0.3
0.6
0.9
1.2
1.5
1.8
2.1
2.4
2.7
3
OUTPUT CURRENT (A)
0.997
0.998
0.999
1.000
1.001
1.002
1.003
1.004
1.005
1.006
1.007
1.008
1.009
1.010
OUTPUT VOLTAGE (V)
Load Regulation
VBIAS = 3.3V
VIN = 1.5V
VOUT = 1V
0
-40
-20
0
20
40
60
80
100
120
TEMPERATURE (°C)
10
20
30
40
50
60
70
BIAS CURRENT (mA)
Bias Current
vs. Temperature
IOUT=100mA
IOUT=3.0A
IOUT=1.5A
VBIAS = 3V
VIN = 1.5V
VOUT = 0.5V
Bias Current
vs. Output Current
0
5
10
15
20
25
30
35
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
2.2
2.4
2.6
2.8
3
BIAS CURRENT (mA)
OUTPUT CURRENT (A)
VBIAS = 3V
VIN = 1.5V
VOUT = 0.5V
0.9
1
1.1
1.2
1.3
1.4
1.5
3 3.5 4 4.5 5 5.5
GROUND CURRENT (mA)
BIAS VOLTAGE (V)
Ground Current
vs. Bias Voltage
0.496
0.497
0.498
0.499
0.500
0.501
0.502
0.503
0.504
1.5 1.9 2.3 2.7 3.1 3.5 3.9
FEEDBACK VOLTAGE (V)
INPUT VOLTAGE (V)
Feedback Voltage
vs. Input Voltage
VBIAS = 3.3V
VOUT = 1V
VIN = 1.8V
VOUT = 1V
Micrel, Inc. MIC59300
January 2009 7 M9999-010809-A
Typical Characteristics (continued)
0.495
33.544.555.5
BIAS VOLTAGE (V)
0.496
0.497
0.498
0.499
0.500
0.501
0.502
0.503
0.504
0.505
FEEDBACK VOLTAGE (V)
Feedback Voltage
vs. Bias Voltage
VIN = 1.5V
VOUT = 1V
0.49
0.492
0.494
0.496
0.498
0.5
0.502
0.504
0.506
0.508
0.51
-40
-20
0
20
40
60
80
100
120
FEEDBACK VOLTAGE (V)
TEMPERATURE (°C)
Feedback Voltage
vs. Temperature
0
33.544.555.5
BIAS VOLTAGE (V)
0.2
0.4
0.6
0.8
1
1.2
ENABLE THRESHOLD (V)
Enable Threshold
vs. Bias Voltage
VIN = 1.8V
VBIAS = 3.3V
VIN = 1.5V VOUT = 1V
Micrel, Inc. MIC59300
Functional Characteristics
January 2009 8 M9999-010809-A
Micrel, Inc. MIC59300
January 2009 9 M9999-010809-A
Functional Diagram
VOUT
Enable Bandgap
VBIAS
VIN
Ilimit
EN
A
DJ
MIC59300 (Adj) Block Diag ram
VOUT
Enable Bandgap
VBIAS
VIN
Ilimit
EN
SENSE R1
R2
MIC59300 (Fixed) Block Diagram
Micrel, Inc. MIC59300
January 2009 10 M9999-010809-A
Application Information
The MIC59300 is an ultra-high performance, low-dropout
linear regulator designed for high current applications
requiring a fast transient response. The MIC59300
utilizes two input supplies, significantly reducing dropout
voltage, making it perfect for low-voltage, DC-to-DC
conversion. The MIC59300 requires a minimum number
of external components, and as a μCap regulator, the
output is tolerant of virtually any type of capacitor,
including ceramic type and tantalum type capacitors.
The MIC59300 regulator is fully protected from damage
due to fault conditions, offering linear current limiting and
thermal shutdown.
Bias Supply Voltage
VBIAS, requiring relatively light current, provides power to
the control portion of the MIC59300. VBIAS requires
approximately 30mA for a 3A load current. Dropout
conditions require higher currents. Most of the biasing
current is used to supply the base current to the pass
transistor. The bias voltage allows the pass element to
be driven into saturation, reducing the dropout to 205mV
at a 3A load current. Bypassing on the bias pin is
recommended to improve performance of the regulator
during line and load transients. Small ceramic capacitors
from VBIAS-to-ground help reduce high frequency noise
from being injected into the control circuitry from the bias
rail and constitute good design practice. Good bypass
techniques typically include one larger capacitor such as
1μF ceramic and smaller valued capacitors such as
0.01μF or 0.001μF in parallel with that larger capacitor to
decouple the bias supply. The VBIAS input voltage must
be 2.1V above the output voltage with a minimum VBIAS
input voltage of 3V.
Input Supply Voltage
VIN provides the high current to the collector of the pass
transistor. The minimum input voltage is 1.0V, allowing
conversion from low voltage supplies.
Output Capacitor
The MIC59300 requires a minimum of output
capacitance to maintain stability. However, proper
capacitor selection is important to ensure desired
transient response. The MIC59300 is specifically
designed to be stable with virtually any capacitance
value and ESR. A 1μF ceramic chip capacitor should
satisfy most applications. Output capacitance can be
increased without bound. See the “Functional
Characteristics” for examples of load transient response.
X7R dielectric ceramic capacitors are recommended
because of their temperature performance. X7R-type
capacitors change capacitance by 15% over their
operating temperature range and are the most stable
type of ceramic capacitors. Z5U and Y5V dielectric
capacitors change value by as much as 50% and 60%
respectively over their operating temperature ranges. To
use a ceramic chip capacitor with Y5V dielectric, the
value must be much higher than an X7R ceramic or a
tantalum capacitor to ensure the same capacitance
value over the operating temperature range. Tantalum
capacitors have a very stable dielectric (10% over their
operating temperature range) and can also be used with
this device.
Input Capacitor
An input capacitor of 1μF or greater is recommended
when the device is more than 4 inches away from the
bulk supply capacitance, or when the supply is a battery.
Small, surface-mount, ceramic chip capacitors can be
used for the bypassing. The capacitor should be placed
within 1 inch of the device for optimal performance.
Larger values will help to improve ripple rejection by
bypassing the input to the regulator, further improving
the integrity of the output voltage.
Thermal Design
Linear regulators are simple to use. The most
complicated design parameters to consider are thermal
characteristics. Thermal design requires the following
application-specific parameters:
• Maximum ambient temperature (TA)
• Output current (IOUT)
• Output voltage (VOUT)
• Input voltage (VIN)
• Ground current (IGND)
First, calculate the power dissipation (PD) of the
regulator from these numbers and the device
parameters from this datasheet.
OUTOUTBIASBIASININD IVIVIVP
×
−×
+
×
=
The input current will be less than the output current at
high output currents as the load increases. The bias
current is a sum of base drive and ground current.
Ground current is constant over load current. Then the
heat sink thermal resistance is determined with this
formula:
()
CSJC
D
AMAXJ
SA PTT
θθθ
+−
⎟
⎟
⎠
⎞
⎜
⎜
⎝
⎛−
=)(
The heat sink may be significantly reduced in
applications where the maximum input voltage is known
and large compared with the dropout voltage. Use a
series input resistor to drop excessive voltage and
distribute the heat between this resistor and the
regulator. The low-dropout properties of the MIC59300
allow significant reductions in regulator power dissipation
and the associated heat sink without compromising
performance. When this technique is employed, a
Micrel, Inc. MIC59300
January 2009 11 M9999-010809-A
capacitor of at least 1μF is needed directly between the
input and regulator ground. Refer to “Application Note 9 ”
(http://www.micrel.com/_PDF/App-Notes/an-9.pdf) for
further details and examples on thermal design and heat
sink specification.
⎟
⎠
⎞
⎜
⎝
⎛−×= 1
5.0
V
RR OUT
21
where VOUT is the desired output voltage.
Enable
Minimum Load Current An active high enable input (EN) allows on-off control of
the regulator. Current drain reduces to “zero” when the
device is shutdown, with only microamperes of leakage
current. The EN input has CMOS compatible thresholds
for simple logic interfacing. EN may be directly tied to
VBIAS and pulled up to the maximum supply voltage.
The MIC59300, unlike most other high current
regulators, does not require a minimum load to maintain
output voltage regulation.
Adjustable Regulator Design
The MIC59300 adjustable version allows programming
the output voltage anywhere between 0.5Vand 3.3V.
Two resistors are used. The resistor value between VOUT
and the adjust pin should not exceed 10kΩ. Larger
values can cause instability. The resistor values are
calculated by:
EPad
The exposed pad on the bottom of the SOIC part must
be connected to ground.
Micrel, Inc. MIC59300
January 2009 12 M9999-010809-A
J5
GND
R1
1K
13
2
JP1
C1
1uF/6.3V
C2
1uF/6.3V
C3
1uF/6.3V
C4
OPEN
VIN
3
GND
8
VOUT 4
ADJ
EP
7
EN
19
VIN
6
VBIAS
2
VOUT 5
U1
MIC59300YME
R2
1K
J2
GND
J3
VBIAS
3V to 5.5V
J1
VIN
1V to 3.8V
R3
698
R4
499
R5
383
12
34
56
78
JP2
A
Option for Fixed VOUT
R1 = 0
Remove all Jumpers from JP2
JP2 = Voltages Selector
A VOUT = 1.0V
B VOUT = 1.2V
C VOUT = 1.5V
D VOUT = 1.8V
J4
VOUT
BCD
Bill of Materials
Item Part Number Manufacturer Description Qty.
C1608X5R0J105K TDK(1)
GRM188R60J105KA01D Murata(2)
C1,C2
C3
0603D105KAT2A AVX(3)
1uF Ceramic Capacitor X5R 0603 6.3V 3
C4 Open 1
R1,R2 CRCW06031K00FKXX Vishay(4) 1kΩ 1% 0603 Resistor 2
R3 CRCW0603698RFKXX Vishay(4) 698Ω 1% 0603 Resistor 1
R4 CRCW0603499RFKXX Vishay(4) 499Ω 1% 0603 Resistor 1
R5 CRCW0603383RFKXX Vishay(4) 383Ω 1% 0603 Resistor 1
U1 MIC59300YME Micrel, Inc.(5) Ultra High Speed 3A LDO 1
Notes:
1. TDK: www.tdk.com
2. Murata Tel: www.murata.com
3. AVX Tel: www.avx.com
4. Vishay Tel: www.vishay.com
5. Micrel, Inc.: www.micrel.com
Micrel, Inc. MIC59300
January 2009 13 M9999-010809-A
PCB Layout Recommendations
Top Layer
Bottom Layer
Micrel, Inc. MIC59300
January 2009 14 M9999-010809-A
Package Information
8-Pin EPAD SOIC (ME)
Micrel, Inc. MIC59300
January 2009 15 M9999-010809-A
5-Pin TO-263 (WU)
MICREL, INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 USA
TEL +1 (408) 944-0800 FAX +1 (408) 474-1000 WEB http://www.micrel.com
The information furnished by Micrel in this data sheet is believed to be accurate and reliable. However, no responsibility is assumed by Micrel for its
use. Micrel reserves the right to change circuitry and specifications at any time without notification to the customer.
Micrel Products are not designed or authorized for use as components in life support appliances, devices or systems where malfunction of a product
reasonably be expected to result in personal injury. Life support devices or systems are devices or systems that (a) are intended for surgical impla
into the body or (b) support or sustain life, and whose failure to perform can be reasonably expected to result in a significant injury to the user. A
Purchaser’s use or sale of Micrel Products for use in life support appliances, devices or systems is a Purchaser’s own risk and Purchaser agrees to fully
indemnify Micrel for any damages resulting from such use or sale.
can nt
© 2009 Micrel, Incorporated.
