LM2717
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SNVS253D –MAY 2005–REVISED MARCH 2013
LM2717 Dual Step-Down DC/DC Converter
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1FEATURES DESCRIPTION
The LM2717 is composed of two PWM DC/DC buck
2• Fixed 3.3V Output Buck Converter with a 2.2A, (step-down) converters. The first converter is used to
0.16Ω, Internal Switch generate a fixed output voltage of 3.3V. The second
• Adjustable Buck Converter with a 3.2A, 0.16Ω,converter is used to generate an adjustable output
Internal Switch voltage. Both converters feature low RDSON (0.16Ω)
internal switches for maximum efficiency. Operating
• Operating Input Voltage Range of 4V to 20V frequency can be adjusted anywhere between
• Input Undervoltage Protection 300kHz and 600kHz allowing the use of small
• 300kHz to 600kHz Pin Adjustable Operating external components. External soft-start pins for each
Frequency enables the user to tailor the soft-start times to a
specific application. Each converter may also be shut
• Over Temperature Protection down independently with its own shutdown pin. The
• Small 24-Lead TSSOP Package LM2717 is available in a low profile 24-lead TSSOP
package ensuring a low profile overall solution.
APPLICATIONS
• TFT-LCD Displays
• Handheld Devices
• Portable Applications
• Laptop Computers
Typical Application Circuit
1Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
2All trademarks are the property of their respective owners.
PRODUCTION DATA information is current as of publication date. Copyright © 2005–2013, Texas Instruments Incorporated
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
LM2717
SNVS253D –MAY 2005–REVISED MARCH 2013
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Connection Diagram
Top View
Figure 1. 24-Lead TSSOP
See Package Number PW0024A
PIN DESCRIPTIONS
Pin Name Function
1 PGND Power ground. PGND and AGND pins must be connected together directly at the part.
2 PGND Power ground. PGND and AGND pins must be connected together directly at the part.
3 AGND Analog ground. PGND and AGND pins must be connected together directly at the part.
4 FB1 Fixed buck output voltage feedback input.
5 VC1 Fixed buck compensation network connection. Connected to the output of the voltage error amplifier.
6 VBG Bandgap connection.
7 VC2 Adjustable buck compensation network connection. Connected to the output of the voltage error
amplifier.
8 FB2 Adjustable buck output voltage feedback input.
9 AGND Analog ground. PGND and AGND pins must be connected together directly at the part.
10 AGND Analog ground. PGND and AGND pins must be connected together directly at the part.
11 PGND Power ground. PGND and AGND pins must be connected together directly at the part.
12 PGND Power ground. PGND and AGND pins must be connected together directly at the part.
13 SW2 Adjustable buck power switch input. Switch connected between VIN pins and SW2 pin.
14 VIN Analog power input. VIN pins should be connected together directly at the part.
15 VIN Analog power input. VIN pins should be connected together directly at the part.
16 CB2 Adjustable buck converter bootstrap capacitor connection.
17 SHDN2 Shutdown pin for adjustable buck converter. Active low.
18 SS2 Adjustable buck soft start pin.
19 FSLCT Switching frequency select input. Use a resistor to set the frequency anywhere between 300kHz and
600kHz.
20 SS1 Fixed buck soft start pin.
21 SHDN1 Shutdown pin for fixed buck converter. Active low.
22 CB1 Fixed buck converter bootstrap capacitor connection.
23 VIN Analog power input. VIN pins should be connected together directly at the part.
24 SW1 Fixed buck power switch input. Switch connected between VIN pins and SW1 pin.
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95% Duty
Cycle Limit
OSC
FSLCT
DC
LIMIT
SET
+
+
-
+
PWM
Comp RESET
-
+
OVP
Comp
Buck
Driver
BUCK
DRIVE
+
-
Error
Amp
BG
FB1
Bandgap
Soft
Start
Thermal
Shutdown
VBG VC1
OVP
TSH
SHDN1
SD
Buck Load
Current
Measurement
Fixed Buck Converter
CB1
SS1
SW1
VIN
PGND
95% Duty
Cycle Limit
OSC
FSLCT
DC
LIMIT
SET
+
+
-
+
PWM
Comp RESET
-
+
OVP
Comp
Buck
Driver
BUCK
DRIVE
+
-
Error
Amp
BG
FB2
Bandgap
Soft
Start
Thermal
Shutdown
VBG VC2
OVP
TSH
SHDN2
SD
Buck Load
Current
Measurement
Adjustable Buck Converter
CB2
SS2
SW2
VIN
PGND
36.5k
20.38k
LM2717
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SNVS253D –MAY 2005–REVISED MARCH 2013
Block Diagram
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
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Absolute Maximum Ratings(1)(2)
VIN −0.3V to 22V
SW1 Voltage −0.3V to 22V
SW2 Voltage −0.3V to 22V
FB1, FB2 Voltages −0.3V to 7V
CB1, CB2 Voltages −0.3V to VIN+7V (VIN=VSW)
VC1 Voltage 1.75V ≤VC1 ≤2.25V
VC2 Voltage 0.965V ≤VC2 ≤1.565V
SHDN1 Voltage −0.3V to 7.5V
SHDN2 Voltage −0.3V to 7.5V
SS1 Voltage −0.3V to 2.1V
SS2 Voltage −0.3V to 2.1V
FSLCT Voltage AGND to 5V
Maximum Junction Temperature 150°C
Power Dissipation(3) Internally Limited
Lead Temperature 300°C
Vapor Phase (60 sec.) 215°C
Infrared (15 sec.) 220°C
ESD Susceptibility(4) Human Body Model 2kV
(1) Absolute maximum ratings are limits beyond which damage to the device may occur. Operating Ratings are conditions for which the
device is intended to be functional, but device parameter specifications may not be ensured. For ensured specifications and test
conditions, see the Electrical Characteristics.
(2) If Military/Aerospace specified devices are required, please contact the Texas Instruments Sales Office/ Distributors for availability and
specifications.
(3) The maximum allowable power dissipation is a function of the maximum junction temperature, TJ(MAX), the junction-to-ambient thermal
resistance, θJA, and the ambient temperature, TA. See the Electrical Characteristics table for the thermal resistance. The maximum
allowable power dissipation at any ambient temperature is calculated using: PD(MAX) = (TJ(MAX) −TA)/θJA. Exceeding the maximum
allowable power dissipation will cause excessive die temperature, and the regulator will go into thermal shutdown.
(4) The human body model is a 100 pF capacitor discharged through a 1.5kΩresistor into each pin.
Operating Conditions
Operating Junction Temperature Range(1) −40°C to +125°C
Storage Temperature −65°C to +150°C
Supply Voltage 4V to 20V
SW1 Voltage 20V
SW2 Voltage 20V
(1) All limits specified at room temperature (standard typeface) and at temperature extremes (bold typeface). All room temperature limits are
100% tested or ensured through statistical analysis. All limits at temperature extremes are specified via correlation using standard
Statistical Quality Control (SQC) methods. All limits are used to calculate Average Outgoing Quality Level (AOQL).
Electrical Characteristics
Specifications in standard type face are for TJ= 25°C and those with boldface type apply over the full Operating
Temperature Range (TJ=−40°C to +125°C). VIN = 5V, IL= 0A, and FSW = 300kHz unless otherwise specified.
Symbol Parameter Conditions Min(1) Typ(2) Max(1) Units
IQTotal Quiescent Current (both Not Switching 2.7 6mA
switchers) Switching, switch open 6 12 mA
VSHDN = 0V 9 27 µA
VFB1 Fixed Buck Feedback Voltage 3.3 V
VFB2 Adjustable Buck Feedback 1.267 V
Voltage
(1) All limits specified at room temperature (standard typeface) and at temperature extremes (bold typeface). All room temperature limits are
100% tested or ensured through statistical analysis. All limits at temperature extremes are specified via correlation using standard
Statistical Quality Control (SQC) methods. All limits are used to calculate Average Outgoing Quality Level (AOQL).
(2) Typical numbers are at 25°C and represent the most likely norm.
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Electrical Characteristics (continued)
Specifications in standard type face are for TJ= 25°C and those with boldface type apply over the full Operating
Temperature Range (TJ=−40°C to +125°C). VIN = 5V, IL= 0A, and FSW = 300kHz unless otherwise specified.
Symbol Parameter Conditions Min(1) Typ(2) Max(1) Units
ICL1(3) Fixed Buck Switch Current VIN = 8V(4) 2.2 A
Limit
ICL2(3) Adjustable Buck Switch VIN = 8V(4) 3.2 A
Current Limit
IB1 Fixed Buck FB Pin Bias VIN = 20V 65 µA
Current(5)
IB2 Adjustable Buck FB Pin Bias VIN = 20V 65 nA
Current(5)
VIN Input Voltage Range 4 20 V
gm1 Fixed Buck Error Amp ΔI = 20µA 1340 µmho
Transconductance
gm2 Adjustable Buck Error Amp ΔI = 20µA 1360 µmho
Transconductance
AV1 Fixed Buck Error Amp Voltage 134 V/V
Gain
AV2 Adjustable Buck Error Amp 136 V/V
Voltage Gain
DMAX Maximum Duty Cycle 89 93 %
FSW Switching Frequency RF= 46.4k 200 300 400 kHz
RF= 22.6k 475 600 775 kHz
ISHDN1 Fixed Buck Shutdown Pin 0V < VSHDN1 < 7.5V −5 5 µA
Current
ISHDN2 Adjustable Buck Shutdown Pin 0V < VSHDN2 < 7.5V −5 5 µA
Current
IL1 Fixed Buck Switch Leakage VIN = 20V 0.01 5µA
Current
IL2 Adjustable Buck Switch VIN = 20V 0.01 5µA
Leakage Current
RDSON1 Fixed Buck Switch RDSON(6) 160 mΩ
RDSON2 Adjustable Buck Switch 160 mΩ
RDSON(6)
ThSHDN1 Fixed Buck SHDN Threshold Output High 1.8 1.36 V
Output Low 1.33 0.7
ThSHDN2 Adjustable Buck SHDN Output High 1.8 1.36 V
Threshold Output Low 1.33 0.7
ISS1 Fixed Buck Soft Start Pin 4915 µA
Current
ISS2 Adjustable Buck Soft Start Pin 4915 µA
Current
UVP On Threshold 43.8 V
Off Threshold 3.6 3.3
θJA Thermal Resistance(7) TSSOP, package only 115 °C/W
(3) Duty cycle affects current limit due to ramp generator.
(4) Current limit at 0% duty cycle. See TYPICAL PERFORMANCE section for Switch Current Limit vs. VIN
(5) Bias current flows into FB pin.
(6) Includes the bond wires, RDSON from VIN pin(s) to SW pin.
(7) Refer to Texas Instruments packaging website for more detailed thermal information and mounting techniques for the TSSOP package.
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4 6 8 10 12 14 16 18 20
INPUT VOLTAGE (V)
100
110
120
130
140
150
160
170
180
190
200
SWITCH RDS(ON) (m:
0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6
LOAD CURRENT (A)
0
10
20
30
40
50
60
70
80
90
100
VIN = 5V
VIN = 12V
VIN = 18V
EFFICIENCY (%)
4 6 8 10 12 14 16 18 20
INPUT VOLTAGE (V)
100
110
120
130
140
150
160
170
180
190
200
SWITCH RDS(ON) (m:
4 6 8 10 12 14 16 18 20
INPUT VOLTAGE (V)
290
295
300
305
310
315
320
RF= 46.4k
SWITCHING FREQUENCY (kHz)
4 6 8 10 12 14 16 18 20
INPUT VOLTAGE (V)
0
1
2
3
4
5
6
7
8
9
QUIESCENT CURRENT (mA)
4 6 8 10 12 14 16 18 20
INPUT VOLTAGE (V)
QUIESCENT CURRENT (PA)
0
2
4
6
8
10
12
14
16
LM2717
SNVS253D –MAY 2005–REVISED MARCH 2013
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Typical Performance Characteristics
Switching IQ
Shutdown IQvs.
vs. Input Voltage
Input Voltage (FSW = 300kHz)
Figure 2. Figure 3.
Switching Frequency
vs. Fixed Buck RDS(ON)
Input Voltage vs.
(FSW = 300kHz) Input Voltage
Figure 4. Figure 5.
Adjustable Buck RDS(ON) Fixed Buck Efficiency
vs. vs.
Input Voltage Load Current
Figure 6. Figure 7.
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4 6 8 10 12 14 16 18 20
INPUT VOLTAGE (V)
1
1.2
1.4
1.6
1.8
2
2.2
2.4
SWITCH CURRENT LIMIT (A)
8 10 12 14 16 18 20
INPUT VOLTAGE (V)
SWITCH CURRENT LIMIT (A)
2
2.2
2.4
2.6
2.8
3
3.2
3.4
0 0.5 1 1.5 2 2.5
LOAD CURRENT (A)
0
10
20
30
40
50
60
70
80
90
100
EFFICIENCY (%)
VIN = 18V
0 0.5 1 1.5 2 2.5
LOAD CURRENT (A)
0
10
20
30
40
50
60
70
80
90
100
EFFICIENCY (%)
VIN = 18V
LM2717
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SNVS253D –MAY 2005–REVISED MARCH 2013
Typical Performance Characteristics (continued)
Adjustable Buck Efficiency Adjustable Buck Efficiency
vs. vs.
Load Current Load Current
(VOUT = 15V) (VOUT = 5V)
Figure 8. Figure 9.
Adjustable Buck Switch Current Limt
Fixed Buck Switch Current Limt vs.
vs. Input Voltage
Input Voltage (VOUT = 5V)
Figure 10. Figure 11.
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:RFB1 = RFB2 xVOUT - 1.267
1.267
VOUT
VIN , D' = (1-D)
D =
LM2717
SNVS253D –MAY 2005–REVISED MARCH 2013
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BUCK OPERATION
PROTECTION (BOTH REGULATORS)
The LM2717 has dedicated protection circuitry running during normal operation to protect the IC. The Thermal
Shutdown circuitry turns off the power devices when the die temperature reaches excessive levels. The UVP
comparator protects the power devices during supply power startup and shutdown to prevent operation at
voltages less than the minimum input voltage. The OVP comparator is used to prevent the output voltage from
rising at no loads allowing full PWM operation over all load conditions. The LM2717 also features a shutdown
mode for each converter decreasing the supply current to approximately 10µA (both in shutdown mode).
CONTINUOUS CONDUCTION MODE
The LM2717 contains current-mode, PWM buck regulators. A buck regulator steps the input voltage down to a
lower output voltage. In continuous conduction mode (when the inductor current never reaches zero at steady
state), the buck regulator operates in two cycles. The power switch is connected between VIN and SW1 and
SW2.
In the first cycle of operation the transistor is closed and the diode is reverse biased. Energy is collected in the
inductor and the load current is supplied by COUT and the rising current through the inductor.
During the second cycle the transistor is open and the diode is forward biased due to the fact that the inductor
current cannot instantaneously change direction. The energy stored in the inductor is transferred to the load and
output capacitor.
The ratio of these two cycles determines the output voltage. The output voltage is defined approximately as:
(1)
where D is the duty cycle of the switch, D and D′will be required for design calculations.
DESIGN PROCEDURE
This section presents guidelines for selecting external components.
SETTING THE OUTPUT VOLTAGE (ADJUSTABLE REGULATOR)
The output voltage is set using the feedback pin and a resistor divider connected to the output as shown in
Figure 12. The feedback pin voltage is 1.26V, so the ratio of the feedback resistors sets the output voltage
according to the following equation:
(2)
INPUT CAPACITOR
A low ESR aluminum, tantalum, or ceramic capacitor is needed betwen the input pin and power ground. This
capacitor prevents large voltage transients from appearing at the input. The capacitor is selected based on the
RMS current and voltage requirements. The RMS current is given by:
(3)
The RMS current reaches its maximum (IOUT/2) when VIN equals 2VOUT. This value should be calculated for both
regulators and added to give a total RMS current rating. For an aluminum or ceramic capacitor, the voltage rating
should be at least 25% higher than the maximum input voltage. If a tantalum capacitor is used, the voltage rating
required is about twice the maximum input voltage. The tantalum capacitor should be surge current tested by the
manufacturer to prevent being shorted by the inrush current. The minimum capacitor value should be 47µF for
lower output load current applications and less dynamic (quickly changing) load conditions. For higher output
current applications or dynamic load conditions a 68µF to 100µF low ESR capacitor is recommended. It is also
recommended to put a small ceramic capacitor (0.1µF to 4.7µF) between the input pins and ground to reduce
high frequency spikes.
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INDUCTOR SELECTION
The most critical parameters for the inductor are the inductance, peak current and the DC resistance. The
inductance is related to the peak-to-peak inductor ripple current, the input and the output voltages (for 300kHz
operation):
(4)
A higher value of ripple current reduces inductance, but increases the conductance loss, core loss, and current
stress for the inductor and switch devices. It also requires a bigger output capacitor for the same output voltage
ripple requirement. A reasonable value is setting the ripple current to be 30% of the DC output current. Since the
ripple current increases with the input voltage, the maximum input voltage is always used to determine the
inductance. The DC resistance of the inductor is a key parameter for the efficiency. Lower DC resistance is
available with a bigger winding area. A good tradeoff between the efficiency and the core size is letting the
inductor copper loss equal 2% of the output power.
OUTPUT CAPACITOR
The selection of COUT is driven by the maximum allowable output voltage ripple. The output ripple in the constant
frequency, PWM mode is approximated by:
(5)
The ESR term usually plays the dominant role in determining the voltage ripple. Low ESR ceramic, aluminum
electrolytic, or tantalum capacitors (such as Taiyo Yuden MLCC, Nichicon PL series, Sanyo OS-CON, Sprague
593D, 594D, AVX TPS, and CDE polymer aluminum) is recommended. An electrolytic capacitor is not
recommended for temperatures below −25°C since its ESR rises dramatically at cold temperature. Ceramic or
tantalum capacitors have much better ESR specifications at cold temperature and is preferred for low
temperature applications.
BOOTSTRAP CAPACITOR
A 4.7nF ceramic capacitor or larger is recommended for the bootstrap capacitor. For applications where the input
voltage is less than twice the output voltage a larger capacitor is recommended, generally 0.1µF to 1µF to
ensure plenty of gate drive for the internal switches and a consistently low RDS(ON).
SOFT-START CAPACITOR (BOTH REGULATORS)
The LM2717 does not contain internal soft-start which allows for fast startup time but also causes high inrush
current. Therefore for applications that need reduced inrush current the LM2717 has circuitry that is used to limit
the inrush current on start-up of the DC/DC switching regulators. This inrush current limiting circuitry serves as a
soft-start. The external SS pins are used to tailor the soft-start for a specific application. A current (ISS) charges
the external soft-start capacitor, CSS. The soft-start time can be estimated as:
TSS = CSS*0.6V/ISS (6)
When programming the softstart time simply use the equation given in the Soft-Start Capacitor section above.
SHUTDOWN OPERATION (BOTH REGULATORS)
The shutdown pins of the LM2717 are designed so that they may be controlled using 1.8V or higher logic signals.
If the shutdown function is not to be used the pin may be left open. The maximum voltage to the shutdown pin
should not exceed 7.5V. If the use of a higher voltage is desired due to system or other constraints it may be
used, however a 100k or larger resistor is recommended between the applied voltage and the shutdown pin to
protect the device.
SCHOTTKY DIODE
The breakdown voltage rating of D1and D2is preferred to be 25% higher than the maximum input voltage. The
current rating for the diode should be equal to the maximum output current for best reliability in most
applications. In cases where the input voltage is much greater than the output voltage the average diode current
is lower. In this case it is possible to use a diode with a lower average current rating, approximately (1-D)*IOUT
however the peak current rating should be higher than the maximum load current.
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LAYOUT CONSIDERATIONS
The LM2717 uses two separate ground connections, PGND for the drivers and boost NMOS power device and
AGND for the sensitive analog control circuitry. The AGND and PGND pins should be tied directly together at the
package. The feedback and compensation networks should be connected directly to a dedicated analog ground
plane and this ground plane must connect to the AGND pin. If no analog ground plane is available then the
ground connections of the feedback and compensation networks must tie directly to the AGND pin. Connecting
these networks to the PGND can inject noise into the system and effect performance.
The input bypass capacitor CIN, as shown in Figure 12, must be placed close to the IC. This will reduce copper
trace resistance which effects input voltage ripple of the IC. For additional input voltage filtering, a 0.1µF to 4.7µF
bypass capacitors can be placed in parallel with CIN, close to the VIN pins to shunt any high frequency noise to
ground. The output capacitors, COUT1 and COUT2, should also be placed close to the IC. Any copper trace
connections for the COUTX capacitors can increase the series resistance, which directly effects output voltage
ripple. The feedback network, resistors RFB1 and RFB2, should be kept close to the FB pin, and away from the
inductor to minimize copper trace connections that can inject noise into the system. Trace connections made to
the inductors and schottky diodes should be minimized to reduce power dissipation and increase overall
efficiency. For more detail on switching power supply layout considerations see Application Note AN-1149:
Layout Guidelines for Switching Power Supplies (SNVA021).
Application Information
Table 1. Some Recommended Inductors (Others May Be Used)
Manufacturer Inductor Contact Information
Coilcraft DO3316 and DO5022 series www.coilcraft.com
Coiltronics DRQ73 and CD1 series www.cooperet.com
Pulse P0751 and P0762 series www.pulseeng.com
Sumida CDRH8D28 and CDRH8D43 series www.sumida.com
Table 2. Some Recommended Input And Output Capacitors (Others May Be Used)
Manufacturer Capacitor Contact Information
Vishay Sprague 293D, 592D, and 595D series tantalum www.vishay.com
Taiyo Yuden High capacitance MLCC ceramic www.t-yuden.com
ESRD seriec Polymer Aluminum Electrolytic
Cornell Dubilier www.cde.com
SPV and AFK series V-chip series
High capacitance MLCC ceramic
Panasonic www.panasonic.com
EEJ-L series tantalum
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PGND
FB1
VC1
VBG
SS2
VC2
FB2
AGND
AGND
PGND
PGND
PGND
SW1
VIN
CB1 SHDN1
SS1
FSLCT
SHDN2
SW2
LM2717
L2
22 PH
D2
MBRS240
COUT2
68 PF
COUT1
3.3V OUT1
8V to 20V IN
5V OUT2
PGND
RFB1
59k
RFB2
20k
RF
*Connect CINA (pin
23) and CINB (pins
14,15) as close as
possible to the VIN
pins.
68 PF
COUT1A
1 PF
ceramic
L1
22 PH
D1
MBRS240
1 PF
CBOOT1
*CINA CIN
68 PF
U1
CSS1
CC1
CBG
CC2
CSS2
AGND
RC2
RC1
20k
10k
4.7 nF 1 nF
47 nF
4.7 nF
47 nF
VIN
VIN
CB2
AGND
*CINB
4.7 PF
ceramic 4.7 PF
ceramic
1 PF
CBOOT2
COUT2A
1 PF
ceramic
20.5k
PGND
FB1
VC1
VBG
SS2
VC2
FB2
AGND
AGND
PGND
PGND
PGND
SW1
VIN
CB1 SHDN1
SS1
FSLCT
SHDN2
SW2
LM2717
L2
22 PH
D2
MBRS240
COUT2
68 PF
COUT1
3.3V OUT1
17V to 20V IN
15V OUT2
PGND
RFB1
221k
RFB2
20k
RF
*Connect CINA (pin
23) and CINB (pins
14,15) as close as
possible to the VIN
pins.
68 PF
COUT1A
1 PF
ceramic
L1
22 PH
D1
MBRS240
4.7 nF
CBOOT1
*CINA CIN
68 PF
U1
CSS1
CC1
CBG
CC2
CSS2
AGND
RC2
RC1
20k
2k
4.7 nF 1 nF
47 nF
4.7 nF
47 nF
VIN
VIN
CB2
AGND
*CINB
4.7 PF
ceramic 4.7 PF
ceramic
1 PF
CBOOT2
COUT2A
1 PF
ceramic
20.5k
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SNVS253D –MAY 2005–REVISED MARCH 2013
Figure 12. 15V, 3.3V Output Application
Figure 13. 5V, 3.3V Output Application
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REVISION HISTORY
Changes from Revision C (March 2013) to Revision D Page
• Changed layout of National Data Sheet to TI format .......................................................................................................... 11
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PACKAGE OPTION ADDENDUM
www.ti.com 6-Feb-2020
Addendum-Page 1
PACKAGING INFORMATION
Orderable Device Status
(1)
Package Type Package
Drawing Pins Package
Qty Eco Plan
(2)
Lead/Ball Finish
(6)
MSL Peak Temp
(3)
Op Temp (°C) Device Marking
(4/5)
Samples
LM2717MT/NOPB ACTIVE TSSOP PW 24 61 Green (RoHS
& no Sb/Br) SN Level-1-260C-UNLIM -40 to 125 LM2717MT
LM2717MTX/NOPB ACTIVE TSSOP PW 24 2500 Green (RoHS
& no Sb/Br) SN Level-1-260C-UNLIM -40 to 125 LM2717MT
(1) The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2) RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of <=1000ppm threshold. Antimony trioxide based
flame retardants must also meet the <=1000ppm threshold requirement.
(3) MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
(4) There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.
(5) Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation
of the previous line and the two combined represent the entire Device Marking for that device.
(6) Lead/Ball Finish - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead/Ball Finish values may wrap to two lines if the finish
value exceeds the maximum column width.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
PACKAGE OPTION ADDENDUM
www.ti.com 6-Feb-2020
Addendum-Page 2
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device Package
Type Package
Drawing Pins SPQ Reel
Diameter
(mm)
Reel
Width
W1 (mm)
A0
(mm) B0
(mm) K0
(mm) P1
(mm) W
(mm) Pin1
Quadrant
LM2717MTX/NOPB TSSOP PW 24 2500 330.0 16.4 6.95 8.3 1.6 8.0 16.0 Q1
PACKAGE MATERIALS INFORMATION
www.ti.com 23-Sep-2013
Pack Materials-Page 1
*All dimensions are nominal
Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm)
LM2717MTX/NOPB TSSOP PW 24 2500 367.0 367.0 35.0
PACKAGE MATERIALS INFORMATION
www.ti.com 23-Sep-2013
Pack Materials-Page 2
www.ti.com
PACKAGE OUTLINE
C
22X 0.65
2X
7.15
24X 0.30
0.19
TYP
6.6
6.2
1.2 MAX
0.15
0.05
0.25
GAGE PLANE
-80
BNOTE 4
4.5
4.3
A
NOTE 3
7.9
7.7
0.75
0.50
(0.15) TYP
TSSOP - 1.2 mm max heightPW0024A
SMALL OUTLINE PACKAGE
4220208/A 02/2017
1
12 13
24
0.1 C A B
PIN 1 INDEX AREA
SEE DETAIL A
0.1 C
NOTES:
1. All linear dimensions are in millimeters. Any dimensions in parenthesis are for reference only. Dimensioning and tolerancing
per ASME Y14.5M.
2. This drawing is subject to change without notice.
3. This dimension does not include mold flash, protrusions, or gate burrs. Mold flash, protrusions, or gate burrs shall not
exceed 0.15 mm per side.
4. This dimension does not include interlead flash. Interlead flash shall not exceed 0.25 mm per side.
5. Reference JEDEC registration MO-153.
SEATING
PLANE
A 20
DETAIL A
TYPICAL
SCALE 2.000
www.ti.com
EXAMPLE BOARD LAYOUT
0.05 MAX
ALL AROUND 0.05 MIN
ALL AROUND
24X (1.5)
24X (0.45)
22X (0.65)
(5.8)
(R0.05) TYP
TSSOP - 1.2 mm max heightPW0024A
SMALL OUTLINE PACKAGE
4220208/A 02/2017
NOTES: (continued)
6. Publication IPC-7351 may have alternate designs.
7. Solder mask tolerances between and around signal pads can vary based on board fabrication site.
LAND PATTERN EXAMPLE
EXPOSED METAL SHOWN
SCALE: 10X
SYMM
SYMM
1
12 13
24
15.000
METAL
SOLDER MASK
OPENING METAL UNDER
SOLDER MASK SOLDER MASK
OPENING
EXPOSED METAL
EXPOSED METAL
SOLDER MASK DETAILS
NON-SOLDER MASK
DEFINED
(PREFERRED)
SOLDER MASK
DEFINED
www.ti.com
EXAMPLE STENCIL DESIGN
24X (1.5)
24X (0.45)
22X (0.65)
(5.8)
(R0.05) TYP
TSSOP - 1.2 mm max heightPW0024A
SMALL OUTLINE PACKAGE
4220208/A 02/2017
NOTES: (continued)
8. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate
design recommendations.
9. Board assembly site may have different recommendations for stencil design.
SOLDER PASTE EXAMPLE
BASED ON 0.125 mm THICK STENCIL
SCALE: 10X
SYMM
SYMM
1
12 13
24
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