Datasheet

ManualsBrandsTEXAS INSTRUMENTS ManualsPMICsPMIC - DC/DC voltage regulator Boost, Flyback, SEPIC WSON 6

LM2735

www.ti.com

SNVS485F –JUNE 2007–REVISED APRIL 2013

LM2735/LM2735-Q1 520kHz/1.6MHz – Space-Efficient Boost and SEPIC DC-DC Regulator

Check for Samples: LM2735

FEATURES

DESCRIPTION

The LM2735 is an easy-to-use, space-efficient 2.1A

• Input Voltage Range 2.7V to 5.5V

low-side switch regulator ideal for Boost and SEPIC

• Output Voltage Range 3V to 24V

DC-DC regulation. It provides all the active functions

• 2.1A Switch Current over Full Temperature

to provide local DC/DC conversion with fast-transient

Range

response and accurate regulation in the smallest PCB

area. Switching frequency is internally set to either

• Current-Mode Control

520kHz or 1.6MHz, allowing the use of extremely

• Logic High Enable Pin

small surface mount inductor and chip capacitors

• Ultra Low Standby Current of 80 nA in

while providing efficiencies up to 90%. Current-mode

Shutdown

control and internal compensation provide ease-of-

use, minimal component count, and high-

• 170 mΩ NMOS Switch

performance regulation over a wide range of

• ±2% Feedback Voltage Accuracy

operating conditions. External shutdown features an

• Ease-of-Use, Small Total Solution Size

ultra-low standby current of 80 nA ideal for portable

applications. Tiny SOT-23, WSON, and MSOP-

– Internal Soft-Start

PowerPAD packages provide space-savings.

– Internal Compensation

Additional features include internal soft-start, circuitry

– Two Switching Frequencies

to reduce inrush current, pulse-by-pulse current limit,

and thermal shutdown.

– 520 kHz (LM2735-Y)

– 1.6 MHz (LM2735-X)

– Uses Small Surface Mount Inductors and

Chip Capacitors

– Tiny SOT-23, WSON, and MSOP-PowerPAD

Packages

• LM2735-Q1 is AEC-Q100 Grade 1 Qualified and

is Manufactured on an Automotive Grade Flow

APPLICATIONS

• LCD Display Backlighting For Portable

Applications

• OLED Panel Power Supply

• USB Powered Devices

• Digital Still and Video Cameras

• White LED Current Source

• Automotive

Please 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.

Products conform to specifications per the terms of the Texas

Instruments standard warranty. Production processing does not

necessarily include testing of all parameters.

Summary of content (58 pages)

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LM2735 www.ti.com SNVS485F – JUNE 2007 – REVISED APRIL 2013 LM2735/LM2735-Q1 520kHz/1.6MHz – Space-Efficient Boost and SEPIC DC-DC Regulator Check for Samples: LM2735 FEATURES DESCRIPTION • • • The LM2735 is an easy-to-use, space-efficient 2.1A low-side switch regulator ideal for Boost and SEPIC DC-DC regulation. It provides all the active functions to provide local DC/DC conversion with fast-transient response and accurate regulation in the smallest PCB area.
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LM2735 SNVS485F – JUNE 2007 – REVISED APRIL 2013 www.ti.com Typical Boost Application Circuit VIN 2.7V-5.5V L1 12V D1 R2 R3 4 C3 3 C2 2 5 R1 1 C1 GND Figure 1. Figure 2. Efficiency vs Load Current VO = 12V Connection Diagrams SW 1 5 VIN 4 EN PGND 1 6 SW VIN 2 5 AGND EN 3 4 FB GND 2 FB 3 Figure 3. 5-Pin SOT-23 (Top View) See Package Number DBV Figure 4. 6-Pin WSON (Top View) See Package Number NGG NC 1 8 NC PGND 2 7 SW VIN 3 6 AGND EN 4 5 FB Figure 5.
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LM2735 www.ti.com SNVS485F – JUNE 2007 – REVISED APRIL 2013 PIN DESCRIPTIONS - 5-PIN SOT-23 Pin Name 1 SW 2 GND Function Output switch. Connect to the inductor, output diode. Signal and power ground pin. Place the bottom resistor of the feedback network as close as possible to this pin. 3 FB Feedback pin. Connect FB to external resistor divider to set output voltage. 4 EN Shutdown control input. Logic high enables operation. Do not allow this pin to float or be greater than VIN + 0.3V.
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LM2735 SNVS485F – JUNE 2007 – REVISED APRIL 2013 www.ti.com 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. Absolute Maximum Ratings (1) (2) VIN -0.5V to 7V SW Voltage -0.5V to 26.5V FB Voltage -0.5V to 3.0V EN Voltage -0.5V to 7.0V ESD Susceptibility (3) 2kV Junction Temperature (4) 150°C Storage Temp.
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LM2735 www.ti.com SNVS485F – JUNE 2007 – REVISED APRIL 2013 Electrical Characteristics Limits in standard type are for TJ = 25°C only; limits in boldface type apply over the junction temperature range of (TJ = 40°C to 125°C). Minimum and Maximum limits are specified through test, design, or statistical correlation. Typical values represent the most likely parametric norm at TJ = 25°C, and are provided for reference purposes only. VIN = 5V unless otherwise indicated under the Conditions column.
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LM2735 SNVS485F – JUNE 2007 – REVISED APRIL 2013 www.ti.com Typical Performance Characteristics 6 Current Limit vs Temperature FB Pin Voltage vs Temperature Figure 6. Figure 7. Oscillator Frequency vs Temperature - "X" Oscillator Frequency vs Temperature - "Y" Figure 8. Figure 9. Typical Maximum Output Current vs VIN RDSON vs Temperature Figure 10. Figure 11.
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LM2735 www.ti.com SNVS485F – JUNE 2007 – REVISED APRIL 2013 Typical Performance Characteristics (continued) LM2735X Efficiency vs Load Current, Vo = 20V LM2735Y Efficiency vs Load Current, Vo = 20V Figure 12. Figure 13. LM2735X Efficiency vs Load Current, Vo = 12V LM2735Y Efficiency vs Load Current, Vo = 12V Figure 14. Figure 15. Output Voltage Load Regulation Output Voltage Line Regulation Figure 16. Figure 17.
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LM2735 SNVS485F – JUNE 2007 – REVISED APRIL 2013 www.ti.com Simplified Internal Block Diagram EN VIN ThermalSHDN Control Logic + UVLO = 2.3V Oscillator Corrective - Ramp SW cv S R R Q 1.6 MHz + + - FB VREF = 1.255V NMOS Internal Compensation ILIMIT Soft-Start ISENSE-AMP + - GND Figure 18. Simplified Block Diagram APPLICATION INFORMATION THEORY OF OPERATION The LM2735 is a constant frequency PWM boost regulator IC that delivers a minimum of 2.1A peak switch current.
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LM2735 www.ti.com SNVS485F – JUNE 2007 – REVISED APRIL 2013 I L (t) + VL (t) - D1 L1 I C (t) + VIN + Q1 VSW( t ) Control VO(t) C1 - Figure 19. Simplified Schematic VO + VD Vsw (t) t VIN VL(t) t VIN - VOUT - VD I L (t) iL t I DIODE (t) t ( iL - - i OUT ) I Capacitor (t) t - i OUT 'v VOUT (t) DTS TS Figure 20.
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LM2735 SNVS485F – JUNE 2007 – REVISED APRIL 2013 www.ti.com CURRENT LIMIT The LM2735 uses cycle-by-cycle current limiting to protect the internal NMOS switch. It is important to note that this current limit will not protect the output from excessive current during an output short circuit. The input supply is connected to the output by the series connection of an inductor and a diode. If a short circuit is placed on the output, excessive current can damage both the inductor and diode.
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LM2735 www.ti.com SNVS485F – JUNE 2007 – REVISED APRIL 2013 Therefore: VOUT - VIN D= VOUT (2) Power losses due to the diode (D1) forward voltage drop, the voltage drop across the internal NMOS switch, the voltage drop across the inductor resistance (RDCR) and switching losses must be included to calculate a more accurate duty cycle (See Calculating Efficiency, and Junction Temperature for a detailed explanation).
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LM2735 SNVS485F – JUNE 2007 – REVISED APRIL 2013 www.ti.com Because of the operating frequency of the LM2735, ferrite based inductors are preferred to minimize core losses. This presents little restriction since the variety of ferrite-based inductors is huge. Lastly, inductors with lower series resistance (DCR) will provide better operating efficiency. For recommended inductors see Example Circuits.
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LM2735 www.ti.com SNVS485F – JUNE 2007 – REVISED APRIL 2013 VO C3 R2 VFB R LOAD R1 Figure 22. Setting Vout A good value for R1 is 10kΩ. § VOUT · - 1¸¸ x R1 R 2 = ¨¨ © VREF ¹ (9) COMPENSATION The LM2735 uses constant frequency peak current mode control. This mode of control allows for a simple external compensation scheme that can be optimized for each application.
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LM2735 SNVS485F – JUNE 2007 – REVISED APRIL 2013 www.ti.com 80 gm-Pole 60 RC-Pole 40 Vi = 5V Vo = 12V Io = 500 mA Co = 10 mF Lo = 5 mH 180 90 D = 0.625 Cf = 220 pF gm-zero 0 0 Fz-cf = 8 kHz RHP-Zero = 107 kHz -20 Fp-cf = 77 kHz Fp-rc = 660 Hz -90 -40 Ext (Cf) -Zero -60 Ext (Cf)-Pole RHP-Zero -180 -80 10 100 1k 10k 100k 1M dB 20 FREQUENCY Figure 24. LM2735 With External Compensation The simplest method to determine the compensation component value is as follows.
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LM2735 www.ti.com SNVS485F – JUNE 2007 – REVISED APRIL 2013 VO R2 C3 VFB R LOAD R1 Figure 25. Setting External Pole-Zero FZERO - CF = 1 2S(R2 x C3) (14) There is an associated pole with the zero that was created in the above equation. FPOLE - CF = 1 2S((R1 R2) x C3) (15) It is always higher in frequency than the zero. A right-half plane zero (RHPZ) is inherent to all boost converters.
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LM2735 SNVS485F – JUNE 2007 – REVISED APRIL 2013 www.ti.com Below is an example of a good thermal & electrical PCB design. This is very similar to our LM2735 demonstration boards that are obtainable via the Texas Instruments website. The demonstration board consists of a two layer PCB with a common input and output voltage application. Most of the routing is on the top layer, with the bottom layer consisting of a large ground plane.
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LM2735 www.ti.com SNVS485F – JUNE 2007 – REVISED APRIL 2013 Definitions Heat energy is transferred from regions of high temperature to regions of low temperature via three basic mechanisms: radiation, conduction and convection. Radiation Electromagnetic transfer of heat between masses at different temperatures. Conduction Transfer of heat through a solid medium. Convection Transfer of heat through the medium of a fluid; typically air.
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LM2735 SNVS485F – JUNE 2007 – REVISED APRIL 2013 • www.ti.com PCB variables (copper weight, thermal via’s, layers component placement). It would be wrong to assume that the top case temperature is the proper temperature when calculating RθJC value. The RθJC value represents the thermal impedance of all six sides of a package, not just the top side. This document will refer to a thermal impedance called RψJC. RψJC represents a thermal impedance associated with just the top case temperature.
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LM2735 www.ti.com SNVS485F – JUNE 2007 – REVISED APRIL 2013 RTCASE-AMB TCASE CTCASE-AMB RTJ-CASE CTJ-CASE INTERNAL SMALL PDISS LARGE PDISS-TOP TAMBIENT PDISS-PCB TJUNCTION RTJ-PCB CTJ-PCB DEVICE EXTERNAL PDISS RTPCB-AMB TPCB CTPCB-AMB PCB Figure 29. Associated Thermal Model Calculating Efficiency, and Junction Temperature The complete LM2735 DC/DC converter efficiency (η) can be calculated in the following manner.
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LM2735 SNVS485F – JUNE 2007 – REVISED APRIL 2013 VOUT VIN www.ti.
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LM2735 www.ti.com SNVS485F – JUNE 2007 – REVISED APRIL 2013 'i I I sw(t) t Figure 30. LM2735 Switch Current Isw-rms = IIND D x 1 + 1 3 'i IIND 2 | IIND D PIND = IIN2 x RIND-DCR (small ripple approximation) PCOND-NFET = IIN2 x RDSON x D (28) (29) 2 §I · PCOND - NFET = ¨ O ¸ x RDSON x D © D' ¹ (30) The value for should be equal to the resistance at the junction temperature you wish to analyze. As an example, at 125°C and VIN = 5V, RDSON = 250 mΩ (See typical graphs for value).
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LM2735 SNVS485F – JUNE 2007 – REVISED APRIL 2013 www.ti.com Table 1. Typical Switch-Node Rise and Fall Times VIN VOUT TRISE TFALL 3V 5V 6nS 4nS 5V 12V 6nS 5nS 3V 12V 7nS 5nS 5V 18V 7nS 5nS Quiescent Power Losses IQ is the quiescent operating current, and is typically around 4mA. PQ = IQ x VIN (34) Example Efficiency Calculation: Table 2. Operating Conditions VIN 5V VOUT 12V IOUT 500mA VD 0.4V FSW 1.60MHz IQ 4mA TRISE 6nS TFALL 5nS RDSon 250mΩ RDCR 50mΩ D 0.
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LM2735 www.ti.com SNVS485F – JUNE 2007 – REVISED APRIL 2013 Total Power Losses are: Table 3. Power Loss Tabulation VIN 5V VOUT 12V IOUT 500mA POUT 6W PDIODE 236mW VD 0.4V FSW 1.6MHz TRISE 6nS PSWR 80mW TFALL 5nS PSWF 70mW IQ 4mA PQ 20mW RDSon 250mΩ PCOND 305mW RDCR 75mΩ PIND 145mW D 0.
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LM2735 SNVS485F – JUNE 2007 – REVISED APRIL 2013 www.ti.com Example from previous calculations: Pdiss = 475 mW Ta @ Shutdown = 139°C Tc @ Shutdown = 155°C TJ - TA TJ - TCase-Top : R
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LM2735 www.ti.com SNVS485F – JUNE 2007 – REVISED APRIL 2013 SEPIC Converter The LM2735 can easily be converted into a SEPIC converter. A SEPIC converter has the ability to regulate an output voltage that is either larger or smaller in magnitude than the input voltage. Other converters have this ability as well (CUK and Buck-Boost), but usually create an output voltage that is opposite in polarity to the input voltage.
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LM2735 SNVS485F – JUNE 2007 – REVISED APRIL 2013 www.ti.com Applying Charge balance on C1: D' (Vo ) VC1 = D (53) Since there are no DC voltages across either inductor, and capacitor C6 is connected to Vin through L1 at one end, or to ground through L2 on the other end, we can say that VC1 = VIN (54) Therefore: VIN = D' (Vo ) D (55) This verifies the original conversion ratio equation. It is important to remember that the internal switch current is equal to IL1 and IL2. During the D interval.
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LM2735 www.ti.
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LM2735 SNVS485F – JUNE 2007 – REVISED APRIL 2013 www.ti.com SEPIC Converter PCB Layout The layout guidelines described for the LM2735 Boost-Converter are applicable to the SEPIC Converter. Below is a proper PCB layout for a SEPIC Converter. CIN PCB VIN PGND FB L1 EN 4 3 AGND VIN 5 2 PGND SW 6 1 CIN COUT D1 VO C6 L2 Figure 35.
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LM2735 www.ti.com SNVS485F – JUNE 2007 – REVISED APRIL 2013 WSON Package The LM2735 packaged in the 6–pin WSON: Figure 36. Internal WSON Connection For certain high power applications, the PCB land may be modified to a "dog bone" shape (see Figure 37). Increasing the size of ground plane, and adding thermal vias can reduce the RθJA for the application. COPPER PGND 1 6 SW Vin 2 5 AGND EN 3 4 FB COPPER Figure 37.
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LM2735 SNVS485F – JUNE 2007 – REVISED APRIL 2013 www.ti.com LM2735X SOT-23 Design Example 1 L1 3 4 FB EN R3 2 GND VIN 12V 1 5 SW Vin D1 C1 R2 C2 C3 R LOAD R1 Figure 38. LM2735X (1.6MHz): Vin = 5V, Vout = 12V @ 350mA 30 Part ID Part Value Manufacturer U1 2.1A Boost Regulator TI Part Number LM2735XMF C1, Input Cap 22µF, 6.3V, X5R TDK C2012X5R0J226M C2 Output Cap 10µF, 25V, X5R TDK C3216X5R1E106M C3 Comp Cap 330pF TDK C1608X5R1H331K D1, Catch Diode 0.
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LM2735 www.ti.com SNVS485F – JUNE 2007 – REVISED APRIL 2013 LM2735Y SOT-23 Design Example 2 L1 3 4 R3 FB EN 2 GND VIN 12V 1 5 SW Vin D1 C1 R2 C2 C3 R LOAD R1 Figure 39. LM2735Y (520kHz): Vin = 5V, Vout = 12V @ 350mA Part ID Part Value Manufacturer U1 2.1A Boost Regulator TI Part Number LM2735YMF C1, Input Cap 22µF, 6.3V, X5R TDK C2012X5R0J226M C2 Output Cap 10µF, 25V, X5R TDK C3216X5R1E106M C3 Comp Cap 330pF TDK C1608X5R1H331K D1, Catch Diode 0.
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LM2735 SNVS485F – JUNE 2007 – REVISED APRIL 2013 www.ti.com LM2735X WSON Design Example 3 VIN L1 LM2735 R3 C1 C2 D1 1 6 2 5 3 4 R2 C5 RLOAD C3 C4 R1 Figure 40. LM2735X (1.6MHz): Vin = 3.3V, Vout = 12V @ 350mA 32 Part ID Part Value Manufacturer U1 2.1A Boost Regulator TI LM2735XSD C1 Input Cap 22µF, 6.
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LM2735 www.ti.com SNVS485F – JUNE 2007 – REVISED APRIL 2013 LM2735Y WSON Design Example 4 VIN L1 LM2735 R3 C1 C2 D1 1 6 2 5 3 4 R2 C5 RLOAD C3 C4 R1 Figure 41. LM2735Y (520kHz): Vin = 3.3V, Vout = 12V @ 350mA Part ID Part Value Manufacturer U1 2.1A Boost Regulator TI LM2735YSD C1 Input Cap 22µF, 6.
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LM2735 SNVS485F – JUNE 2007 – REVISED APRIL 2013 www.ti.com LM2735Y MSOP-PowerPAD Design Example 5 VIN L1 D1 R3 LM2735 1 NC C1 C2 NC 8 2 PGND R2 SW 7 3 VIN C5 AGND 6 4 EN R LOAD FB 5 C3 C4 R1 Figure 42. LM2735Y (520kHz): Vin = 3.3V, Vout = 12V @ 350mA 34 Part ID Part Value Manufacturer U1 2.1A Boost Regulator TI Part Number LM2735YMY C1 Input Cap 22µF, 6.
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LM2735 www.ti.com SNVS485F – JUNE 2007 – REVISED APRIL 2013 LM2735X SOT-23 Design Example 6 L1 3 4 R3 FB SHDN 2 GND VIN 5V 1 5 SW Vin D1 C1 R2 C2 C3 R LOAD R1 Figure 43. LM2735X (1.6MHz): Vin = 3V, Vout = 5V @ 500mA Part ID Part Value Manufacturer U1 2.1A Boost Regulator TI Part Number LM2735XMF C1, Input Cap 10µF, 6.3V, X5R TDK C2012X5R0J106K C2, Output Cap 10µF, 6.3V, X5R TDK C2012X5R0J106K C3 Comp Cap 1000pF TDK C1608X5R1H102K D1, Catch Diode 0.
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LM2735 SNVS485F – JUNE 2007 – REVISED APRIL 2013 www.ti.com LM2735Y SOT-23 Design Example 7 L1 3 4 FB SHDN R3 2 GND VIN 5V 1 5 SW Vin D1 C1 R2 C2 C3 R LOAD R1 Figure 44. LM2735Y (520kHz): Vin = 3V, Vout = 5V @ 750mA 36 Part ID Part Value Manufacturer U1 2.1A Boost Regulator TI Part Number LM2735YMF C1 Input Cap 22µF, 6.3V, X5R TDK C2012X5R0J226M C2 Output Cap 22µF, 6.3V, X5R TDK C2012X5R0J226M C3 Comp Cap 1000pF TDK C1608X5R1H102K D1, Catch Diode 0.
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LM2735 www.ti.com SNVS485F – JUNE 2007 – REVISED APRIL 2013 LM2735X SOT-23 Design Example 8 L1 3 4 R3 FB SHDN 2 GND VIN 20V 1 5 SW Vin D1 C1 R2 C2 C3 R LOAD R1 Figure 45. LM2735X (1.6MHz): Vin = 3.3V, Vout = 20V @ 100mA Part ID Part Value Manufacturer U1 2.1A Boost Regulator TI Part Number LM2735XMF C1, Input Cap 22µF, 6.3V, X5R TDK C2012X5R0J226M C2, Output Cap 4.7µF, 25V, X5R TDK C3216X5R1E475K C3 Comp Cap 470pF TDK C1608X5R1H471K D1, Catch Diode 0.
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LM2735 SNVS485F – JUNE 2007 – REVISED APRIL 2013 www.ti.com LM2735Y SOT-23 Design Example 9 L1 3 4 R3 FB SHDN 2 GND VIN 20V 1 5 SW Vin D1 C1 R2 C2 C3 R LOAD R1 Figure 46. LM2735Y (520kHz): Vin = 3.3V, Vout = 20V @ 100mA 38 Part ID Part Value Manufacturer U1 2.1A Boost Regulator TI Part Number LM2735YMF C1 Input Cap 22µF, 6.3V, X5R TDK C2012X5R0J226M C2 Output Cap 10µF, 25V, X5R TDK C3216X5R1E106M C3 Comp Cap 470pF TDK C1608X5R1H471K D1, Catch Diode 0.
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LM2735 www.ti.com SNVS485F – JUNE 2007 – REVISED APRIL 2013 LM2735X WSON Design Example 10 VIN L1 LM2735 R3 C1 C2 D1 1 6 2 5 3 4 R2 C5 RLOAD C3 C4 R1 Figure 47. LM2735X (1.6MHz): Vin = 3.3V, Vout = 20V @ 150mA Part ID Part Value Manufacturer U1 2.1A Boost Regulator TI Part Number LM2735XSD C1 Input Cap 22µF, 6.3V, X5R TDK C2012X5R0J226M C2 Input Cap 22µF, 6.
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LM2735 SNVS485F – JUNE 2007 – REVISED APRIL 2013 www.ti.com LM2735Y WSON Design Example 11 VIN L1 LM2735 R3 C1 C2 D1 1 6 2 5 3 4 R2 C5 RLOAD C3 C4 R1 Figure 48. LM2735Y (520kHz): Vin = 3.3V, Vout = 20V @ 150mA 40 Part ID Part Value Manufacturer U1 2.1A Boost Regulator TI Part Number LM2735YSD C1 Input Cap 10µF, 6.3V, X5R TDK C2012X5R0J106K C2 Input Cap 10µF, 6.
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LM2735 www.ti.com SNVS485F – JUNE 2007 – REVISED APRIL 2013 LM2735X WSON SEPIC Design Example 12 VIN VO L1 D1 C6 LM2735 C1 C2 1 6 2 5 3 4 L2 R2 R3 C5 C4 C3 R1 Figure 49. LM2735X (1.6MHz): Vin = 2.7V - 5V, Vout = 3.3V @ 500mA Part ID Part Value Manufacturer Part Number U1 2.1A Boost Regulator TI LM2735XSD C1 Input Cap 22µF, 6.
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LM2735 SNVS485F – JUNE 2007 – REVISED APRIL 2013 www.ti.com LM2735Y MSOP-PowerPAD SEPIC Design Example 13 VIN L1 D1 C6 R3 LM2735 1 NC C1 C2 NC 8 2 PGND SW 7 3 VIN R2 L2 C5 AGND 6 4 EN R LOAD FB 5 C4 C3 R1 Figure 50. LM2735Y (520kHz): Vin = 2.7V - 5V, Vout = 3.3V @ 500mA 42 Part ID Part Value Manufacturer U1 2.1A Boost Regulator TI Part Number LM2735YMY C1 Input Cap 22µF, 6.
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LM2735 www.ti.com SNVS485F – JUNE 2007 – REVISED APRIL 2013 LM2735X SOT-23 LED Design Example 14 L1 R3 3 FB 2 4 SHDN Vin C2 D1 1 SW 5 Vin C1 R1 R2 DIM - CTRL Figure 51. LM2735X (1.6MHz): Vin = 2.7V - 5V, Vout = 20V @ 50mA Part ID Part Value Manufacturer Part Number U1 2.1A Boost Regulator TI LM2735XMF C1 Input Cap 22µF, 6.3V, X5R TDK C2012X5R0J226M C2 Output Cap 4.7µF, 25V, X5R TDK C3216JB1E475K D1, Catch Diode 0.4Vf Schottky 500mA, 30VR Vishay MBR0530 L1 15µH 1.
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LM2735 SNVS485F – JUNE 2007 – REVISED APRIL 2013 www.ti.com LM2735Y WSON FlyBack Design Example 15 + 12V D1 R2 Cf T1 V IN C2 R LOAD R1 LM2735 R3 1 C3 6 R LOAD C1 2 5 3 4 D2 - 12V Figure 52. LM2735Y (520kHz): Vin = 5V, Vout = ±12V 150mA Part ID Part Value Manufacturer U1 2.1A Boost Regulator TI Part Number LM2735YSD C1 Input Cap 22µF, 6.
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LM2735 www.ti.com SNVS485F – JUNE 2007 – REVISED APRIL 2013 LM2735X SOT-23 LED Design Example 16 VRAIL > 5.5V Application D1 L1 VPWR R2 LM2735 EN C1 R4 4 R3 C4 3 2 5 D2 C2 1 R1 C3 Figure 53. LM2735X (1.6MHz): VPWR = 9V, Vout = 12V @ 500mA Part ID Part Value Manufacturer U1 2.1A Boost Regulator TI Part Number LM2735XMF C1, Input Cap 10µF, 6.3V, X5R TDK C2012X5R0J106K C2, Output Cap 10µF, 25V, X5R TDK C3216X5R1E106M C3 VIN Cap 0.1µF, 6.
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LM2735 SNVS485F – JUNE 2007 – REVISED APRIL 2013 www.ti.com LM2735X SOT-23 LED Design Example 17 Two Input Voltage Rail Application D1 L1 VPWR LM2735 EN C1 4 R3 R2 3 2 VIN 5 C4 R1 1 C2 C3 Figure 54. LM2735X (1.6MHz): VPWR = 9V in = 2.7V - 5.5V, Vout = 12V @ 500mA 46 Part ID Part Value Manufacturer Part Number U1 2.1A Boost Regulator TI LM2735XMF C1, Input Cap 10µF, 6.3V, X5R TDK C2012X5R0J106K C2, Output Cap 10µF, 25V, X5R TDK C3216X5R1E106M C3 VIN Cap 0.1µF, 6.
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LM2735 www.ti.com SNVS485F – JUNE 2007 – REVISED APRIL 2013 REVISION HISTORY Changes from Revision E (April 2013) to Revision F • Page Changed layout of National Data Sheet to TI format ..........................................................................................................
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PACKAGE OPTION ADDENDUM www.ti.
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PACKAGE OPTION ADDENDUM www.ti.
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PACKAGE OPTION ADDENDUM www.ti.
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PACKAGE MATERIALS INFORMATION www.ti.com 8-Apr-2013 TAPE AND REEL INFORMATION *All dimensions are nominal Device Package Package Pins Type Drawing SPQ LM2735XMF/NOPB SOT-23 LM2735XMFX/NOPB LM2735XMY/NOPB Reel Reel A0 Diameter Width (mm) (mm) W1 (mm) DBV 5 1000 178.0 SOT-23 DBV 5 3000 MSOPPower PAD DGN 8 1000 LM2735XMYX/NOPB MSOPPower PAD DGN 8 B0 (mm) K0 (mm) P1 (mm) 8.4 3.2 3.2 1.4 4.0 178.0 8.4 3.2 3.2 1.4 178.0 12.4 5.3 3.4 1.4 3500 330.0 12.4 5.3 3.
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PACKAGE MATERIALS INFORMATION www.ti.com 8-Apr-2013 Device Package Package Pins Type Drawing SPQ Reel Reel A0 Diameter Width (mm) (mm) W1 (mm) B0 (mm) K0 (mm) P1 (mm) W Pin1 (mm) Quadrant PAD LM2735YQMF/NOPB SOT-23 DBV 5 1000 178.0 LM2735YQMFX/NOPB LM2735YQSD/NOPB 8.4 3.2 3.2 1.4 4.0 SOT-23 DBV 5 3000 WSON NGG 6 1000 LM2735YQSDX/NOPB WSON NGG 6 LM2735YSD/NOPB WSON NGG LM2735YSDX/NOPB WSON NGG 8.0 Q3 178.0 8.4 3.2 3.2 1.4 178.0 12.4 3.3 3.3 1.0 4.0 8.
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PACKAGE MATERIALS INFORMATION www.ti.com 8-Apr-2013 Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm) LM2735YMFX/NOPB SOT-23 DBV 5 3000 210.0 185.0 35.0 LM2735YMY/NOPB MSOP-PowerPAD DGN 8 1000 210.0 185.0 35.0 LM2735YMYX/NOPB MSOP-PowerPAD DGN 8 3500 367.0 367.0 35.0 LM2735YQMF/NOPB SOT-23 DBV 5 1000 210.0 185.0 35.0 LM2735YQMFX/NOPB SOT-23 DBV 5 3000 210.0 185.0 35.0 LM2735YQSD/NOPB WSON NGG 6 1000 210.0 185.0 35.
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MECHANICAL DATA DGN0008A MUY08A (Rev A) BOTTOM VIEW www.ti.
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MECHANICAL DATA NGG0006A SDE06A (Rev A) www.ti.
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