ltc3713 Linear Technology Corporation, ltc3713 Datasheet
ltc3713
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ltc3713 Summary of contents
Page 1
... F 3713 F01a C : PANASONIC EEFUEOD271R MBR0520 OUT 4.7 H L1: (A) PANASONIC ETQP6FIR8BFA (B) TOKO D104C-1.8 H M1, M2: (A) IRF7822, (B) IRF7811A LTC3713 Low Input Voltage, High Power SENSE U . The controller uses IN and V . The LTC3713 IN OUT Efficiency vs Load Current 100 ...
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... RNG FB1 0.84V RNG FB1 V = INTV , V = 0.84V RNG CC FB1 RUN/SS Pin Rising RUN/SS Pin Falling U W ORDER PART TOP VIEW NUMBER 1 BOOST LTC3713EG 3 SW1 SENSE 21 – 5 SENSE 20 6 PGND1 INTV IN1 10 15 ...
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... T J dissipation P as follows: D LTC3713EG • 130 C/ Note 3: The LTC3713 is tested in a feedback loop that adjusts V The denotes specifications which apply over the full operating = 15V 1.5V unless otherwise noted. A IN1 IN2 CONDITIONS ...
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... LTC3713 W U TYPICAL PERFOR A CE CHARACTERISTICS Transient Response V OUT 100mV/DIV I L 5A/DIV 50 s/DIV 3713 G01 LOAD STEP 3. 1.25V OUT FCB = 0V FIGURE 1 CIRCUIT Boost Converter Oscillator Frequency vs Temperature 2. 1. 1.5V IN 1.25 1.00 0.75 0.50 0.25 0 –50 – TEMPERATURE ( C) 3713 G04 V , Feedback Pin Voltage FB2 1 ...
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... TEMPERATURE ( C) Maximum Current Sense Threshold vs RUN/SS Voltage 150 RNG 125 100 1.5 2 2.5 3 RUN/SS VOLTAGE (V) LTC3713 On-Time vs I Current ON 10k 1k 100 4.5 5.0 I CURRENT ( A) ON 3713 G12 Current Limit Foldback 150 RNG 125 100 75 50 ...
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... LTC3713 W U TYPICAL PERFOR A CE CHARACTERISTICS Feedback Reference Voltage vs Temperature 0.82 0.81 0.80 0.79 0.78 –50 – 100 125 TEMPERATURE ( C) 3713 G20 Current Sense Threshold Voltage 300 RNG 200 1.4V 1V 0.7V 100 0.5V 0 –100 –200 0 0.5 1.0 1.5 2.0 2.5 I VOLTAGE (V) TH 3713 G23 RUN/SS Latchoff Thresholds vs Temperature 5.0 4.5 LATCHOFF ENABLE 4 ...
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... Error Amplifier Feedback Input. This pin FB1 connects the error amplifier input to an external resistive divider from V . OUT SHDN (Pin 10): Shutdown, Active Low. Tie more to enable boost converter portion of the LTC3713. Ground to shut down. V (Pin 12): Boost Converter Feedback. The V FB2 connected to INTV voltage on INTV ...
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... LTC3713 CTIO AL DIAGRA 0.7V 2.4V V VON t = (10pF ION 20k + I CMP – 1.4V V RNG 4 0.7V 3 240k THB 0.8V – – 0. IN2 R5 40k V OUT2 R7 (EXTERNAL) V FB2 Q1 FB2 12 R8 (EXTERNAL) 11 SGND2 FCB 4.7V + – 0.8V – ...
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... U OPERATIO Main Control Loop The LTC3713 is a current mode controller for DC/DC step-down converters designed to operate from low input voltages. It incorporates a boost converter with a buck regulator. Buck Regulator Operation In normal operation, the top MOSFET is turned on for a fixed interval determined by a one-shot timer OST. When ...
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... The maximum allowed sense voltage is about 1.33 times this nominal value. Connecting the SENSE The LTC3713 can be used with or without a sense resistor. When using a sense resistor placed between the is chosen with source of the bottom MOSFET M2 and ground. Connect ...
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... R : OS1 OS2 to avoid inter- OUT The power dissipated by the top and bottom MOSFETs strongly depends upon their respective duty cycles and the load current. When the LTC3713 is operating in continuous mode, the duty cycles for the MOSFETs are TOP (BR)DSS , reverse DS(ON) ...
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... MOSFET switching losses but requires larger inductance and/or capacitance in order to maintain low output ripple voltage. The operating frequency of LTC3713 applications is deter- mined implicitly by the one-shot timer that controls the on-time t of the top MOSFET switch. The on-time is set ...
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... Dry tantalum, special polymer, aluminum electrolytic and ceramic capacitors are all available in surface mount packages. Special polymer capacitors offer very low ESR but have lower capacitance density than other types. Kool registered trademark of Magnetics, Inc. LTC3713 Selection OUT is required to filter the square IN ...
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... Minimum Off-time and Dropout Operation The minimum off-time t time that the LTC3713 is capable of turning on the bottom MOSFET, tripping the current comparator and turning the MOSFET back off. This time is generally about 250ns. The minimum off-time limit imposes a maximum duty cycle of ...
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... External Gate Drive Buffers The LTC3713 drivers are adequate for driving up to about 30nC into MOSFET switches with RMS currents of 50mA. Applications with larger MOSFET switches or operating at frequencies requiring greater RMS currents will benefit from using external gate drive buffers such as the LTC1693. ...
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... INTV Supply CC The 5V supply that powers the drivers and internal cir- cuitry within the LTC3713 can be supplied by either an internal P-channel low dropout regulator if V than 5V or the internal boost regulator if V The INTV pin can supply up to 50mA RMS and must be CC bypassed to ground with a minimum of 4 ...
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... C above ambient with I LIMIT and double check the assumed T P BOT (0.24W)(50 C/ Now check the power dissipation of the top MOSFET at current limit with LTC3713 = 1.8V to 3.3V 1.25V 100mV, IN OUT = 6A 300kHz. First, calculate the timing = OUT ( . – ...
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... CMDSH RUN/SS BOOST 0. PGOOD SW1 SENSE RNG 5 20 – FCB SENSE PGND1 TH LTC3713 7 18 SGND1 BG C VCC INTV X5R FB1 IN1 10 15 SHDN V IN2 C IN2 4 SGND2 PGND2 ...
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... IN OUT compact area. It may help to have some components on the bottom side of the board. • Place LTC3713 chip with Pins facing the power components. Keep the components connected to Pins close to LTC3713 (noise sensitive components). • Use an immediate via to connect the components to ground plane including SGND and PGND of LTC3713 ...
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... Bus Terminator D B CMDSH-3 24 RUN/SS BOOST 0. PGOOD SW1 SENSE RNG 20 – FCB SENSE 19 I PGND1 TH LTC3713 18 SGND1 BG C VCC INTV 6.3V 1.15k ON CC X5R FB1 IN1 15 SHDN V IN2 C IN2 4 SGND2 PGND2 XR5 4 ...
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... 330k V V FB1 IN1 10 15 SHDN V IN2 11 14 SGND2 PGND2 SW2 FB2 10k 37. 1000pF LTC3713 + C C INA INB 22 F 470 F X5R 2 B 6.3V IRF7811A D2 B340A OUT M2 470 F IRF7811A 2 D1 B340A 4.7 F IN2 X5R, 6 ...
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... RUN/SS BOOST 0. PGOOD SW1 SENSE RNG 5 20 – FCB SENSE PGND1 TH 1 LTC3713 7 18 SGND1 BG C VCC 4 INTV X5R FB1 IN1 10 15 SHDN V IN2 C IN2 SGND2 ...
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... Plastic SSOP (5.3mm) (Reference LTC DWG # 05-08-1640) 1.25 0. 5.3 – 5.7 0.65 BSC – 8 0.65 (.0256) BSC 0.22 – 0.38 (.009 – .015) LTC3713 7.90 – 8.50* (.311 – .335 7.40 – 8.20 (.291 – .323) 2.0 (.079) 0.05 (.002) G24 SSOP 0802 3713fa 23 ...
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... D 0.1 F CMDSH RUN/SS BOOST C 0. PGOOD SW1 SENSE RNG 5 20 – FCB SENSE PGND1 TH LTC3713 7 18 SGND1 VCC 330k 4 INTV X5R FB1 IN1 10 15 SHDN V IN2 C IN2 ...