LTC1709EG-8 Linear Technology, LTC1709EG-8 Datasheet
LTC1709EG-8
Specifications of LTC1709EG-8
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LTC1709EG-8 Summary of contents
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... ESR values. The LTC1709-8/LTC1709-9 implement two different VID tables compliant with VRM8.4 and VRM9.0 respectively. , LTC and LT are registered trademarks of Linear Technology Corporation. OPTI-LOOP is a trademark of Linear Technology Corporation ...
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... Sink/Source 5 A (Note 1.2V Ext Load) (Note (Note 5) EXTV Tied OUT OUT RUN/ 1.9V RUN/SS V Rising RUN/ ORDER PART TOP VIEW NUMBER TG1 LTC1709EG SW1 LTC1709EG BOOST1 BG1 7 30 EXTV INTV PGND 10 27 BG2 11 26 BOOST2 12 25 SW2 13 24 TG2 ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER V RUN/SS Pin Latchoff Arming RUN/SSLO I RUN/SS Discharge Current SCL I Shutdown Latch Disable Current SDLHO I Total Sense Pins Source Current SENSE DF Maximum Duty Factor MAX ...
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... Input Resistance IN Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note 2: The LTC1709EG is guaranteed to meet performance specifications from Specifications over the – operating temperature range are assured by design, characterization and correlation with statistical process controls. ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS Supply Current vs Input Voltage and Mode (Figure 12) 1000 ON 800 600 400 200 SHUTDOWN INPUT VOLTAGE (V) 170989 G04 Internal 5V LDO ...
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LTC1709-8/LTC1709 TYPICAL PERFOR A CE CHARACTERISTICS Load Regulation 0.0 FCB = 15V IN FIGURE 1 –0.1 –0.2 –0.3 –0 LOAD CURRENT (A) 1629 G13 Maximum Current Sense Threshold vs Temperature ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS Current Sense Pin Input Current vs Temperature OUT 125 –50 – 100 TEMPERATURE ( C) 170989 G20 Undervoltage Lockout vs ...
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LTC1709-8/LTC1709 CTIO S PLLIN (Pin 6): External Synchronization Input to Phase Detector. This pin is internally terminated to SGND with 50k . The phase-locked loop will force the rising top gate signal of controller 1 ...
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CTIO AL DIAGRA PLLIN PHASE DET f IN 50k PLLFLTR CLK1 OSCILLATOR CLK2 PGOOD – 0.86V + EAIN – + 0.74V – – ...
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LTC1709-8/LTC1709-9 U OPERATIO (Refer to Functional Diagram) Main Control Loop The LTC1709 uses a constant frequency, current mode step-down architecture with inherent current sharing. During normal operation, the top MOSFET is turned on each cycle when the oscillator sets the ...
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... OUT a maximum average output current I value less half the peak-to-peak ripple current, I PolyPhase is a trademark of Linear Technology Corporation. LTC1709-8/LTC1709-9 are chosen based on the required peak output and an input common SENSE ). The current com- ...
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LTC1709-8/LTC1709 APPLICATIO S I FOR ATIO Allowing a margin for variations in the LTC1709 and external component values yields 2(50mV/I ) SENSE MAX Operating Frequency The LTC1709 uses a constant frequency, phase-lockable architecture with the frequency ...
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U U APPLICATIO S I FOR ATIO Accepting larger values of I allows the use of low L inductances, but can result in higher output voltage ripple. A reasonable starting point for setting ripple current 0.4(I )/2, ...
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LTC1709-8/LTC1709 APPLICATIO S I FOR ATIO synchronous MOSFET losses are greatest at high input voltage when the top switch duty factor is low or during a short-circuit when the synchronous switch is on close to 100% of the ...
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U U APPLICATIO S I FOR ATIO Where f = operating frequency of each stage, C output capacitance and I RIPPLE ripple currents. The output ripple varies with input voltage since I function of input voltage. The output ripple will ...
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LTC1709-8/LTC1709 APPLICATIO S I FOR ATIO EXTV Connection CC The LTC1709 contains an internal P-channel MOSFET switch connected between the EXTV When the voltage applied to EXTV CC internal regulator is turned off and an internal switch closes, ...
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U U APPLICATIO S I FOR ATIO INTV when the SW pin is low. When the topside MOSFET CC turns on, the driver places the C voltage across the gate- B source of the desired MOSFET. This enhances the MOSFET ...
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LTC1709-8/LTC1709 APPLICATIO S I FOR ATIO Each VID digital input is pulled 40k resistor in series with a diode from V . Therefore, it must be BIAS grounded to get a digital low input, and ...
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U U APPLICATIO S I FOR ATIO If the overload occurs after start-up, the voltage on C continue charging and will provide additional time before latching off • 3V)/(1 2.5 • 10 LO2 SS This built-in ...
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LTC1709-8/LTC1709 APPLICATIO S I FOR ATIO The loop filter components ( current pulses from the phase detector and provide a stable input to the voltage controlled oscillator. The filter components C and R determine how ...
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U U APPLICATIO S I FOR ATIO losses are predicted from the DC resistances of the fuse (if used), MOSFET, inductor, current sense resistor, and input and output capacitor ESR. In continuous mode the average output ...
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LTC1709-8/LTC1709 APPLICATIO S I FOR ATIO estimated using the percentage of overshoot seen at this pin. The bandwidth can also be estimated by examining the rise time at the pin. The I TH shown in the Figure 1 ...
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U U APPLICATIO S I FOR ATIO Design Example As a design example, assume (nominal (max 1.8V 20A and f = 300kHz. OUT MAX A The inductance ...
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LTC1709-8/LTC1709 APPLICATIO S I FOR ATIO Using Figure 4, the RMS ripple current will be (20A)(0.23) = 4.6A INRMS RMS An input capacitor(s) with a 4.6A RMS is required. The output capacitor ripple current is calculated ...
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U U APPLICATIO S I FOR ATIO BOLD LINES INDICATE HIGH, SWITCHING CURRENT LINES. KEEP LINES TO A MINIMUM LENGTH. Figure 10. Instantaneous Current Path Flow in a Multiple Phase Switching Regulator Simplified ...
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LTC1709-8/LTC1709 APPLICATIO S I FOR ATIO The worst-case RMS ripple current for a single stage design peaks at an input voltage of twice the output voltage. The worst-case RMS ripple current for a two stage design results in ...
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... FLASH SHALL NOT EXCEED 0.254mm (0.010") PER SIDE Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. ...
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... Mobile VID, and Three Low-Current Modes LTC1735 High Efficiency Synchronous Step-Down Controller LTC1736 High Efficiency Synchronous Step-Down Controller with 5-Bit VID Adaptive Power and Burst Mode are trademarks of Linear Technology Corporation. Linear Technology Corporation 28 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 www.linear-tech.com ...