LTC1735CF#TRPBF Linear Technology, LTC1735CF#TRPBF Datasheet
LTC1735CF#TRPBF
Specifications of LTC1735CF#TRPBF
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LTC1735CF#TRPBF Summary of contents
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... The operating current level is user-programmable via an external current sense resistor. Wide input supply range allows operation from 4V to 30V (36V maximum). , LTC and LT are registered trademarks of Linear Technology Corporation. Burst Mode and OPTI-LOOP are trademarks of Linear Technology Corporation. C OSC ...
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LTC1735 ABSOLUTE AXI U RATI GS Input Supply Voltage (V ).........................36V to – 0.3V IN Topside Driver Supply Voltage (BOOST)....42V to – 0.3V Switch Voltage (SW) ....................................36V to – 5V EXTV Voltage ...........................................7V to – 0.3V CC ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER V Feedback Overvoltage Lockout OVL I Input DC Supply Current Q Normal Mode Shutdown V Run Pin Start Threshold RUN/SS V Run Pin Begin Latchoff Threshold RUN/SS I Soft-Start ...
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LTC1735 ELECTRICAL CHARACTERISTICS Note 3: The LTC1735 is tested in a feedback loop that servos V the balance point for the error amplifier (V = 1.2V). ITH Note 4: Dynamic supply current is higher due to the gate charge being ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS Input and Shutdown Currents vs Input Voltage 500 EXTV OPEN CC 400 300 200 SHUTDOWN 100 EXTV = INPUT VOLTAGE (V) 1735 ...
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LTC1735 W U TYPICAL PERFOR A CE CHARACTERISTICS SENSE Pins Total Source Current 100 50 0 –50 –100 COMMON MODE VOLTAGE (V) SENSE 1735 G16 Oscillator Frequency vs Temperature 300 C = 47pF OSC 290 ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS V OUT(RIPPLE) (Burst Mode Operation 1.5A FIGURE 1 LOAD V OUT 20mV/DIV I L 5A/DIV 1735 G27 FCB = 5V 5 s/DIV V = 15V 1.6V OUT Start-Up ...
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LTC1735 CTIO Receives the feedback voltage from an external OSENSE resistive divider across the output. – SENSE : The (–) Input to the Current Comparator. + SENSE : The (+) Input to ...
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CTIO AL DIAGRA C OSC PGOOD C SGND OSC SYNC OSC – + 0.74V LTC1735F ONLY OV + – 0.86V V OSENSE V gm =1.3m FB – 0. 0.86V SD RUN 1.2 A ...
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LTC1735 U OPERATIO (Refer to Functional Diagram) The main control loop is shut down by pulling Pin 2 (RUN/SS) low. Releasing RUN/SS allows an internal 1.2 A current source to charge soft-start capacitor C C reaches 1.5V, the main control ...
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U OPERATIO (Refer to Functional Diagram) INTV /EXTV POWER CC CC Power for the top and bottom MOSFET drivers and most of the internal circuitry of the LTC1735 is derived from the INTV pin. When the EXTV pin is left ...
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LTC1735 U U APPLICATIO S I FOR ATIO The internal oscillator runs at its nominal frequency (f when the FCB pin is pulled high to INTV ground. Clocking the FCB pin above and below 0.8V will cause the internal oscillator ...
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U U APPLICATIO S I FOR ATIO Ferrite designs have very low core loss and are preferred at high switching frequencies, so design goals can con- centrate on copper loss and preventing saturation. Ferrite core material saturates “hard,” which means ...
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LTC1735 U U APPLICATIO S I FOR ATIO C Selection IN In continuous mode, the source current of the top N-channel MOSFET is a square wave of duty cycle prevent large voltage transients, a low ESR ...
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U U APPLICATIO S I FOR ATIO capacitor available from Sanyo has the lowest (ESR)(size) product of any aluminum electrolytic at a somewhat higher price. An additional ceramic capacitor in parallel with OS-CON capacitors is recommended to reduce the inductance ...
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LTC1735 U U APPLICATIO S I FOR ATIO derived from the output or other external source during normal operation. When the output is out of regulation (start-up, short circuit) power is supplied from the internal regulator. Do not apply greater ...
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U U APPLICATIO S I FOR ATIO V OSENSE 47pF LTC1735 SGND 1735 F04 Figure 4. Setting the LTC1735 Output Voltage Topside MOSFET Driver Supply (C An external bootstrap capacitor C BOOST pin supplies the gate drive voltage for the ...
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LTC1735 U U APPLICATIO S I FOR ATIO Diode D1 in Figure 5 reduces the start delay while allowing C to charge up slowly for the soft-start function. This SS diode and C can be deleted if soft-start is not ...
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U U APPLICATIO S I FOR ATIO t of the LTC1735 (approximately 200ns), the input ON(MIN) voltage and inductor value L(SC) ON(MIN) IN The resulting short-circuit current is ...
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LTC1735 U U APPLICATIO S I FOR ATIO FCB Pin Operation When the FCB pin drops below its 0.8V threshold, continu- ous mode operation is forced. In this case, the top and bottom MOSFETs continue to be driven synchronously regardless ...
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U U APPLICATIO S I FOR ATIO Although all dissipative elements in the circuit produce losses, 4 main sources usually account for most of the losses in LTC1735 circuits current losses, 4) Topside ...
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LTC1735 U U APPLICATIO S I FOR ATIO The I series R –C filter sets the dominant pole-zero loop compensation. The values can be modified slightly (from 0 times their suggested values) to optimize transient ...
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... C9, C19: TAIYO YUDEN JMK107BJ105 C10: KEMET T494A475M010AS C12 TO C14: TAIYO YUDEN GMK325F106 16 M1 C15 TO C18: PANASONIC EEFUE0G181R FDS6680A D1: CENTRAL SEMI CMDSH-3 D2: MOTOROLA MBRS340 15 L1: PANASONIC ETQP6F1R0SA M1 TO M3: FAIRCHILD FDS6680A C8 R5: IRC LRF2512-01-R003-J 0. U1: LINEAR TECHNOLOGY LTC1735CS 13 D1 CMDSH MBRS340 M2 FDS6680A + C10 ...
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LTC1735 U U APPLICATIO S I FOR ATIO At full load current • . ITH MAX ( ) minimum load current ...
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U U APPLICATIO S I FOR ATIO V = 12V FIGURE 8 CIRCUIT IN OUTPUT V = 1.5V OUT VOLTAGE 1.5V 100mV/DIV 15A LOAD 10A/DIV CURRENT 0A 50 s/DIV Figure 9. Normal Transient Response (Without R1, R4 12V ...
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LTC1735 U U APPLICATIO S I FOR ATIO Next verify the minimum on-time of 200ns is not violated. The minimum on-time occurs at maximum OUT t ON MIN ( ) 300 V ...
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U U APPLICATIO S I FOR ATIO the INTV and PGND pins can help improve noise CC performance. 6) Keep the switching node (SW), top gate node (TG) and boost node (BOOST) away from sensitive small-signal nodes, especially from the ...
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LTC1735 U TYPICAL APPLICATIO S 1.8V/5A Converter from Design Example with Burst Mode Operation Disabled C OSC 43pF 1 C OSC RUN/ 470pF 33k 220pF 4 ...
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U TYPICAL APPLICATIO S Selectable Output Voltage Converter with Burst Mode Operation Disabled for CPU Power OSC 43pF 2 C OSC RUN/ 330pF 33k ...
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LTC1735 U TYPICAL APPLICATIO S C OSC 51pF 1 C OSC RUN/ 470pF 33k LTC1735 220pF 4 FCB 5 SGND 100pF 6 V OSENSE 7 SENSE ...
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... DIMENSIONS IN (MILLIMETERS) 2. DRAWING NOT TO SCALE 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 Package 20-Lead Plastic TSSOP (4 ...
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... Current Mode Synchronous Step-Down SENSE Controller LTC3832 Low V High Power Synchronous Controller IN LTC4008 4A Multichemistry Multicell Battery Charger trademark of Linear Technology Corporation. Pentium is a registered trademark of Intel Corporation. SENSE Linear Technology Corporation 32 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 3.3V ...