LTC3736EUF#TR Linear Technology, LTC3736EUF#TR Datasheet
LTC3736EUF#TR
Specifications of LTC3736EUF#TR
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LTC3736EUF#TR Summary of contents
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... The LTC3736 is available in the tiny thermally enhanced (4mm × 4mm) QFN package or 24-lead SSOP narrow package. , LTC and LT are registered trademarks of Linear Technology Corporation. Burst Mode is a registered trademark of Linear Technology Corporation Linear Technology Corporation. All other trademarks are the property of their respective owners ...
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LTC3736 ABSOLUTE AXI U RATI GS Input Supply Voltage (V ) ........................ – 0.3V to 10V IN PLLLPF, RUN/SS, SYNC/FCB TRACK, SENSE1 , SENSE2 , IPRG1, IPRG2 Voltages ................. – 0. ...
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ELECTRICAL CHARACTERISTICS range, otherwise specifications are at T PARAMETER Output Voltage Load Regulation V Input Current FB1,2 TRACK Input Current Overvoltage Protect Threshold Overvoltage Protect Hysteresis Auxiliary Feedback Threshold Top Gate (TG) Drive 1, 2 Rise Time Top Gate (TG) ...
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LTC3736 W U TYPICAL PERFOR A CE CHARACTERISTICS Efficiency and Power Loss vs Load Current 100 FIGURE 15 CIRCUIT 3.3V OUT 2.5V OUT V = 1.8V 60 OUT V ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS Maximum Current Sense Voltage vs I Pin Voltage TH 100 Burst Mode OPERATION (I RISING Burst Mode OPERATION (I FALLING) TH FORCED CONTINUOUS 60 MODE PULSE SKIPPING MODE ...
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LTC3736 W U TYPICAL PERFOR A CE CHARACTERISTICS Shutdown Quiescent Current vs Input Voltage 20 RUN/ INPUT VOLTAGE ( ...
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CTIO S (UF/GN Package) For auxiliary winding applications, connect to a resistor divider from the auxiliary output. To synchronize with an external clock using the PLL, apply a CMOS compatible clock with a frequency between ...
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LTC3736 CTIO AL DIAGRA CLK1 – ICMP + IPROG1 BURSTDIS 0.3V SLEEP1 OV1 8 W (Controller 1) RS1 SWITCHING LOGIC ANTISHOOT AND THROUGH OV1 BLANKING CIRCUIT SC1 FCB SLEEP1 IREV1 SLOPE1 SW1 + SENSE1 ...
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CTIO AL DIAGRA CLK2 – ICMP + BURSTDIS 0.3V SLEEP2 OV2 W (Controller 2) RS2 SWITCHING LOGIC ANTISHOOT AND THROUGH OV2 BLANKING SC2 CIRCUIT FCB SLEEP2 IREV2 SLOPE2 SW2 + SENSE2 + – – ...
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LTC3736 U OPERATIO (Refer to Functional Diagram) Main Control Loop The LTC3736 uses a constant frequency, current mode architecture with the two controllers operating 180 de- grees out of phase. During normal operation, the top external P-channel power MOSFET is ...
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U OPERATIO (Refer to Functional Diagram) When a controller is enabled for Burst Mode operation, the inductor current is not allowed to reverse. Hence, the controller operates discontinuously. The reverse current comparator (RICMP) senses the drain-to-source voltage of the bottom ...
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LTC3736 U OPERATIO (Refer to Functional Diagram) Dropout Operation When the input supply voltage (V IN the output voltage, the rate of change of the inductor current while the external P-channel MOSFET is on (ON cycle) decreases. This reduction means ...
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U OPERATIO (Refer to Functional Diagram) With 2-phase operation, the two controllers of the LTC3736 are operated 180 degrees out of phase. This effectively interleaves the current pulses coming from the topside MOSFET switches, greatly reducing the time where they ...
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LTC3736 U U APPLICATIO S I FOR ATIO The typical LTC3736 application circuit is shown in Fig- ure 13. External component selection for each of the LTC3736’s controllers is driven by the load requirement and begins with the selection of ...
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U U APPLICATIO S I FOR ATIO 2.0 1.5 1.0 0.5 0 – JUNCTION TEMPERATURE (°C) Figure Temperature DS(ON) The MOSFET power dissipations at maximum output current are OUT P • I ...
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LTC3736 U U APPLICATIO S I FOR ATIO operation improves efficiency by reducing MOSFET switch- ing losses, both gate charge loss and transition loss. However, lower frequency operation requires more induc- tance for a given amount of ripple current. The ...
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U U APPLICATIO S I FOR ATIO than ferrite. A reasonable compromise from the same manufacturer is Kool Mµ. Toroids are very space efficient, especially when you can use several layers of wire. Because they lack a bobbin, mounting is ...
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LTC3736 U U APPLICATIO S I FOR ATIO where f is the operating frequency, C capacitance and I is the ripple current in the induc- RIPPLE tor. The output ripple is highest at maximum input voltage since I increases with ...
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U U APPLICATIO S I FOR ATIO TIME (7b) Coincident Tracking Figures 7b and 7c. Two Different Modes of Output Voltage Tracking For coincident tracking ( OUT1 OUT2 R2A = R TRACKA R2B = R TRACKB The ramp ...
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LTC3736 U U APPLICATIO S I FOR ATIO SYNC/ FCB EXTERNAL OSCILLATOR If the external clock frequency is greater than the internal oscillator’s frequency then current is sourced con- OSC tinuously from the phase detector output, pulling up ...
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U U APPLICATIO S I FOR ATIO V IN LTC3736 L1 1 SYNC/FCB Figure 10. Auxiliary Output Loop Connection If V drops below this value, the FCB voltage forces AUX temporary continuous switching operation until ...
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LTC3736 U U APPLICATIO S I FOR ATIO continuous mode is selected and the duty cycle falls below the minimum on-time requirement, the output will be regu- lated by overvoltage protection. Efficiency Considerations The efficiency of a switching regulator is ...
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U U APPLICATIO S I FOR ATIO deliver enough current to prevent this problem if the load switch resistance is low and it is driven quickly. The only solution is to limit the rise time of the switch drive so ...
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LTC3736 U U APPLICATIO S I FOR ATIO BOLD LINES INDICATE HIGH, SWITCHING CURRENT LINES. KEEP LINES TO A MINIMUM LENGTH U TYPICAL APPLICATIO S R FB1A 59k C ITH1A 100pF C ITH1 ...
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U TYPICAL APPLICATIO S R FB1A 59k C ITH1A 100pF R ITH1 C ITH1 22k 470pF V IN 3.3V R 10Ω VIN C IN 22µF C ITH2 C 470pF VIN 1µ 10nF ITH2A 100pF R FB2A 59k ...
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LTC3736 U TYPICAL APPLICATIO 2-Phase, 550kHz, Dual Output Synchronous DC/DC Converter with Different Power Stage Input Supplies R FB1A 59k C ITH1A 100pF R ITH1 C ITH1 15k 220pF V IN1 5V R 10Ω VIN C IN 10µF ×2 C ...
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... FLASH SHALL NOT EXCEED 0.010" (0.254mm) 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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... SENSE Output Tracking LTC3776 Dual, 2-Phase SENSE Memory Termination LTC3808 Low EMI, Synchronous Step-Down Controller with SENSE Output Tracking trademark of Linear Technology Corporation. SENSE Linear Technology Corporation 28 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● FB1B MP1 22 21 ...