LTC3736EUF Linear Technology, LTC3736EUF Datasheet
LTC3736EUF
Specifications of LTC3736EUF
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LTC3736EUF 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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... Operating Temperature Range (Note 2) ... –40°C to 85°C Storage Temperature Range .................. –65°C to 125°C + 0.3V) Junction Temperature (Note 3) ............................ 125°C IN Lead Temperature (Soldering, 10 sec 10V Max (LTC3736EGN) ..................................................... 300° ORDER PART NUMBER SW1 LTC3736EUF IPRG1 V FB1 I TH1 IPRG2 PLLLPF SGND PART MARKING TRACK V ...
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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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... MP1 SW1 SENSE1 23 20 IPRG1 PGND BG1 FB1 SYNC/FCB TH1 ITH1 IPRG2 TG1 3 16 15k PLLLPF PGND 4 15 SGND TG2 R 10Ω LTC3736EUF VIN RUN/ BG2 ITH2 PGND PGOOD 220pF SENSE2 FB2 8 MP2 I TH2 ITH2 TRACK SW2 15k PGND 25 C ITH2B ...
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... R FB1B 187k MP1 Si3447BDV SW1 SENSE1 23 20 IPRG1 PGND BG1 FB1 SYNC/FCB TH1 2 17 IPRG2 TG1 3 16 PLLLPF PGND 4 15 SGND TG2 LTC3736EUF RUN/ BG2 9 12 PGND PGOOD SENSE2 FB2 8 MP2 I TH2 6 10 Si3447BDV R ITH2 TRACK SW2 22k PGND FB2B TRACKA ...
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... R FB1B 187k MP1 SW1 SENSE1 23 20 IPRG1 PGND BG1 FB1 SYNC/FCB TH1 2 17 IPRG2 TG1 3 16 PLLLPF PGND 4 15 SGND TG2 LTC3736EUF RUN/ BG2 9 12 PGND PGOOD SENSE2 FB2 8 MP2 I TH2 ITH2 TRACK SW2 15k PGND FB2B TRACKA TRACKB ...
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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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... MP1 SW1 SENSE1 23 20 IPRG1 PGND 24 19 MN1 V BG1 FB1 1 18 Si7540DP I SYNC/FCB TH1 2 17 IPRG2 TG1 3 16 PLLLPF PGND 4 15 SGND TG2 LTC3736EUF RUN/ MN2 BG2 9 12 Si7540DP PGND PGOOD SENSE2 FB2 8 MP2 I TH2 6 10 TRACK SW2 PGND SANYO 4TPB150MC ...