LTC3736EGN-2#PBF Linear Technology, LTC3736EGN-2#PBF Datasheet
LTC3736EGN-2#PBF
Specifications of LTC3736EGN-2#PBF
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LTC3736EGN-2#PBF Summary of contents
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... QFN and 24-lead narrow SSOP packages. , LT, LTC and LTM are registered trademarks of Linear Technology Corporation trademark of Linear Technology Corporation. All other trademarks are the SENSE property of their respective owners. Protected by U.S. Patents, including 5481178, 5929620, 6144194, 6580258, 6304066, 6611131, 6498466. ...
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... TG1, TG2, BG1, BG2 Peak Output Current (<10μs) .... 1A Operating Temperature Range (Note 2) .... –40°C to 85°C + 0.3V) Storage Temperature Range ................... –65°C to 125°C IN Junction Temperature (Note 3) ............................ 125° 10V Max Lead Temperature (Soldering, 10 sec) IN (LTC3736EGN-2) ................................................... 300°C + SENSE1 PGND BG1 SYNC/FCB IPRG2 TG1 PLLLPF ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T PARAMETER Main Control Loops Input DC Supply Current Normal Mode Shutdown UVLO Undervoltage Lockout Threshold Shutdown Threshold at RUN/SS Start-Up Current Source Regulated Feedback Voltage Output Voltage Line Regulation Output ...
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LTC3736-2 ELECTRICAL CHARACTERISTICS Note 1: Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. Exposure to any Absolute Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2: The LTC3736E-2 ...
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TYPICAL PERFORMANCE CHARACTERISTICS Tracking Start-Up with External Soft-Start (C = 0.10μ OUT1 2.5V 500mV/ V OUT2 DIV 1. 40ms/DIV IN 37362 G07 1Ω LOAD1 LOAD2 FIGURE 15 CIRCUIT Effi ciency vs ...
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LTC3736-2 TYPICAL PERFORMANCE CHARACTERISTICS Undervoltage Lockout Threshold vs Temperature 2.50 2.45 V RISING IN 2.40 2.35 2.30 V FALLING IN 2.25 2.20 2.15 2.10 –60 –40 – TEMPERATURE (°C) 37362 G16 PIN FUNCTIONS (QFN/SSOP Package) ...
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PIN FUNCTIONS (QFN/SSOP Package) select. 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 compat- ible clock with a frequency between 250kHz and 850kHz. ...
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LTC3736-2 FUNCTIONAL DIAGRAM CLK1 SLOPE1 – ICMP + IPRG1 OV1 8 (Controller 1) RS1 SWITCHING LOGIC ANTISHOOT AND THROUGH OV1 BLANKING CIRCUIT SC1 FCB IREV1 SW1 + SENSE1 SHDN + EAMP – SC1 SCP + V FB1 ...
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FUNCTIONAL DIAGRAM CLK2 – ICMP + IPRG2 OV2 (Controller 2) RS2 SWITCHING LOGIC ANTISHOOT AND THROUGH OV2 BLANKING SC2 CIRCUIT FCB IREV2 SLOPE2 SW2 + SENSE2 SHDN + EAMP – SC2 SCP TRACK + V FB2 OVP ...
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LTC3736-2 OPERATION (Refer to Functional Diagram) Main Control Loop The LTC3736-2 uses a constant-frequency, current mode architecture with the two controllers operating 180 degrees out-of-phase. During normal operation, the top external P-channel power MOSFET is turned on when the clock ...
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OPERATION (Refer to Functional Diagram) higher than forced continuous mode. During start- short-circuit condition ( FB1 LTC3736-2 operates in pulse-skipping mode (no current reversal allowed), regardless of the state of the SYNC/ FCB pin. Short-Circuit Protection ...
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LTC3736-2 OPERATION (Refer to Functional Diagram) Peak Current Sense Voltage Selection and Slope Compensation (IPRG1 and IPRG2 Pins) When a controller is operating below 20% duty cycle, the peak current sense voltage (between the SENSE pins) allowed across the external ...
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OPERATION (Refer to Functional Diagram) Figure 2 shows example waveforms for a single-phase dual controller versus a 2-phase LTC3736-2 system. In this case, 2.5V and 1.8V outputs, each drawing a load current of 2A, are derived from a 7V (e.g., ...
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LTC3736-2 APPLICATIONS INFORMATION The typical LTC3736-2 application circuit is shown in Figure 13. External component selection for each of the LTC3736-2’s controllers is driven by the load requirement and begins with the selection of the inductor (L) and the power ...
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APPLICATIONS INFORMATION 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 ρ • I • TOP OUT MAX ...
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LTC3736-2 APPLICATIONS INFORMATION Operating Frequency and Synchronization The choice of operating frequency, f between effi ciency and component size. Low frequency operation improves effi ciency by reducing MOSFET switching losses, both gate charge loss and transition loss. However, lower frequency ...
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APPLICATIONS INFORMATION current requirement. Increasing the output current drawn from the other controller will actually decrease the input RMS ripple current from its maximum value. The out-of- phase technique typically reduces the input capacitor’s RMS ripple current by a factor ...
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LTC3736-2 APPLICATIONS INFORMATION V OUT R B 1/2 LTC3736 37362 F05 Figure 5. Setting Output Voltage Run/Soft-Start Function The RUN/SS pin is a dual purpose pin that provides the optional external soft-start function and a means ...
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APPLICATIONS INFORMATION TIME (7b) Coincident Tracking Figures 7b and 7c. Two Different Modes of Output Voltage Tracking For coincident tracking, V OUT • OUT F 1 where V and V ...
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LTC3736-2 APPLICATIONS INFORMATION EXTERNAL OSCILLATOR than f , current is sunk continuously, pulling down OSC the PLLLPF pin. If the external and internal frequencies are the same but exhibit a phase difference, the current sources turn on for an amount ...
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APPLICATIONS INFORMATION V IN LTC3736 1:N TG SYNC/FCB Figures 10. Auxiliary Output Loop Connection If V drops below this value, the FCB voltage forces AUX temporary continuous switching operation until V again above its minimum. ...
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... I pin waveforms that will give a sense of the overall loop s multiplied DS(ON) stability. The gain of the loop will be increased by increas- ing R , and the bandwidth of the loop will be increased C by decreasing C OPTI-LOOP is a registered trademark of Linear Technology Corporation (f) IN O(MAX) RSS ...
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... Keep the switch nodes (SW1, SW2) and the gate driver nodes (TG1, TG2, BG1, BG2) away from the small-signal components, especially the opposite channel’s feedback resistors, I rent sense pins (SENSE LTC3736 OUT1 LTC3736EGN SENSE1 SW1 2 23 PGND IPRG1 ...
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LTC3736-2 APPLICATIONS INFORMATION BOLD LINES INDICATE HIGH, SWITCHING CURRENT LINES. KEEP LINES TO A MINIMUM LENGTH 24 MP1 L1 V OUT1 + C OUT1 MN1 MP2 L2 V OUT2 + C MN2 OUT2 ...
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TYPICAL APPLICATIONS R R FB1A FB1B 59k 187k C ITH1A 100pF R ITH1 C ITH1 15k 220pF R 10Ω VIN 10μF ITH2 C 220pF VIN 2 1μF R 15k 10nF ITH2B ...
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... R 1 ITH1 24 + SW1 SENSE1 22k 2 23 IPRG1 PGND BG1 FB1 SYNC/FCB TH1 IPRG2 TG1 15k 6 19 PLLLPF PGND 18 7 TG2 SGND LTC3736EGN RUN/ BG2 12 15 PGND PGOOD SENSE2 FB2 11 MP2 I TH2 ITH2 TRACK SW2 22k FB2B TRACKA TRACKB 118k 59k 118k ...
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... DRAWING NOT TO SCALE 3. ALL DIMENSIONS ARE IN MILLIMETERS 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 representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. GN Package 24-Lead Plastic SSOP (Narrow ...
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... Dual, 2-Phase SENSE DDR/QDR Memory Termination LTC3808 Low EMI, Synchronous Step-Down Controller SENSE with Output Tracking LTC3809/LTC3809 Synchronous Step-Down Controllers SENSE trademark of Linear Technology Corporation. SENSE Linear Technology Corporation 28 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● 187k FB1B C ...