sc2544 Semtech Corporation, sc2544 Datasheet
sc2544
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sc2544 Summary of contents
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... POWER MANAGEMENT Description The SC2544 is a high performance dual PWM controller designed to convert a wide ranged input voltage down to two independent output rails. The PWM operations of the two channels are 180 degree out of phase which can greatly reduce the size and the cost of the input capacitors ...
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... SC2544 ...
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... SC2544 ...
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... Lead free package. Device is fully WEEE and RoHS compiant. FB2 FB2 19 19 ERROUT2 ERROUT2 SS2 SS2 ERROUT1 ERROUT1 ILIM2 ILIM2 BST2 BST2 DRVH2 DRVH2 13 13 DRVH1 DRVH1 PHASE1 PHASE1 DRVL1 DRVL1 PGND PGND 4 SC2544 ...
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... POWER MANAGEMENT Pin Descriptions for SC2544TSTRT (TSSOP ...
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... POWER MANAGEMENT Pin Descriptions for SC2544MLTRT (MLPQ ...
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... Semtech Corp. PWM 0.75V + OUT R - Protect UVLO 0.75V Band 10V Band Gap 1 LDO Gap 2 0.75V 0.675V FB1 FB2 7 SC2544 PVCC Protect 1 PHASE1 PVCC Protect 1 VCC 10u A - OCP OUT + FB1 + OVP OUT - 0.89V + - OUT OVP OCP - www.semtech.com BST1 DRVH1 ...
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... DRVH/ DRVL signals stop pulsing. The output voltage ramps down at a rate determined by the load condition. The SC2544 can also be shutdown by pulling down directly on the SS pin. The designer needs to consider the slope of the SS pin voltage and choose a suitable pull down resistor to prevent the output from undershooting ...
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... External pull up is re- quired for the PWRGD pin, and the pull up resistor should be chosen such that the pin does not sink more than 2mA when PWRGD is low. 9 SC2544 100n S 100n ctive ctive B lan kin g ...
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... Inductor (L) and Ripple Current Inductor (L) and Ripple Current Inductor (L) and Ripple Current Inductor (L) and Ripple Current Both step-down controllers in the SC2544 operate in synchronous continuous-conduction mode (CCM) regardless of the output load level. The output inductor selection/design is based on the output DC and transient requirements. Both output current and ...
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... & & ( ( ¢ ¢ ã HVO HVU P & & & & SC2544 & & & & & & & ...
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... 5D 5 5LQ 5HVU ' &LQ 9'& ã & & & & & & & & &LQ &LQ 5HT HVU HVU &LQ &LQ / &R 5R SC2544 & & ...
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... The two step-down channels of the SC2544 operate at 180 degrees from each other. If both step- down channels in the SC2544 are connected to the same input rail, the input RMS currents will be reduced. Ripple cancellation effect of interleaving allows the use of smaller input capacitors ...
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... Switching loss however increases with the input voltage. The total power loss of MOSFET should be calculated and compared for high-line and low-line cases. The worst case is then used for thermal design. 14 SC2544 is the gate charge needed to bring gs1 to the threshold voltage gs is falling. ...
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... The block diagram in Figure 10 represents the control . loop of a buck converter designed with the SC2544. The control loop consists of a compensator, a PWM modula- tor, and an LC filter. The LC filter and PWM modulator represent the small signal model of the buck converter operating at fixed switching frequency ...
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... Place the second compensator zero Fz2 at or below the power stage resonant frequency Fo. A MathCAD program is available upon request for the calculation of the compensation parameters Rtop Rbot 16 SC2544 of the divider in Fig. 12 top to 30k . Then the bot- is found from: bot . ...
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... Stage er Stage 1) Separate the power ground from the signal ground. In SC2544 design, use an isolated local ground plane for the controller and tie it to power grand. 2) Minimize the size of the high pulse current loop. Keep the top MOSFET, the bottom MOSFET and the input capacitors within a small area with short and wide traces ...
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... PHASE1 PHASE2 11 14 DRVL1 DRVL2 VCC VIN PGND PVCC C31 C8 R24 Q2 0R 7.6uH Q3 C34 N.P. C30 N.P. R25 N.P. Vin: 4.5V ~ 28V Vout: 3.3V/6A and 5V/6A 18 SC2544 VO2 R2 10K 73.2K PWGRD FB2 SS2 1n C4 C12 4.7n C11 R5 18k R7 4.7K C33 N.P. R11 2.2 VIN+ C13 C14 C15 C16 Q1 0.1uF/25V 10uF/25V 10uF/25V N ...
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... SC2544 ...
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... Shut down by pulling down EN pin CH1: EN CH1: EN CH2: VO1 CH2: VO1 CH3: VO2 CH3: VO2 Transient response(0-5A). CH1: EN CH1: EN CH2: VO1 CH2: VO1 CH3: VO2 CH3: VO2 Over current protection (5A/10mV) 20 SC2544 CH1:Vi CH2:Ven CH3:VSS CH4:Vo voltage. CH3:Vo CH4:Io CH1:TG CH2:BG CH3:TG CH4:BG www.semtech.com ...
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... Semtech Corp. Vin=16V 190 188 186 184 182 180 178 10.5 10.3 10.1 9.9 9.7 9 10.13 10.11 10.09 10.07 10.05 10.03 -40 21 SC2544 -40 - 110 Temperature (Degree C) Freq. vs. Temp. ( Rosc=75kohm, Vin=16V). Vin (V) Vcc vs. Vin ( Ta=25 Degree C). - 100 Tj (Degree C) Vcc vs. Temp. www.semtech.com 120 ...
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... Tj (Degree C) DL min Ton vs. Tj (Vin=16V). 100 -40 - (Degree C) Dead time vs. Tj (Vin=16V, DH falling to DL rising). 2005 Semtech Corp 100 120 60 80 100 120 22 SC2544 www.semtech.com ...
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... BSC 6.40 BSC .026 BSC 0.65 BSC .024 .030 0.45 0.60 0.75 (.039) (1. 0° 8° 0° 8° .004 0.10 .004 0.10 .008 0. (L1) A DETAIL DIMENSIONS MILLIMETERS (.222) (5.65) .161 4.10 .026 0.65 .016 0.40 .061 1.55 .283 7.20 www.semtech.com SC2544 ...
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... D/2 K DIM Semtech Corporation Power Management Products Division 200 Flynn Road, Camarillo, CA 93012 Phone: (805)498-2111 FAX (805)498-3804 24 SC2544 DIMENSIONS INCHES MILLIMETERS MIN NOM MAX MIN NOM MAX .031 .035 .040 0.80 0.90 1.00 0.02 .000 .001 .002 0.00 0.05 - ...