SC453 Semtech Corporation, SC453 Datasheet
SC453
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SC453 Summary of contents
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... POWER MANAGEMENT Description The SC453 single chip high-performance Hysteretic PWM controller. With its integrated SmartDriver™, it pow- ers advanced graphics and core processors. It provides sleep mode and boot voltage support. Automatic "power- save" is present to prevent negative current flow in the low-side FET during light loading conditions saving even more power ...
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... POWER MANAGEMENT Reference Design www.DataSheet4U.com 1 1 © 2006 Semtech Corp www.semtech.com SC453 ...
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... EN is high in UVLO 3 Conditions Min Max -0.3 7 -0.3 V +0.3 CCA 7 Static -0 -0.3 7 Static - BST -2 +0.3 -0.3 0.3 TSSOP-28 70 TSSOP-28 20 TSSOP-28 300 TSSOP-28 260 Min Typ Max 3.0 4.3 5.0 4.5 5.0 400 www.semtech.com SC453 Units °C/W °C/W °C °C Units 25 V 6 μA μA ...
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... UVLO condition Measured from PG# assertion 4 Min Typ 5 3.47 3.70 190 3.85 4.00 210 1.95 2.00 2 1.1× V DAC 0.86× V DAC DAC < 0.88*V , 0.95× DAC > 1.12*V V DAC PULL-UP 0.95× V PULL-UP 0.95× V PULL-UP , DAC 1007 SC453 Max Units 0.8 V 1.15× V DAC V 0.9× V DAC % 0 0.4 0.8 Clocks www.semtech.com ...
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... CMP V REFIN 5 Min Typ 5 10 < 85°C, 7.5 10.5 A 204 256 < 85°C 180 240 < 85°C 102 128 A < 85°C 90 120 A 40 0.55 -0.85 -2 |±1.5| SC453 Max Units mA 16 310 μA 320 155 160 100 mV V 0.45 +0.85 % +2.0 % |±3| % μs |± 0.8 |±2| μA |±3| mV www.semtech.com ...
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... CL CLRF > CLRF < V 120 150 CL CLRF > V 195 230 CL CLRF 1.5 < 1V 4.2 DRN > DRN = 5V 0 SC453 Max Units -90 110 μA -13 13 -63 μA 83 |±2| μA |±5| mV 250 350 μ 180 μA 265 |± Ω 4 1.4 Ω ...
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... C = 3nF CMP crossing REFIN to 10% tpdh point of BG 3nF, DRN = CMP crossing REFIN to 90% tpdl point of TG 3nF, DRN = Min Typ 1.0 0 SC453 Max Units 2.6 Ω 1 www.semtech.com ...
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... Core Comparator Hysteresis. Connect to ground thru an external resistor called R Hysteresis current is established by an internal V VID most signifi cant bit main controller voltage programming DAC input. VID input. 8 Device Package Temp Range(T TSSOP-28 -40° 125°C EVALUATION BOARD voltage, 1.7V, divided by R REF SC453 ) J . HYS . HYS www.semtech.com ...
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... Current limit input pin. Enable - active high. This is capable of accepting a 5.0V signal level. Power ground. Connect to the synchronous FET power ground. Output drive for the synchronous (low-side) FET. 5VDC supply for the driver. A capacitor should be connected from V5 to GND. 9 SC453 period has terminated. CPU_PWRGD www.semtech.com ...
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... POWER MANAGEMENT Block Diagram ` www.DataSheet4U.com ` SLPV BOOTV SLP PG# PG_DEL © 2006 Semtech Corp. ``` VID/SLPV Sleep Mode Detect 10 SC453 REFIN www.semtech.com ...
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... Over-Voltage Protection If the CORE voltage is greater than +14% of the DAC (i.e., out of the power good window), the SC453 will latch off and hold the low-side driver on permanently. Either the power or EN must be recycled to clear the latch. The latch is disabled during soft-start and VID/Sleep transitions ...
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... In this mode, the voltage applied to the SLPV pin appears at the DAC output when SLP is asserted. By holding the SLPV pin at VCCA during start-up, "VID con- trolled sleep" mode is engaged. In this mode, the DAC out- put continues to be set by the VID inputs even when SLP is asserted. 12 SC453 www.semtech.com ...
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... Applications Information (Cont.) PG# Output This is an open-drain output and should be pulled up ex- ternally. This signal is asserted (pulled low) by the SC453 whenever the core voltage is within ±14% of the VID programmed value. If the chip is disabled or enabled in UVLO, then PG# is de-asserted. During start-up PG# re- mains de-asserted until the core voltage has reached the defi ...
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... RIPPLE © 2006 Semtech Corp. Step 2: Output Inductor and Capacitor Selection The SC453 has "passive" droop. The voltage at full load is less than the DAC voltage by the voltage drop across the current sense resistor and any PCB copper losses from the sense resistor to the processor socket. The steady- ...
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... This condition applies only to the positive transient. − 7 × 0.60 μH ⋅ ⋅ − MAX_FL LKGMAX := dT − INMIN MAX_NL − × dT 1.326 − ⋅ MAX_FL LKGMAX := C MINP V POS_TRANS − × C 4.278 10 F MINP www.semtech.com SC453 ) − 7 ⋅ ⋅ sec ...
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... ⎝ ⎠ − CAP L LKGMAX R ESR ( ) , := ⋅ ESR CAP CAP N CAP ⋅ I CAP ( ) , := CAP CAP ⋅ OUT CAP ( ) ( ) , := , + TOTAL CAP ESR CAP CAP www.semtech.com SC453 ( ) , t N CAP ...
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... R7 (the resistor in series with the CMP pin) fi rst, and then calculate the SC453 application circuit, R sistors (R3, R4 and R5). These resistors also form the dividers for BOOTV and SLPV. Note also that depending on circuit layout and parasitics Since the SC453 is a HYS justed slightly to obtain optimum performance ...
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... V SLP − ⎝ REF SLP © 2006 Semtech Corp. is set at 1.2V. For the SC453 soln From the standard 1% resistor value table, we choose the following values according to the calculation results 33.2KΩ 30.1KΩ ...
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... CLIM PEAK = I 28.066 A CLIM The Current Limit Comparator internal to the SC453 moni- tors the output current and turns the high side switch off when the current exceeds the upper current limit thresh- old, I and re-enables only if the load current drops be- CLMAX ...
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... Step 9: OVP No calculations are necessary for Over-Voltage Protection power good window), the SC453 will latch off and hold the low-side driver on permanently (for each phase). Either the power or EN must be recycled to clear the latch. The latch is disabled during soft-start and VID/DeeperSleep transitions ...
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... MAX_NL ⋅ I SSS := C SS_max_drs dV dacS = C 1.714 SS_max_drs Exercise #1 predicts the max capacitance allowed. In order to allow tolerance, we choose C22 = 15nF. © 2006 Semtech Corp. ⋅ dacSU − 8 × MIN_NL dt V − 8 × SLP dt S − 8 × SC453 www.semtech.com ...
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... E D .378 .382 .386 9.60 9.70 9.80 E1 .169 .173 .177 4.30 4.40 4.50 E .252 BSC 6.40 BSC e .026 BSC 0.65 BSC L .018 .024 .030 0.45 0.60 0.75 L1 (.039) (1. 0° 8° 0° 8° aaa .004 0.10 bbb .004 0.10 ccc .008 0. GAGE PLANE 0. (L1 DETAIL -H- SC453 www.semtech.com ...
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... THIS LAND PATTERN IS FOR REFERENCE PURPOSES ONLY. CONSULT YOUR MANUFACTURING GROUP TO ENSURE YOUR COMPANY'S MANUFACTURING GUIDELINES ARE MET. Semtech Corporation Power Management Products Division 200 Flynn Road, Camarillo, CA 93012 Phone: (805) 498-2111 Fax: (805) 498-3804 www.semtech.com 23 DIMENSIONS INCHES MILLIMETERS (.222) (5.65) .161 4.10 .026 0.65 .016 0.40 .061 1.55 .283 7.20 www.semtech.com SC453 ...