SC4501 Semtech Corporation, SC4501 Datasheet
SC4501
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SC4501 Summary of contents
Page 1
... Boost, SEPIC and Flyback. www.DataSheet4U.com The operating frequency of the SC4501 can be set with an external resistor. The ability to set the operating frequency gives the SC4501 design flexibilities. A dedicated COMP pin allows optimization of the loop response. The SC4501 is available in thermally enhanced 8-Pin MSOP and 10-pin MLPD packages ...
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... 160 J -65 to +150 260 2000 Min Typ Max 1.3 1.4 16 1.224 1.242 1.260 1.217 1.267 0. 1.1 1 1.3 1.5 1 2.8 220 350 SC4501 Units °C °C/W °C °C °C V Unit MHz www.semtech.com ...
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... RoHS compliant. (3) Contact factory for availability ROSC Min Typ 0.01 1.02 1.1 -4.6 0 1.5 160 10 (1)(2) Device Package Temp. Range( T MLPD-10 (3) MSOP-8-EDP Evaluation Board Lead free product. This product is fully WEEE and SC4501 Max Unit °C ° -40 to 85°C www.semtech.com ...
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... CMP - 1.1V VOLTAGE REFERENCE 1.242V FB 2 COMP REG_GOOD ENABLE ROSC 7 2005 Semtech Corp. INTERNAL SUPPLY ENABLE THERMAL SHUTDOW N CLK + - EA - PWM REG + 1.5 A CLK OSCILLATOR Figure 2. SC4501 (MSOP-8) Block Diagram. 4 SC4501 SW 5 REG I-LIMIT ILIM - R SENSE + + ISEN - + SLOP E COMP 4 GND www.semtech.com ...
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... REFERENC E 1.242V FB 2 COMP REG_GOOD ENABL E ROSC 9 2005 Semtech Corp. INTERNAL SUPPLY ENABL E THERMAL SHUTDOWN CLK + - EA - PWM REG + 1.5 A CLK OSCILLATOR Figure 3. SC4501 (MLPD-10) Block Diagram. 5 SC4501 REG I-LIMIT ILIM - R SENSE + + ISEN - + SLOPE COMP 4 5 GND GND www.semtech.com ...
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... 1.4 1.3 2.0 2.5 3.0 -50 - Temperature (ºC) Minimum V IN 1.5 1.4 1.3 1.2 1 100 -50 - Temperature (ºC) Shutdown Threshold vs Temperature 1.20 1.15 125ºC 1.10 1. SHDN 1. -50 - Temperature (ºC) SC4501 R = 7.68K OSC 50 75 100 125 vs Temperature 50 75 100 125 100 125 www.semtech.com ...
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... SHDN Voltage (V) Transconductance vs Temperature -50 - 100 125 Temperature (ºC) 7 Shutdown Pin Current vs Temperature - 25º 0.8 1 1.2 -50 -25 0 Temperature (º 100 125 SC4501 V = 1.25V SHDN 12V 100 125 www.semtech.com ...
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... The SC4501 requires a minimum input of 1.4V to operate. A voltage higher than 1.1V at the shutdown pin enables the internal linear regulator REG in the SC4501. After V becomes valid, the soft-start capacitor is charged with a 1 ...
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... D)T (Figure 5). The output current available from a boost converter therefore depends on the converter operating duty cycle. The power switch current in the SC4501 is internally limited to 2A. This is also the maximum inductor or the input current. By estimating the conduction losses in both the switch and the diode, an expression of ...
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... The minimum off times of closed-loop boost converters set to various output voltages were measured by lowering their input voltages until dropout occurs. It was found that the minimum off time of the SC4501 ranged from 80 to 110ns at room temperature. Beware of dropout when operating at very low input voltages (1 ...
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... Floating the shutdown pin will result in undefined voltage. In Figure 6(c) the shutdown pin is driven from a logic gate whose V is higher than the supply voltage of the SC4501. The OH diode clamps the maximum shutdown pin voltage to one diode voltage above the input power supply. ...
Page 12
... Switching will stop if V the internal UVLO threshold. The resulting output voltage rise may be non-monotonic. The 1.1V disable threshold of the SC4501 can be used in conjunction with a resistive voltage divider to raise the UVLO threshold and to add an UVLO hysteresis. Figure 7 shows the scheme. Both V ...
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... HYS 3 2005 Semtech Corp. The turn off voltage is: V Frequency Compensation Figure 8 shows the equivalent circuit of a boost converter I HYS 4.6 A using the SC4501. The output filter capacitor and the load SWITCH CLOSED form an output pole at frequency: WHEN Y = “1” COMPARATOR where C equivalent load resistance ...
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... O Amplifier Open Loop R O Transcondu c tan GND GND SHDN SHDN SHDN VOUT VOUT Figure 9. Suggested PCB Layout for the SC4501. Notice that there is no via 2005 Semtech Corp Krads . 4 68 KHz The poles p 1 209 Krads ...
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... ROSC pin achieve a junction to ambient thermal resistance ( of 40°C/W, the exposed pad of the SC4501 should be properly soldered to a large ground plane. Use only 12mil diameter vias in the ground plane if necessary. Avoid using larger vias under the device. Molten solder may seep through large vias during reflow, resulting in poor adhesion, poor thermal conductivity and low reliability ...
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... Figure 11(b). Efficiency of the Single Li-ion Cell to 5V Boost V =2. s/div Upper Trace : Output Voltage, AC Coupled, 0.5V/div Lower Trace : Inductor Current, 0.5A/div Figure 11(c). Load Transient Response of the Circuit in Figure 11(a switched between 0.2A and 0.7A at LOAD 1A SC4501 Efficiency OUT 90 1.2MHz 4. ...
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... GND ROSC 20K 47nF R4 C4 7.68K 560pF L1 and L2: Coiltronics CTX5-1 Upper Trace : Output Voltage, AC Coupled, 0.2V/div Lower Trace : Input Inductor Current, 0.2A/div Figure 12(c). Load Transient Response of the Circuit in Figure 17 SC4501 VOUT D1 5V 10BQ015 R1 C5 60.4K 47pF 4.9 H 20K V =6V ...
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... 0 OUT1 8V (0.55A) R1 274K 49.9K D7 OUT3 -8V (10mA) C10 1 F CH4 CH1 CH2 CH3 2ms/div CH1 : OUT1 Voltage, 5V/div CH2 : OUT2 Voltage, 10V/div CH3 : OUT3 Voltage, 5V/div CH4 : SHDN Voltage, 2V/div SHDN Pin is stepped from 0 to 2V. SC4501 www.semtech.com ...
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... CH2 : FB Pin Voltage, 1V/div CH3 : LED Current, 0.5A/div CH4 : Inductor Current, 1A/div Higher LED Current (>0.7A) in Flash Mode is Possible with Fresh Battery 3. 0.1 LXCL-PWF1 R1 698 D1 10BQ015 1/2 LM358 Q1 MMBT3904T 4.7 F 0.1 F 17.4K R2 43. 10K MMBF2201NT1 TORCH FLASH V = 4.2V IN CH1 CH2 CH3 CH4 4ms/div (c) SC4501 www.semtech.com ...
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... BSC 4.90 BSC .026 BSC 0.65 BSC .068 .076 .080 1.73 1.93 2.03 .016 .024 .032 0.40 0.60 0.80 (.037) (0.95 0° 8° 0° 8° .004 0.10 .005 0.13 .010 0. (L1) A DETAIL A SEE DETAIL SIDE VIEW -H- DIMENSIONS MILLIMETERS (.161) (4.10) .081 2.08 .098 2.50 .026 0.65 .016 0.40 .063 1.60 .224 5.70 SC4501 www.semtech.com ...
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... A1 .000 .002 0.00 0.05 - (.008 (0.20 .007 .009 .011 0.18 0.23 0.30 C .074 .079 .083 1.87 2.02 2.12 D .042 .048 .052 1.06 1.21 1.31 E .114 .118 .122 2.90 3.00 3.10 e .020 BSC 0.50 BSC L .012 .016 .020 0.30 0.40 0. aaa .003 0.08 bbb .004 0.10 DIMENSIONS INCHES MILLIMETERS (.112) (2.85) .075 1.90 .055 1.40 .087 2.20 .020 0.50 .012 0.30 .037 0.95 .150 3.80 SC4501 www.semtech.com ...