sp6641b Exar Corporation, sp6641b Datasheet
sp6641b
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sp6641b Summary of contents
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... R1 C2 SP6641A 3.3V & 5V 22µF Ceramic 22µH CDRH5D28 MBR0520 Open Shorted. SP6641B 3.3V & 5V 100µF POSCAP 10µH CDRH5D28 ZHCS2000 1µF Ceramic 10Ω. Figure 1. Typical Application Schematic Rev. 5/26/05, *Patent Pending SP6641A/6641B 500mA Alkaline DC/DC Boost Regulator in SOT-23 ...
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... BATT I SHDN Inductor Current Limit (SP6641A) Inductor Current Limit (SP6641B) Output Current (SP6641AEK-3.3) Output Current (SP6641BEK-3.3) Output Current (SP6641AEK-5.0) Output Current (SP6641BEK-5.0) Minimum Off-Time Constant K OFF NMOS Switch Resistance SHDN Input Voltage Vil Vih SHDN Input Current Rev. 5/26/05, *Patent Pending SP6641A/6641B 500mA Alkaline DC/DC Boost Regulator in SOT-23 ...
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... Output voltage sense pin, internal regulator voltage supply, and minimum off-time one shot input. Kelvin connect this pin to the positive terminal of the output capacitor, but for SP6641B, use 10Ω series resistor and 1µF bypass per Figure 1 schematic. Shutdown. Tie this pin to V for normal operation ...
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... Iload (mA) Figure 7. SP6641AEK-5.0 Efficiency Vs Load Current Rev. 5/26/05, *Patent Pending SP6641A/6641B 500mA Alkaline DC/DC Boost Regulator in SOT-23 100 100.0 1000.0 0.1 Figure 4. SP6641BEK - 3.3 Efficiency vs Load Current 3.400 V = 1.3V 3.380 1.0V IN 3.360 3.340 3.320 3.300 3.280 3.260 3.240 3.220 3.200 200 250 0 Figure 6 ...
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... Figure 10. SP6641BEK-5.0 Line/Load Rejection Vs Load Current 500 450 400 350 300 250 200 150 100 50 0 0.5 1.0 3.5 4.0 4.5 Figure 12. SP6641BEK-3.3 & SP6641AEK-5.0 No Load Battery Current 700 600 500 400 300 200 100 0 3.5 4.0 4.5 0.5 1.0 Figure 14. SP6641BEK-3.3 & SP6641BEK-5.0 Maximum Resistive Load Current in Startup 5 Vi=4.2V Vi=3.6V Vi=3 ...
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... SOT23 5 pin package, and precise inductor peak current control. SP6641A sources up to 90mA at 1.3V, typ. and SP6641B sources up to 500mA at 2.6V, typ. by supporting different peak inductor current levels. Only two capacitors, an inductor, and a diode are required to build a power supply for the SP6641A ...
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OPERATION Loop Regulation: continued The SP6641 feed forward off-time control de- livers more load current than constant off-time control because the input battery voltage drops during its life cycle. The term (I the average current delivered to the output ca- ...
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... The SP6641B evaluation board uses a Sumida CDRH5D28 10µH inductor with an Isat value of 1.3A and a DCR of 0.065Ω, which easily handles the Ipeak of 1.0A of the SP6641B and will deliver high efficiencies. Other inductors could be selected provided their Isat is greater than the Ipeak of the SP6641A/SP6641B. ...
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... SP6641A Ipk = .33A STMicro STPS0520Z SP6641B Ipk = 1A Zetex ZCHS2000 Note: Components highlighted in bold are those used on the SP6641A or SP6641B Evaluation Board. Rev. 5/26/05, *Patent Pending SP6641A/6641B 500mA Alkaline DC/DC Boost Regulator in SOT-23 From the curves in Figures 13 and 14, you can see that for low input voltages, the 22µH induc- tor has more current capacity at startup than the 10µ ...
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APPLICATION INFORMATION: continued +0.9V to +3.3V Input V BATT L1 22µ SP6641 2 D1 GND 3 SHDN V OUT + C2 22µF Figure 15. SP6641A 3.3V Evaluation Board with SP6201 LDO Regulator SuperCap Application on the SP6641 ...
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APPLICATION INFORMATION: continued Low Battery Circuit for SP6641 Application The circuit in figure 17 uses the Sipex SPX432 shunt regulator as a reference and comparator circuit to detect a low battery condition and give a high level, typically 1.7V output. ...
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Rev. 5/26/05, *Patent Pending SP6641A/6641B 500mA Alkaline DC/DC Boost Regulator in SOT-23 PACKAGE: 5 Lead SOT23 .10 SYMBOL MIN MAX ...
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... SP6641BEK-3.3/TR ............. L1 ...................... -40°C to 85°C ........ (Tape & Reel) 5-Pin SOT-23 SP6641AEK-5.0/TR ............. P1 ...................... -40°C to 85°C ........ (Tape & Reel) 5-Pin SOT-23 SP6641BEK-5.0/TR ............. Q1 ...................... -40°C to 85°C ........ (Tape & Reel) 5-Pin SOT-23 Available in lead free packaging. To order add “-L” suffix to part number. ...