MAX1640 Maxim Integrated Products, MAX1640 Datasheet
MAX1640
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MAX1640 Summary of contents
Page 1
... Programming the off-time modifies the switching frequency, suppressing undesirable har- monics in noise-sensitive circuits. The MAX1640’s high- side current sensing allows the load to connect directly to ground, eliminating ground-potential errors. The MAX1641 incorporates a low-side current sense. ...
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... IN LOAD V = 5.5V to 26V 20mA IN LOAD MAX1640 MAX1641 MAX1640 MAX1641 0.5V to 26V IN OUT MAX1640 24V OUT MAX1641 high low (off mode low 50µA REF PFET and NFET drive R = 62kΩ TOFF D0 = low high 100kΩ ...
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... 5.5V to 26V 20mA LOAD V = 5.5V to 26V, IN LDOL 20mA LOAD MAX1640 MAX1641 MAX1640 MAX1641 24V (MAX1640) OUT high low REF 50µA REF R = 62kΩ TOFF D0 = low high 50kΩ TOFF ...
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... SWITCHING FREQUENCY vs. R TOFF 10,000 1000 V = +3V OUT 100 V = +6V OUT 100 150 200 250 300 350 400 OFF MAX1640 OUTPUT CURRENT vs. OUTPUT VOLTAGE 1.510 T = -40°C 1.500 +85°C 1.490 A 1.480 1.470 T = +25°C A 1.460 1.450 ...
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Current Source with Synchronous Rectifier ____________________________Typical Operating Characteristics (continued) (Circuit of Figure +25°C, unless otherwise noted.) A CURRENT-MODE CHANGE RESPONSE TIME A B 2ms/div V = 12V 1V OUTPUT CAPACITOR IN ...
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... Adjustable-Output, Switch-Mode Current Source with Synchronous Rectifier IN REG A1 CS+ A2 CS- B SET MUX REF A SEL TERM D0, D1 Figure 1. MAX1640/MAX1641 Functional Diagram 6 _______________________________________________________________________________________ LDOL LDOH Gm MODE CONTROL CC PDRV NDRV PGND MAX1640 MAX1641 TOFF ...
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... F Figure 2b. Standard Application Circuit part operates for 12.5% of the period set by R resulting in a lower current for pulse-trickle charging. Figure 1 is the MAX1640/MAX1641 functional diagram. Figure 2 shows the standard application circuits. ) and the voltage at The sense resistor, R levels. Choose between these two levels by holding D0 high, and toggling D1 either high or low (Table 1) ...
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... SENSE ) SENSE ) SENSE Figure 4b. Setting the Maximum Output Voltage Level The MAX1640/MAX1641 are specified for V between 0V and V increases linearly (with reduced accuracy) until it clamps at V SET Pulse-Trickle Mode: Selecting the Pulling D0 low and D1 high selects pulse-trickle mode. This current equals V on for 12 ...
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... MOSFET only (P-channel), since the Schottky rectifier or the N-FET body diode clamps the switching node before the synchronous rectifier turns on N-channel MOSFET synchronous rectifier is not used, a Schottky rectifier is needed. The MAX1640/ Synchronous Rectification MANUFACTURER Sumida CDRH125 series ...
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... Information All-Purpose Microcontroller Battery In applications where a microcontroller is available, the MAX1640/MAX1641 can be used as a low-cost battery charger (Figure 5). The controller takes over fast charge, pulse-trickle charge, charge termination, and other smart functions. By monitoring the output voltage at V ...
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... All low-current ground paths should be connected to GND. Place the input bypass capaci- tor as close as possible to the IN pin. See MAX1640 EV kit for layout example. (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information www ...