The MAX1686HEUA+T provides power for dual-voltage subscriber ID module (SIM) cards in portable applications such as GSM cellular phones. Designed to reside in the portable unit (cellular phone handset), the 1MHz charge pump converts a 2.7V to 4.2V input to regulated 5V output. The MAX1686H has a nominal output voltage of 5.0V, while the MAX1686HEUA+T is set to 4.75V to reduce SIM card current drain. The charge pump has only 45μA quiescent supply current, which reduces to 3μA when a 3V-capable SIM card is being powered and the charge pump is disabled. An internal input/output shorting switch provides power for 3V SIM cards. The MAX1686/MAX1686H require only three external capacitors around their space-saving, thin (1mm) 8-pin μMAX packages.
Feature
- 2.7V to 4.2V Input Range
- 12mA min Charge-Pump Output Current
- 45μA Quiescent Supply Current
- 0.1μA Supply Current in Shutdown Mode
- 5.0V Regulated Charge-Pump Output (MAX1686H)
- 4.75V Regulated Charge-Pump Output (MAX1686)
- Input-Output Shorting Switch for 3V Cards
- Small External Components (Uses a 0.047μF, 0.1μF, and a 2.2μF Capacitor)
- Output Driven to Ground in Shutdown Mode
- Super-Small 8-Pin μMAX Package
- Soft-Start and Short-Circuit Protection
- Regulated charge pump for SIM cards nominal output voltage of 5.0V (MAX1686H)
Applications
- GSM Cellular Phones
- PCS Phones
- Personal Communicators
- Portable POS Terminals
