Smallest, Highest Efficiency White LED Charge Pump Packaged in a UCSP™
The MAX1573 fractional charge pump drives up to four white LEDs with regulated constant current for uniform intensity. By utilizing proprietary adaptive 1x/1.5x modes and ultra-low-dropout current regulators, it maintains the highest possible efficiency over the full 1-cell Li+ battery input voltage range. The 1MHz fixed-frequency switching allows for tiny external components and the regulation scheme is optimized to ensure low EMI and low input ripple. An external resistor sets the full-scale LED current, while two digital inputs control on/off and select amongst three levels of brightness. A pulse-width modulation (PWM) signal can also be used to modulate LED brightness, requiring no additional components. The MAX1573 is available in the tiny chip-scale UCSP™ (4 x 4 grid) and 16-pin thin QFN packages.
title | Download file |
---|---|
MAX1573 Data Sheet | MAX1573.pdf |
Part Number | Battery Input | Regulation Topology | Max. No. of LEDs | LED Channels | LED Configuration | ILED per Channel (A) | PWM Dimming Freq. (kHz) | Dimming Control | POUT (W) | VIN (V) | VIN (V) | ICC (mA) | LED String Volt. (V) | Oper. Freq. (kHz) | Package/Pins | Budgetary Price |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
max | max | min | max | max | max | See Notes | ||||||||||
MAX1573 | 1-Cell Li+ | Charge Pump | 4 | 4 | Parallel | 0.028 | 50 | Digital PWM | 0.5 | 2.7 | 5.5 | 4 | 5 | 1000 | TQFN/16 UCSP/16 | $1.93 @1k |
Part Number | Status | Recommended Replacement | Package | Temp | RoHS |
---|---|---|---|---|---|
MAX1573EBE-T | No Longer Available | UCSP,;16 pin;4.3 mm² | -40°C to +85°C | No | |
MAX1573ETE | No Longer Available | MAX1573ETE+ | TQFN,;16 pin;16.8 mm² | -40°C to +85°C | No |
MAX1573ETE+ | Active | TQFN,;16 pin;16.8 mm² | -40°C to +85°C | Lead Free | |
MAX1573ETE+T | Active | TQFN,;16 pin;16.8 mm² | -40°C to +85°C | Lead Free | |
MAX1573ETE-T | No Longer Available | MAX1573ETE+T | QFN;16 pin | -40°C to +85°C | See data sheet |
MAX1573TQFNEVKIT | Active | EVKIT; | -40°C to +85°C | See data sheet |