The MAX1973EUB+ is a smallest constant frequency step down regulator in 10 pin μMAX package. The output voltage of this pulse width modulated (PWM) current mode step down regulator can be set as low as 1.25V (1.25V to VIN) using an external voltage divider or it can be set to preset outputs of 1.8V or 2.5V without requiring external resistors. The MAX1973 also includes voltage margining feature that offsets output voltage up or down 4% to facilitate board level production testing. Only 4.7μF input and output ceramic capacitors are needed for 1A applications. Forced PWM operation ensures a constant switching frequency over all load conditions. Output voltage accuracy is ±1% over load, line and temperature operating ranges. The MAX1973 is used in network equipments, cellular base stations, DSL and wireless modems/routers optical modules, central office DSL and telecoms, DSP/ASIC core and IO supplies.
Input voltage range from 2.6V to 5.5V
Operating temperature range from -40°C to 85°C
Supply current of 4mA and shutdown supply current of 0.1μA
Tiny circuit footprint of 0.19in2
Ultra low circuit height of 1.8mm
Output current of 1A
Fixed frequency PWM current mode operation
100% duty cycle dropout capability
Fixed 1.4MHz operating frequency ensures operation outside DSL frequency band
Fast transient response and only small external components required
(EN)
