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
