The MAX1534ETE+ from Maxim Integrated Products is a high-efficiency, triple-output, keep-alive power supply for notebook computers in 16 pin TQFN package. The 500mA buck regulator with an internal current-limited 0.5ohm PMOS steps down the battery or wall adapter supply rail to a fixed 5V or an adjustable output voltage. Two integrated low voltage linear regulators follow this output and provide two independent preset output voltages of 3.3V and 1.8V or adjustable output voltages. The buck regulator utilizes a peak current-limit, pulse frequency modulation (PFM) architecture for highest light-load efficiency to conserve battery life. High switching frequencies (up to 200KHz) allow the use of tiny surface-mount inductors and output capacitors. Operation to 100% duty cycle minimizes dropout voltage (250mV at 500mA). The low-dropout linear regulators use an internal PMOS pass transistor to minimize supply current and deliver up to 160mA each of continuous current.
● Input voltage range from +4.5V to +24V
● Over 95% efficiency
● Two low dropout linear regulators up to 160mA output current (each)
● ±1.5% accurate output voltage
● ±4% accurate shutdown for low battery detection
● Thermal shutdown protection
● Power-OK (POK) signal that indicates all outputs are in regulation
● 1mW typical standby power
● Operating temperature range from -40°C to 85°C
