The MAX1534 is a high-efficiency, triple-output power supply for keep-alive (always on) voltage rails. The 500mA buck regulator with an internal current-limited 0.5Ω 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 P-channel metal-oxide (PMOS) pass transistor to minimize supply current and deliver up to 160mA each of continuous current. The MAX1534 includes a power-OK (POK) signal that indicates all outputs are in regulation. The 4% accurate threshold of the active-low SHDN input permits its use as a low-battery detector. The MAX1534 is available in a small 16-pin thin QFN (4mm x 4mm) package, occupying 33% less board space than discrete solutions. Applications * 2 to 4 Li+ Cell Battery-Powered Devices * Handheld Devices * Keep-Alive Supplies * Notebook and Subnotebook Computers * Standby Supplies * Wake On LAN® * One Switching and Two Linear Regulators * Switching Regulator * +4.5V to +24V Input Voltage Range * Over 95% Efficiency * Up to 500mA Output Current * Up to 200kHz Switching Frequency * Fixed 5V or Adjustable Output Voltage * Internal 0.5Ω PMOS Switch * 100% Maximum Duty Cycle for Low-Dropout Operation * Two Low-Dropout Linear Regulators * Up to 160mA Output Current (Each) * 3.3V/Adj Output Voltage for OUT1 * 1.8V/Adj Output Voltage for OUT2 * ±1.5% Accurate Output Voltage * ±4% Accurate Shutdown for Low Battery Detection * Thermal Shutdown Protection * POK Output * 1mW Typical Standby Power https://elecena.pl/product/22316350/high-efficiency-triple-output-keep-alive-power-supply-for-notebook-computers 2022-12-27 https://elecena.pl/product/22316350/high-efficiency-triple-output-keep-alive-power-supply-for-notebook-computers 2024-10-06 https://elecena.pl/product/22316350/high-efficiency-triple-output-keep-alive-power-supply-for-notebook-computers 2024-11-06 https://elecena.pl/product/22316350/high-efficiency-triple-output-keep-alive-power-supply-for-notebook-computers 2025-01-22