The L5973AD is a step down monolithic power switching regulator produced by ST. The maximum operating voltage is 36V and the maximum output current is 2A. The output voltage can be adjusted in the range of 1.235V-35V. The chip uses an internal P-channel DMOS transistor as the switching element, an internal oscillator fixes the working frequency at 500KHz, and has high efficiency, low power consumption, and good EMI performance. It is suitable for 5V power bus and can be widely used in consumer electronics, network equipment, computers, and industrial fields.
The L5973AD is a 2 A step‑down switching regulator with an internal P‑channel MOSFET, fixed 500 kHz switching frequency and a 3.3 V reference. It operates from 4.4 V to 36 V input and delivers an adjustable output from 1.235 V to 35 V, suitable for consumer, networking, computer and industrial applications.
The manual details the functional blocks, pin functions, thermal data, electrical specifications, protection features (over‑voltage, thermal shutdown, feedback disconnection) and synchronization options. It also includes application circuits, revision history and regulatory notices.
| Operating input voltage range | 4.4 V to 36 V |
|---|---|
| Adjustable output voltage range | 1.235 V to 35 V |
| Switching frequency | 500 kHz (fixed) |
| Maximum output current | 2 A (switch current limit) |
| Efficiency (typical) | 90 % (Vo=5 V, Vcc=12 V) |
| Quiescent current | 5.7 mA (total operating) |
| Operating temperature range | -40 °C to 150 °C |
The device can operate with an input voltage up to 36 V.
Thermal shutdown triggers when the chip temperature exceeds 150 °C.