The IR3637A is a synchronous Buck controller IC designed for low-cost DC to DC power conversion applications. It features an internal 0.8V reference voltage for precise voltage regulation for low-voltage applications. The device operates at a fixed 600KHz switching frequency to reduce component size.
The IR3637ASPbF is a fixed‑frequency, voltage‑mode synchronous buck controller designed for low‑voltage applications. It features a 0.8 V internal reference, soft‑start, under‑voltage lockout, short‑circuit protection, and a 600 kHz internal oscillator. The device is supplied in an 8‑pin SOIC package and is intended for use in computer peripherals, memory power supplies, graphics cards, and other consumer‑grade DC‑to‑DC conversion circuits.
The datasheet provides absolute maximum ratings, recommended operating conditions, electrical specifications, pin descriptions, and detailed design guidelines, including soft‑start programming, inductor and capacitor selection, and feedback compensation. Application examples and a typical circuit diagram illustrate how to set the output voltage and program the soft‑start function.
| Reference Voltage | 0.8 V |
|---|---|
| Oscillator Frequency | 600 kHz |
| Supply Voltage Range (Vee) | 5.5 V – 14 V |
| Static Supply Current (Vcc) | 1 mA – 6 mA |
| Soft‑Start Current | 25 pA |
| Package Type | 8‑pin SOIC (narrow body) |
The internal oscillator runs at a fixed frequency of 600 kHz.
Soft‑start is programmed by connecting an external capacitor to pin ss/SD; the capacitor value sets the start‑up time.
Pin 5 (HDrv) is the output driver for the high‑side power MOSFET.