The IR3621 is a synchronous buck controller from IR company. It has high performance, low cost and flexibility. It can work in 2-phase mode to produce 2 independent voltages or current share single output for high current application. The IR3621 also has a variety of protection features such as selectable hiccup current limit or latched current limit, under voltage lockout.
The IR3621 integrates two synchronous buck controllers that can operate in either independent‑output mode or current‑share mode, providing flexible power‑conversion solutions for embedded networking, telecom and graphics applications. It features programmable soft‑start for each output, external frequency synchronization, and a precision 0.8 V reference.
Key specifications include a supply voltage range of 5.5 V–14.5 V, operating frequency up to 500 kHz per phase, and built‑in over‑voltage, under‑voltage lock‑out, thermal shutdown and current‑limit protection. The device is offered in 28‑pin TSSOP and 32‑lead MLPQ packages.
| High‑Side/Low‑Side Supply Voltage (VcH1, VcH2) Range | 10 V – 20 V |
|---|---|
| Operating Frequency | 200 kHz – 500 kHz |
| Maximum Output Current | 44 mA |
| Thermal Shutdown Trip Point | 140 °C |
| Package Types | 28‑pin TSSOP (F) / 32‑lead MLPQ 5 mm × 5 mm (M) |
The device provides two independently programmable soft‑start functions, one for each output.
The switching frequency can be programmed up to 500 kHz per phase.