XC6121/XC6122/XC6123/XC6124 series voltage detector with watchdog function and ON/OFF control
The XC6121/XC6122/XC6123/XC6124 series are CMOS‑process voltage detectors that provide a fixed detect voltage from 1.6 V to 5.0 V in 0.1 V steps. They integrate a reference source, delay circuit, comparator and output driver, and include a watchdog timer that can be enabled or disabled via the EN/ENB pin.
Typical applications include microprocessor watchdog monitoring, memory‑backup circuits, power‑on reset, and power‑failure detection. The devices are offered in compact SOT‑25 and USP‑6C packages and meet RoHS requirements.
| Detect Voltage Range | 1.6 V ~ 5.0 V |
|---|---|
| Hysteresis Width | VDFL × 5 % (typ.) |
| Operating Voltage Range | 1.0 V ~ 6.0 V |
| Output Configuration | N‑channel open drain |
| Watchdog Timeout Periods | 50 ms, 100 ms, 200 ms, 400 ms, 800 ms, 1.6 s |
| Release Delay Times | 3.13 ms, 50 ms, 100 ms, 200 ms, 400 ms (typ.) |
| Package Types | SOT‑25, USP‑6C |
The watchdog function is forced off when the EN/ENB pin voltage is set to low (EN) or high (ENB) level.
Six timeout periods are selectable: 50 ms, 100 ms, 200 ms, 400 ms, 800 ms, and 1.6 s.
The RESETB pin provides an open‑drain low output when the detect voltage is reached.