The XC9503 series are multi‑functional, 2‑channel step‑down DC/DC controller ICs that support PWM or PWM/PFM automatic switching. They feature a built‑in 0.9 V reference, selectable output voltage from 0.9 V to 6 V, and a soft‑start time of 10 ms to limit in‑rush current.
Typical applications include PDAs, palmtop computers, digital cameras and various multi‑function power supplies. The device is offered in MSOP‑10 and USP‑10 packages and complies with EU RoHS directives.
| Input Voltage Range | 2.0 V – 10 V |
|---|---|
| Output Voltage Range | 0.9 V – 6.0 V (set by FB pins) |
| Oscillation Frequency | 300 kHz (±15 %) |
| Efficiency | 92 % |
| Soft‑Start Time | 10 ms (internally set) |
| Maximum Duty Cycle | 100 % |
| Stand‑by Current | 3.0 mA (MAX.) |
| Package Types | MSOP‑10, USP‑10 |
The IC can operate in PWM mode or PWM/PFM automatic switching mode, selectable via external signals.
Output voltage is set by external split resistors on the FB pins using the formula VOUT = 0.9 × (RFB11+RFB12)/RFB12.
The soft‑start time is internally fixed at 10 ms.
The controller can reach a maximum duty cycle of 100 %.