The ISL97631 is a high-efficiency, constant frequency PWM regulator with an integrated boost diode and FET. It is designed for use in white LED driving applications and offers efficiencies up to 85%. The regulator operates at a switching frequency of 1.35MHz and accepts input voltages between 2.7V and 5.5V. With a maximum output voltage of 27V, the ISL97631 can drive up to 6 LEDs in series. It can also be used to drive LEDs in series/parallel combinations for applications requiring up to 15 LEDs. The ISL97631 is available in a 6 Ld TSOT package and operates over a temperature range of -40°C to +85°C.
The ISL97631 is a high‑efficiency, constant‑frequency PWM regulator with an integrated boost diode and FET, designed for white LED backlighting and portable devices such as cell phones and PDAs. It operates from a 2.7 V to 5.5 V input and can drive up to six LEDs in series or up to fifteen LEDs in series/parallel configurations.
Key specifications include a maximum output voltage of 27 V, up to 85 % efficiency, a 1.35 MHz switching frequency, and operation over a –40 °C to +85 °C temperature range. The device is supplied in a 6‑lead TSOT package and supports PWM or analog dimming control via the ENAB pin.
| Input voltage range | 2.7 V to 5.5 V |
|---|---|
| Maximum output voltage | 27 V |
| Maximum LEDs in series | 6 LEDs |
| Efficiency | up to 85 % |
| Switching frequency | 1.35 MHz (constant) |
| Operating temperature range | -40 °C to +85 °C |
| Package type | 6‑lead TSOT |
The device operates from 2.7 V to 5.5 V input.
Up to six LEDs can be connected in series.
The regulator uses a constant 1.35 MHz switching frequency.
The ISL97631 can achieve up to 85 % efficiency.