The ISL97634 is an efficient and highly integrated PWM boost LED driver that is suitable for 1.8” to 3.5” LCDs that employ 2 to 7 white LEDs for backlighting. The ISL97634 features a wide range of PWM dimming control capability. It allows dimming frequency as low as DC to 32kHz beyond audible spectrum. The ISL97634 also features a feedback disconnect switch to prevent the output from being modulated by the PWM dimming signal that minimizes system disturbance. The ISL97634 is available in the 8 Ld TDFN (2mmx3mm) package. There are 14V, 18V, and 26V OVP options that are suitable for 3 LEDS, 4 LEDs, and 7 LEDs (3.5V/20mA type) backlight applications respectively. The ISL97634 is specified for operation over the -40°C to +85°C ambient temperature at input voltage from 2.4V to 5.5V.
The ISL97634 LED driver provides a wide PWM dimming range (DC to 32 kHz) and integrated features such as a Schottky diode, over‑voltage protection (OVP) and a feedback disconnect switch. It is offered in an 8‑L D TDFN (2 mm × 3 mm) package and operates from 2.4 V to 5.5 V input voltage, making it suitable for portable LCD backlight applications.
Typical applications include cell‑phone, automotive navigation panel and portable GPS backlighting. The datasheet includes absolute maximum ratings, electrical specifications, pin descriptions, typical application circuits, performance curves, and design notes for analog dimming, SEPIC operation and PCB layout.
| Package | 8‑L D TDFN (2 mm × 3 mm) |
|---|---|
| Efficiency | 85 % |
| Shutdown current | 1 pA |
| LED drive capability | Up to 7 LEDs in series (3.5 V/20 mA type) |
| Switching frequency | ≈1.4 MHz |
It can drive up to 7 white LEDs in series (3.5 V/20 mA type).
OVP thresholds are 14 V for 3 LEDs, 18 V for 4 LEDs, and 26 V for 7 LEDs.