FAN5333A/FAN5333B is a high-efficiency, high-current serial LED driver with a 30V integrated switch from Fairchild Semiconductor Corporation. The device has a 1.5MHz switching frequency, low noise, adjustable output voltage, up to 1.5A peak switch current and 1.5W output power capability.
The FAN5333A and FAN5333B are general‑purpose LED drivers that operate in a fixed‑frequency PWM mode with an integrated N‑channel FET switch. They provide up to 1.5 A peak switch current, low shutdown current (<1 µA), and feature cycle‑by‑cycle current limiting for reliable flash‑LED operation in handheld devices.
Typical applications include cell phones, PDAs, handheld equipment, and LED bias circuits. The device is supplied in a 5‑lead SOT‑23 package and requires external inductors (≈10 µH) and capacitors for optimal performance. Detailed electrical characteristics, pin assignments, and layout recommendations are provided for designers.
| Switching Frequency | 1.5 MHz |
|---|---|
| Peak Switch Current | 1.5 A |
| Feedback Voltage (FAN5333A) | 110 mV |
| Feedback Voltage (FAN5333B) | 315 mV |
| Quiescent (Shutdown) Current | <1 µA |
| Thermal Shutdown Temperature | 150 °C |
| Package Type | 5‑Lead SOT‑23 |
| Typical Inductor Value | 10 µH |
| Maximum Output Voltage | 30 V |
The device operates at a fixed switching frequency of 1.5 MHz.
The output current is set by a resistor divider between the FB pin and ground, using an internal reference of 110 mV for FAN5333A or 315 mV for FAN5333B.
The shutdown (OFF) current is less than 1 µA.
A typical inductance of 10 µH is recommended.