ZXLD1321：Low Voltage DC-DC LED Drivers
| Part Number | Data Sheet | SPICE Model | Topologies (Buck) | Topologies (Buck-Boost) | Topologies (Boost) | MinimumInput Voltage (V) | MaximumInput Voltage (V) | Maximum Output Voltage (V) | LED Current (A) | Switching Frequency (kHz) | Efficiency (%) | OperatingTemperatureRange (°C) | QuiescentCurrentTyp (mA) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ZXLD1321 | ZXLD1321.pdf | - | - | - | Yes | 1.2 | 12 | 18 | 1 | 600 | 85 | -40 to +85 | 1.5 |
Description
The ZXLD1321 is an inductive DC-DC converter, with an internal switch, designed for driving single or multiple °Cs in series up to a total of 1A output current. Applications cover commercial environments with input voltages ranging from 1.2V to 12V. The device employs a variable 'on' and 'off' time control scheme with adjustable peak switch current limiting and supports step-up (Boost) mode and self-powering Bootstrap operating modes, offering higher power efficiency and lower system cost than conventional PFM circuitry. The device includes the DC-DC converter, a high-side current monitor and an NPN switching transistor to provide an integrated solution offering small PCB size, competitive cost/performance, high power efficiency of DC-DC conversion and maximum °C brightness/reliability. More importantly, it retains design flexibility to add customer specific features. The feedback control circuitry inside the ZXLD1321 provides excellent load and current regulation, resulting in very stable °C current over the useful life of the battery and over the full operating temperature range. The °C current can be adjusted from 100% down to 10% of the set value by applying a dc voltage to the ADJ pin and down to 1% by applying a PWM signal to the ADJ pin. An onchip °C protection circuit also allows output current to be reduced linearly above a predetermined threshold temperature using an external thermistor at the TADJ pin. External resistors set nominal average °C current and coil peak current independently. The device can be shut down by applying a continuous low level dc voltage to the ADJ pin.
Application
- High power LED flashlights
- LED back-up lighting
- General LED lighting
- Emergency lighting
Features
- 1.2V to 12V Input voltage range
- Up to 1A output current
- Typical efficiency >85%
- Bootstrap operation enables input voltage down to 1V
- User-defined thermal control of °C output current using external thermistor
- High output current stability over input voltage and temperature
- 12μA typical standby current
- °C current adjustable from 100% down to 2%
- Adjustable soft-start
- Drives up to 5 white °Cs in series
Ordering Information
- ZXLD1321DCATC
DFN4030-14
- ZXLD1321.pdf ZXLD1321
