The LED2472G from STMicroelectronics is a 24-bit shift register providing a constant-current output to 24 channels of LEDs. It is intended for use in supplying current to the multiple LED channels in LED display panels, and particularly in interior and exterior LED billboards.
The LED2472G provides 20V of output driving capability, allowing several LEDs to be connected in series in each channel. The device is configured in three groups (red, green and blue) of eight independently-controlled channels. The LED current can be separately regulated for each colour within the range from 4mA to 72mA. This range is divided into two sub-ranges and the current can be adjusted within each range in 64 steps of resolution (6 bits per colour).
A single external resistor is required to configure the current. All the controls and the shift-register data are accessible via a serial interface. A single 24-bit configuration register is used to choose features and settings to fit the application.
An LED failure-detection circuit checks three different conditions which can occur at the output line: short to ground, short to the power supply rail, or open channel. The automatic shut-down and automatic power-on features allow the device to save power without any external intervention. An integrated step-down voltage regulator provides a supply voltage to the internal indicator-LED matrix driver and logic output buffers, and may be used to supply external optocouplers if the application requires isolation.
- 1A output current per channel
- 5.3mA supply current with all channels on 5V- and 3.3V-compatible I/Os
- Fast demagnetization of inductive loads
- Withstands ESD strikes up to 2kV
- Full-colour large displays
- LED signage
- Indoor/outdoor LED billboard screens