HOW DOES IT WORK?

LED Driver 18 Click is based on the TLC5947, a 24-channel 12-bit PWM LED driver from Texas Instruments. Each channel supports many LEDs in series connected to the LED terminal, and has an individually-adjustable 4096-step PWM grayscale brightness control accessible through a serial interface port. It has a programmable current value of all 24 channels achievable through the AD5171, an I2C-configurable digital potentiometer, with a maximum of 30mA of LED current per channel. The TLC5947 also features a built-in thermal shutdown function that turns OFF all output drivers during an over-temperature condition. All channels automatically restart when the temperature returns to normal conditions.

LED Driver 18 Click communicates with MCU through a register-selectable standard SPI interface that enables a high clock speed of up to 30MHz for optimum performance. In addition to the interface signals, the TLC5947 uses another signal from the mikroBUS™ socket. The enable signal routed on the EN pin of the mikroBUS™ socket provides the ability to turn OFF all constant-current outputs. When the EN pin is in a high logic state, all channels (0-23) are forced OFF, the grayscale PWM timing controller initializes, and the grayscale counter resets to 0. When the EN pin is in a low logic state is low, the grayscale PWM timing controller controls all LED channels.

This Click board™ can operate with either 3.3V or 5V logic voltage levels selected via the VCC SEL jumper. This way, both 3.3V and 5V capable MCUs can use the communication lines properly. However, the Click board™ comes equipped with a library containing easy-to-use functions and an example code that can be used, as a reference, for further development.

SPECIFICATIONS