HOW DOES IT WORK?

ADC 20 Click is based on the TLA2518, a small, eight-channel, multiplexed, 12-bit, 1-MSPS, analog-to-digital converter (ADC) from Texas Instruments. The TLA2518 comes with an internal oscillator for the ADC conversion process and supports averaging multiple data samples with a single conversion start. Also, the built-in programmable averaging filters, which output a 16-bit result for enhanced resolution, help reduce noise from the analog inputs and the number of data samples required to be read by the host MCU. The analog input channel selection can be auto-sequenced to simplify the digital interface with the host MCU.

This Click board™ communicates with MCU through a standard SPI interface, supporting all four SPI-compatible protocols (SPI Mode 0, 1, 2, and 3) to access the device, and operates at clock rates up to 60MHz for all configurations and information management and acquiring conversion results. As mentioned before, the TLA2518 powers up in Manual mode and can be configured into either of three operational modes by writing the configuration registers for the desired mode.

The Manual mode allows the host MCU to directly select the analog input channel, while in the second, the On-the-Fly mode of operation, the analog input channel is set using the first five bits on the SDI signal without waiting for the CS rising edge. This way, the ADC samples the newly selected channel on the CS edge, and there is no latency between the channel selection and the ADC output data. In the third Auto-Sequence mode, the internal channel sequencer switches the multiplexer to the next analog input channel after every conversion.

In addition to the fact that all eight channels, including also channels on the side headers, can be used as analog input pins, this board allows for some channels, in this case, channels CH0, CH1, CH6, and CH7 of the TLA2518 to be configured as digital inputs, open-drain digital outputs, and push-pull digital outputs.

This Click board™ can operate with both 3.3V and 5V logic voltage levels selected via the VCC SEL jumper. This way, it is allowed for both 3.3V and 5V capable MCUs to 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