PCF8591 ADC-DAC

PCF8591 ADC-DAC is a monolithically integrated, separate power supply, and low-power device. This is a breakout board with a single-chip, 8-bit CMOS data acquisition device for PCF8591 IC. The PCF8591 ADC-DAC consists of four analogue inputs and one analogue output. It communicates via a serial I2C bus interface. Three address pins A0, A1, and A2 are used in programming the hardware address. This allows the use of up to eight devices connected to the I²C‑bus without additional hardware.

Address, control, and data signals transmitted in serial via a two-wire bidirectional I2C bus. The maximum conversion rate determines the maximum speed of the I²C-bus. PCF8591 is an 8 bit analogue to digital or 8 bit digital to analogue converter module which can read analogue values up to 256. LDR and thermistor circuit is provided on the board. This indicates the precise value of light intensity and temperature of the module. There are SCL and SDA pins for serial clock and serial data address which requires 2.5-6V supply voltage. As a result, provides a low standby current in the I2C bus interface.

The knob of the potentiometer adjusts the input voltage on the module. There are also three jumpers on the board J4, J5, J6. J4 is connected to select the thermistor access circuit, J5 to select the LDR/photoresistor access circuit, and J6  to select the adjustable voltage access circuit. Two LEDs in the module indicates the output voltage intensity and the intensity of the supply voltage. So higher the output or supply voltage gives the high intensity of the LED. These LEDs can also test using a potentiometer on VCC or on an AOUT pin. PCF8591 features analogue input multiplexing, on-chip track and hold function, 8-bit analogue-to-digital conversion, and an 8‑bit digital-to-analogue conversion.