Datasheet for the PCF8591, an 8-bit data acquisition device from Philips/NXP combining four analog inputs, one analog output and an I2C serial interface on a single supply. The compact 140 KB PDF covers pinout, address pins, control byte format, reference voltage handling and electrical characteristics. Technicians use it to check I2C SDA and SCL lines, set the hardware address and verify analog references when a sensor board or module misbehaves. Pull-up resistors on the bus are required.
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