GENERAL DESCRIPTION
The device features an I2C-compatible serial interface that operates in all three speed modes, including high speed mode (3.4MHz). The ADC's Alert feature provides an interrupt that is activated when the analog input violates a programmable upper or lower limit value. The device features an automatic conversion mode, which frees up the controller and I2C interface. In this mode, the ADC continuously monitors the analog input for an "out-of-range" condition and provides an interrupt if the measured voltage goes out-of-range. The ADC121C021 comes in a small TSOT-6 package with an alert output. The ADC121C027 comes in a small TSOT-6 package with an address selection input. The ADC121C027 provides three pin-selectable addresses. Pin-compatible alternatives are available with additional address options. Normal power consumption using a +3V or +5V supply is 0.26mW or 0.78mW, respectively. The automatic powerdown feature reduces the power consumption to less than 1µW while not converting.
National Semiconductor
