ADC081C021 Datasheet | National Semiconductor

Description The ADC121C021 is a low-power, monolithic, 12-bit, analogto-digital converter(ADC) that operates from a +2.7 to 5.5V supply. The converter is based on a successive approximation register architecture with an internal track-and-hold circuit that can handle input frequencies up to 11MHz. The ADC121C021 operates from a single supply which also serves as the reference. The device features an I2C-patible 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 es in a small TSOT-6 package with an alert output. The ADC121C027 es in a small TSOT-6 package with an address selection input. The ADC121C027 provides three pin-selectable addresses. Pin-patible alternatives are available with additional address options. Normal power consumption using a +3V or +5V supply is 0.26m W or 0.78m W, respectively. The automatic powerdown feature reduces the power consumption to less than 1µW while not converting. Operation over the industrial temperature range of - 40°C to +105°C is guaranteed. Their low power consumption and small packages make this family of ADCs an excellent choice for use in battery operated equipment. The ADC121C021 and ADC121C027 are part of a family of pin-patible ADCs that also provide 8 and 10 bit resolution. For 8-bit ADCs see the ADC081C021 and ADC081C027. For 10-bit ADCs see the ADC101C021 and ADC101C027. Features - I2C-patible 2-wire Interface which supports standard - - - - - - (100k Hz), fast (400k Hz), and high speed (3.4MHz) modes Extended power supply range (+2.7V to +5.5V) Up to four pin-selectable...