High Speed, 4-Channel, 8-Bit CMOS ADC

The AD7824 and AD7828 are high-speed, multichannel, 8-bit ADCs with a choice of 4 (AD7824) or 8 (AD7828) multiplexed analog inputs. A half-flash conversion technique gives a fast conversion rate of 2.5 µs per channel and the parts have a built-in track/hold function capable of digitizing full-scale signals of 10 kHz (157 mV/µs slew rate) on all channels. The AD7824 and AD7828 operate from a single +5 V supply and have an analog input range of 0 V to +5 V, using an external +5 V reference.

Microprocessor interfacing of the parts is simple, using standard Chip Select (CS) and Read (RD) signals to initiate the conversion and read the data from the three-state data outputs. The half-flash conversion technique means that there is no need to generate a clock signal for the ADC. The AD7824 and AD7828 can be interfaced easily to most popular microprocessors.

The AD7824 and AD7828 are fabricated in an advanced, all ion-implanted, Linear-Compatible CMOS process (LC2MOS) and have low power dissipation of 40 mW (typ). The AD7824 is available in a 0.3" wide, 24-pin "skinny" DIP, while the AD7828 is available in a 0.6" wide, 28-pin DIP and in 28- terminal surface mount packages.

* 4 or 8 Analog Input Channels

* Built-In Track-and-Hold Function

* 10 kHz Signal Handling on Each Channel

* Fast Microprocessor Interface