AD7821KR High Speed, uP-Compatible 8-Bit ADC with Track/Hold Function by Analog Devices
DESCRIPTION: The AD7821 is a high speed, 8-bit, sampling, analog-to-digital
converter that offers improved performance over the popular
AD7820. It offers a conversion time of 660 ns (vs. 1.36 ms for
the AD7820) and 100 kHz signal bandwidth (vs. 6.4 kHz). The
sampling instant is better defined and occurs on the falling edge
of WR or RD. The provision of a VSS pin (Pin 19) allows the
part to operate from +/-5V supplies and to digitize bipolar input
signals. Alternatively, for unipolar inputs, the VSS pin can be
grounded and the AD7821 will operate from a single +5V supply,
like the AD7820.
The AD7821 has a built-in track-and-hold function capable of
digitizing full-scale signals up to 100 kHz max. It also uses a
half-flash conversion technique that eliminates the need to generate
a CLK signal for the ADC.
The AD7821 is designed with standard microprocessor control
signals (CS, RD, WR, RDY, INT) and latched, three-state data
outputs capable of interfacing to high speed data buses. An
overflow output (OFL) is also provided for cascading devices to
achieve higher resolution.
The AD7821 is fabricated in Linear-Compatible CMOS
(LC2MOS), an advanced, mixed technology process combining
precision bipolar circuits with low power CMOS logic. The part
features a low power dissipation of 50 mW.
FEATURES:
- Fast Conversion Time: 660 ns max
- 100 kHz Track-and-Hold Function
- 1 MHz Sample Rate
- Unipolar and Bipolar Input Ranges
- Ratiometric Reference Inputs
- No External Clock
- Extended Temperature Range Operation
These parts are new and unused.
