LC2MOS Single Supply,
12-Bit 600 kSPS ADC
Preliminary Technical Information
Fast 12-Bit ADC with 1.4 µs Conversion Time
Up to 600 kSPS Throughput Rate (Mode A)
Single Supply Operation
On-Chip Track/Hold Amplifier
Selection of Input Ranges:
±10 V or ±5 V for AD7889-1
0 V to +2.5 V or 0V to+5 V for AD7889-2
±2.5 V for AD7889-3
High Speed Serial Interface
Low Power, 60 mW typ
FUNCTIONAL BLOCK DIAGRAM
CONVST CONTCLK 16/14B
The AD7889 is a high speed, low power, 12-bit A/D converter
that operates from a single +5 V supply. The part contains a
successive approximation ADC, an on-chip track/hold ampli-
fier, an internal +2.5 V reference and on-chip versatile
interface structures that allows serial communication
to a microprocessor in a variety of operating modes. The part
accepts an analog input range of ±10 V or ±5 V (AD7889-1),
0 V to +2.5 V or 0 V to +5V (AD7889-2) and ±2.5 V
(AD7889-3). Overvoltage protection on the analog inputs for the
AD7889-1 and AD7889-3 allows the input voltage to go to
±17 V or ±7 V respectively without damaging the ports.
The AD7889 offers a choice of serial interface modes which al-
lows direct connection to the serial ports of microcontrollers
and digital signal processors.
In addition to the traditional dc accuracy specifications such as
linearity, full-scale and offset errors, the part is also specified
for dynamic performance parameters including harmonic dis-
tortion and signal-to-noise ratio.
The AD7889 is fabricated in Analog Devices Linear Compat-
ible CMOS (LC2MOS) process, a mixed technology process
that combines precision bipolar circuits with low power CMOS
logic. It is available in a 16-pin, SSOP.
1. The AD7889 features a conversion time of 1.4µs (Mode A)
and a track/hold acquisition time of 300ns. This allows a
throughput rate for the part up to 600 kSPS. Modes C and
D can be used to allow a throughput rate of 500kSPS.
2. The AD7889 operates from a single +5 V supply and con-
sumes 60 mW typ making it ideal for low power and por-
3. The part offers a high speed, serial interface for easy connec-
tion to microprocessors, microcontrollers and digital signal
Information furnished by Analog Devices is believed to be accurate and
reliable. However, no responsibility is assumed by Analog Devices for its
use, nor for any infringements of patents or other rights of third parties
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.
© Analog Devices, Inc., 1996
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.