FUNCTIONAL BLOCK DIAGRAM

AGND

V

REF

COMP

A CHIP

8

10

11

9

LEVEL TRANSLATORS

LOGIC TIMING

16-BIT

DAC

INPUT

BUFFERS

CAL

DAC

CLK

SAMPLE

D

CLK

OUT

D CHIP

3

14

AD1876

2

16

1

RAM

ALU

SAR

AGND SENSE

CAL

15 BUSY

MICROCODED

CONTROLLER

REV. A

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.

a

16-Bit 100 kSPS

Sampling ADC

AD1876

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.

Tel: 617/329-4700

Fax: 617/326-8703

FEATURES

Autocalibrating

0.002% THD

90 dB S/(N+D)

1 MHz Full Power Bandwidth

On-Chip Sample & Hold Function

2

Oversampling for Audio Applications

16-Pin DIP Package

Serial Twos Complement Output Format

Low Input Capacitance–typ 50 pF

AGND Sense for Improved Noise Immunity

PRODUCT DESCRIPTION

The AD1876 is a 16-bit serial output sampling A/D converter

which uses a switched capacitor/charge redistribution architecture

to achieve a 100 kSPS conversion rate (10

µs total conversion

time). Overall performance is optimized by digitally correcting

internal nonlinearities through on-chip autocalibration.

The circuitry of the AD1876 is partitioned onto two monolithic

chips, a digital control chip fabricated with Analog Devices’

DSP CMOS process and an analog ADC chip fabricated with

the BiMOS II process. Both chips are contained in a single

package.

The serial output interface requires an external clock and

sample command signal. The output data rate may be as high

as 2.08 MHz, and is controlled by the external clock. The twos

complement format of the output data is MSB first and is di-

rectly compatible with the NPC SM5805 digital decimation fil-

ter used in consumer audio products. The AD1876 is also

compatible with a variety of DSP processors.

The AD1876 is packaged in a space saving 16-pin plastic DIP

and operates from +5 V and

±12 V supplies; typical power con-

Separate analog and digital grounds are also provided.