4-Channel, 625 kSPS, 12-Bit
Parallel ADC with a Sequencer
AD7934-6
FUNCTIONAL BLOCK DIAGRAM
FEATURES
V
AGND
Throughput rate: 625 kSPS
DD
Specified for VDD of 2.7 V to 5.25 V
Power consumption
AD7934-6
V
/
REFIN
V
REFOUT
2.5V
3.6 mW maximum at 625 kSPS with 3 V supplies
7.5 mW maximum at 625 kSPS with 5 V supplies
4 analog input channels with a sequencer
Software-configurable analog inputs
4-channel single-ended inputs
VREF
V
0
IN
IN
CLKIN
CONVST
BUSY
12-BIT
SAR ADC
AND
I/P
MUX
T/H
CONTROL
V
3
2-channel fully differential inputs
2-channel pseudo differential inputs
Accurate on-chip 2.5 V reference
0.2ꢀ maximum @ 25°C, 25 ppm/°C maximum
70 dB SINAD at 50 kHz input frequency
No pipeline delays
SEQUENCER
V
PARALLEL INTERFACE/CONTROL REGISTER
DRIVE
High speed parallel interface—word/byte modes
Full shutdown mode: 2 μA maximum
28-lead TSSOP package
DB0 DB11
CS RD WR W/B
DGND
Figure. 1
GENERAL DESCRIPTION
features flexible power management options. An on-chip control
register allows the user to set up different operating conditions,
including analog input range and configuration, output coding,
power management, and channel sequencing.
The AD7934-6 is a 12-bit, high speed, low power, successive
approximation (SAR) analog-to-digital converter (ADC). The
part operates from a single 2.7 V to 5.25 V power supply and
features throughput rates up to 625 kSPS. The part contains a
low noise, wide bandwidth, differential track-and-hold
amplifier that handles input frequencies up to 50 MHz.
PRODUCT HIGHLIGHTS
1. High throughput with low power consumption.
2. Four analog inputs with a channel sequencer.
3. Accurate on-chip 2.5 V reference.
4. Single-ended, pseudo differential, or fully differential
analog inputs that are software selectable.
5. No pipeline delay.
The AD7934-6 features four analog input channels with a channel
sequencer that allows a preprogrammed selection of channels to
be converted sequentially. This part can accept either single-
ended, fully differential, or pseudo differential analog inputs.
Data acquisition and conversion are controlled by standard control
inputs that allow for easy interfacing to microprocessors and
CONVST
6. Accurate control of the sampling instant via a
input and once-off conversion control.
CONVST
DSPs. The input signal is sampled on the falling edge of
,
which is also the point where the conversion is initiated.
Table 1. Related Devices
The AD7934-6 has an accurate on-chip 2.5 V reference that
can be used as the reference source for the analog-to-digital
conversion. Alternatively, this pin can be overdriven to provide
an external reference.
Similar Device
AD7938/AD7939
AD7933/AD7934
AD7938-6
No. of Bits No. of Channels
Speed
12/10
10/12
12
8
4
8
1.5 MSPS
1.5 MSPS
625 kSPS
The AD7934-6 uses advanced design techniques to achieve very
low power dissipation at high throughput rates. The part also
Rev. B
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 that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registeredtrademarks arethe property of their respective owners.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700 www.analog.com
Fax: 781.461.3113 ©2005–2007 Analog Devices, Inc. All rights reserved.