4-Channel, 625 kSPS, 12-Bit
Parallel ADC with a Sequencer
AD7934-6
FUNCTIONAL BLOCK DIAGRAM
FEATURES
Throughput rate: 625 kSPS
V
AGND
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 max at 625 kSPS with 3 V supplies
7.5 mW max at 625 kSPS with 5 V supplies
4 analog input channels with a sequencer
Software configurable analog inputs
4-channel single-ended inputs
2-channel fully differential inputs
2-channel pseudo differential inputs
Accurate on-chip 2.5 V reference
0.2ꢀ max @ 25°C, 25 ppm/°C max
70 dB SINAD at 50 kHz input frequency
No pipeline delays
VREF
V
V
0
IN
IN
CLKIN
12-BIT
SAR ADC
AND
I/P
CONVST
T/H
MUX
CONTROL
BUSY
3
SEQUENCER
V
PARALLEL INTERFACE/CONTROL REGISTER
DRIVE
High speed parallel interface—word/byte modes
Full shutdown mode: 2 µA max
28-lead TSSOP package
DB0 DB11
CS RD WR W/B
DGND
Figure. 1
GENERAL DESCRIPTION
The AD7934-6 uses advanced design techniques to achieve very
low power dissipation at high throughput rates. The part also
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
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.
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.
Data acquisition and conversion are controlled by standard control
inputs, which allow for easy interfacing to microprocessors and
5. No pipeline delay.
DSPs. The input signal is sampled on the falling edge of
,
CONVST
6. Accurate control of the sampling instant via a
and once off conversion control.
input
CONVST
which is also the point where the conversion is initiated.
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
Table 1. Related Devices
conversion. Alternatively, this pin can be overdriven to provide
an external reference.
Similar
Device
Number
of Bits
Number of
Channels
Speed
AD7938/39
AD7933/34
AD7938-6
12/10
10/12
12
8
4
8
1.5 MSPS
1.5 MSPS
625 kSPS
Rev. A
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