AD7934-6 Datasheet, PDF (1/28 Pages) Analog Devices – 4-Channel, 625 kSPS, 12-Bit Parallel ADC with a Sequencer

FEATURES
Throughput rate: 625 kSPS
Specified for VDD of 2.7 V to 5.25 V
Power consumption
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
±0.2% max @ 25°C, 25 ppm/°C max
70 dB SINAD at 50 kHz input frequency
No pipeline delays
High speed parallel interface—word/byte modes
Full shutdown mode: 2 µA max
28-lead TSSOP package
GENERAL DESCRIPTION
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.
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, which allow for easy interfacing to microprocessors and
DSPs. The input signal is sampled on the falling edge of 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
conversion. Alternatively, this pin can be overdriven to provide
an external reference.
Rev. A
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4-Channel, 625 kSPS, 12-Bit
Parallel ADC with a Sequencer
AD7934-6
V_REFIN/
V_REFOUT
V_IN0
V_IN3
FUNCTIONAL BLOCK DIAGRAM
V_DD
AGND
AD7934-6
2.5V
VREF
I/P
MUX
T/H
12-BIT
SAR ADC
AND
CONTROL
CLKIN
CONVST
BUSY
SEQUENCER
PARALLEL INTERFACE/CONTROL REGISTER
V_DRIVE
DB0 DB11
CS RD WR W/B
Figure. 1
DGND
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.
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.
6. Accurate control of the sampling instant via a CONVST input
and once off conversion control.
Table 1. Related Devices
Similar
Device
Number
of Bits
AD7938/39 12/10
AD7933/34 10/12
AD7938-6 12
Number of
Channels
8
4
8
Speed
1.5 MSPS
1.5 MSPS
625 kSPS
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