16-Bit, 500 kSPS PulSAR
®
Dual,
2-Channel, Simultaneous Sampling ADC
AD7654
Rev. B
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FEATURES
Dual, 16-bit, 2-channel simultaneous sampling ADC
16-bit resolution with no missing codes
Throughput:
500 kSPS (normal mode)
444 kSPS (impulse mode)
INL: ±3.5 LSB max (±0.0053% of full scale)
SNR: 89 dB typ @ 100 kHz
THD: −100 dB @ +100 kHz
Analog input voltage range: 0 V to 5 V
No pipeline delay
Parallel and serial 5 V/3 V interface
SPI®/QSPI™/MICROWIRE™/DSP compatible
Single 5 V supply operation
Power dissipation:
120 mW typical
2.6 mW @ 10 kSPS
Packages:
48-lead low profile quad flat package (LQFP)
48-lead lead frame chip scale package (LFCSP)
Low cost
APPLICATIONS
AC motor control
3-phase power control
4-channel data acquisition
Uninterrupted power supplies
Communications
FUNCTIONAL BLOCK DIAGRAM
CONTROL LOGIC AND
CALIBRATION CIRCUITRY
A/B
16
D[15:0]
BUSY
CS
SER/PAR
OGND
OVDD
DGND
D
DD
SERIAL
PORT
BYTESWAP
RD
DD
GND REFxREFGND
PD
RESET
CNVST
INAN
SWITCHED
CAP DAC
AD7654
INA1
IMPULSE
MUX
EOC
INA2
A0
INB1
INBN
INB2
TRACK/HOLD
×2
PARALLEL
INTERFACE
03057-001
CLOCK
MUX
MUX
Figure 1.
Table 1. PulSAR Selection
Type/kSPS 100 to 250 500 to 570 800 to 1000 >1000
Pseudo
Differential
AD7660/
AD7661
AD7653
AD7650/
AD7652
AD7664/
AD7666
AD7667
True Bipolar AD7663 AD7665 AD7671
True Differential AD7675 AD7676 AD7677 AD7621
AD7623
18-Bit AD7678 AD7679 AD7674 AD7641
Multichannel/
Simultaneous
AD7654 AD7655
GENERAL DESCRIPTION
The AD7654 is a low cost, simultaneous sampling, dual-
channel, 16-bit, charge redistribution SAR, analog-to-digital
converter that operates from a single 5 V power supply. It
contains two low noise, wide bandwidth, track-and-hold
amplifiers that allow simultaneous sampling, a high speed
16-bit sampling ADC, an internal conversion clock, error
correction circuits, and both serial and parallel system interface
ports. Each track-and-hold has a multiplexer in front to provide
a 4-channel input ADC. The A0 multiplexer control input
allows the choice of simultaneously sampling input pairs
INA1/INB1 (A0 = low) or INA2/INB2 (A0 = high). The part
features a very high sampling rate mode (normal) and, for low
power applications, a reduced power mode (impulse) where the
power is scaled with the throughput. Operation is specified
from −40°C to +85°C.
PRODUCT HIGHLIGHTS
1. Simultaneous Sampling.
The AD7654 features two sample-and-hold circuits that
allow simultaneous sampling. It provides inputs for four
channels.
2. Fast Throughput.
The AD7654 is a 500 kSPS, charge redistribution, 16-bit
SAR ADC with internal error correction circuitry.
3. Superior INL and No Missing Codes.
The AD7654 has a maximum integral nonlinearity of
3.5 LSB with no missing 16-bit codes.
4. Single-Supply Operation.
The AD7654 operates from a single 5 V supply. In impulse
mode, its power dissipation decreases with throughput.
5. Serial or Parallel Interface.
Versatile parallel or 2-wire serial interface arrangement is
compatible with both 3 V and 5 V logic.
