AD7653_15 Datasheet, PDF (8/28 Pages) Analog Devices – 16-Bit 1 MSPS PulSAR Unipolar ADC with Reference

AD7653
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
48 47 46 45 44 43 42 41 40 39 38 37
AGND 1
AVDD 2
NC 3
BYTESWAP 4
OB/2C 5
WARP 6
IMPULSE 7
SER/PAR 8
D0 9
D1 ¹⁰
D2/DIVSCLK0 11
D3/DIVSCLK1 12
PIN 1
IDENTIFIER
AD7653
TOP VIEW
(Not to Scale)
36 AGND
35 CNVST
34 PD
33 _RESET
32 CS
31 _RD
30 _DGND
29 _BUSY
28 D15
27 D14
26 D13
25 D12
NC = NO CONNECT
13 14 15 16 17 18 19 20 21 22 23 24
02966-0-002
Table 6. Pin Function Descriptions
Pin No. Mnemonic
Type¹
1, 36, AGND
P
41, 42
2, 44
AVDD
P
3, 40
NC
4
BYTESWAP
DI
5
OB/2C
DI
6
WARP
DI
7
IMPULSE
DI
8
SER/PAR
DI
9, 10
D[0:1]
DO
11, 12 D[2:3]or
DI/O
DIVSCLK[0:1]
13
D4 or
DI/O
EXT/INT
14
D5 or
DI/O
INVSYNC
Figure 4. 48-Lead LQFP (ST-48) and 48-Lead LFCSP (CP-48)
Description
Analog Power Ground Pin.
Input Analog Power Pin. Nominally 5 V.
No Connect.
Parallel Mode Selection (8-/16-bit). When LOW, the LSB is output on D[7:0] and the MSB is output on
D[15:8]. When HIGH, the LSB is output on D[15:8] and the MSB is output on D[7:0].
Straight Binary/Binary Twos Complement. When OB/2C is HIGH, the digital output is straight binary;
when LOW, the MSB is inverted, resulting in a twos complement output from its internal shift
register.
Mode Selection. When this pin is HIGH and the IMPULSE pin is LOW, this input selects the fastest
mode, the maximum throughput is achievable, and a minimum conversion rate must be applied in
order to guarantee full specified accuracy. When LOW, full accuracy is maintained independent of
the minimum conversion rate.
Mode Selection. When IMPULSE is HIGH and WARP is LOW, this input selects a reduced power
mode. In this mode, the power dissipation is approximately proportional to the sampling rate.
Serial/Parallel Selection Input. When LOW, the parallel port is selected; when HIGH, the serial
interface mode is selected and some bits of the DATA bus are used as a serial port.
Bit 0 and Bit 1 of the Parallel Port Data Output Bus. When SER/PAR is HIGH, these outputs are in high
impedance.
When SER/PAR is LOW, these outputs are used as Bit 2 and Bit 3 of the parallel port data output bus.
When SER/PAR is HIGH, EXT/INT is LOW, and RDC/SDIN is LOW (serial master read after convert),
these inputs, part of the serial port, are used to slow down, if desired, the internal serial clock that
clocks the data output. In other serial modes, these pins are not used.
When SER/PAR is LOW, this output is used as Bit 4 of the parallel port data output bus.
When SER/PAR is HIGH, this input, part of the serial port, is used as a digital select input for choos-
ing the internal data clock or an external data clock. With EXT/INT tied LOW, the internal clock is
selected on the SCLK output. With EXT/INT set to logic HIGH, output data is synchronized to an
external clock signal connected to the SCLK input.
When SER/PAR is LOW, this output is used as Bit 5 of the parallel port data output bus.
When SER/PAR is HIGH, this input, part of the serial port, is used to select the active state of the
SYNC signal. It is active in both master and slave modes. When LOW, SYNC is active HIGH. When
HIGH, SYNC is active LOW.
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