EVAL-AD7899CB Datasheet, PDF (4/12 Pages) –

EVAL-AD7899CB
EVALUATION BOARD INTERFACING
Interfacing to the evaluation board is via a 96-way connector,
J1. J1 is used to connect the evaluation board to the EVAL-
BOARD CONTROLLER or other system. The pinout for
the J1 connector is shown in Figure 2 and its pin designations
are given in Table II.
1
32
A
B
C
1
32
Fig. 2. Pin Configuration for the 96-Way Connector, J1
96-Way Connector Pin Description
FL1
Flag one. This is a logic input and is connected
to the STBY pin of the AD7899. A logic high on
this pin allows normal operation of the AD7899.
A logic low on this pin puts the AD7899 into
standby mode.
D0-D13 Data Bit 0 to Data Bit 13. Bi-directional data
pins. These data bits provide the ADC conversion
results during a read operation.
RD
Read. This is an active low logic input which is
used in conjunction with the CS pin to enable the
data outputs.
WR
Write. A logic input. A rising edge on this input,
with CS low and RD high latches the logic state
on D0-D3 into the channel select register. Soft-
ware selection of channels is not supported by this
evaluation board.
CS
Chip Select. An active low logic input. A low
level on this input selects the AD7899.
FL0
Flag zero. This logic input is connected to the
CONVST input of the AD7899 via LK7. A low
to high transition on this input puts all the track/
holds into their hold mode and starts conversion
on the selected channels. In addition the state of
the channel sequence selection is also latched on
the rising edge of this input
IRQ2
Interrupt Request 2. This is a logic output and is
connected to the BUSY logic output on the
AD7899. This output will go high on the rising
edge of CONVST and will return low when
conversion is completed on all selected channels.
DGND
Digital Ground. These lines are connected to the
digital ground plane on the evaluation board. It
allows the user to provide the digital supply via
the connector along with the other digital signals.
AGND Analog Ground. These lines are connected to the
analog ground plane on the evaluation board.
AV_DD
+12V
Analog +5V Supply. These lines are connected to
the V_DD supply line on the board via LK4.
+12V Supply. This line is connected to the +12V
supply line on the board via LK3.
-12V
-12V Supply. This line is connected to the -12V
supply line on the board via LK5.
Table II. 96-Way Connector Pin Functions.
ROW a
1
2
3
SCLK1
4
DGND
5
6
7
8
9
RD
10
11
12 DGND
13
14
15
16 DGND
17 FL0
18 D12
19
20 DGND
21 AGND
22 AGND
23 AGND
24 AGND
25 AGND
26 AGND
27
28
29 AGND
30 -12V
31
32 AVDD
RowB
FL1
D0
D1
DGND
D2
D3
D4
D5
D6
D7
DGND
D8
D9
D10
DGND
D11
D13
DGND
AGND
AGND
AGND
AGND
AGND
AGND
AGND
AGND
AGND
AGND
AVDD
RowC
SCLK1
DGND
WR
CS
DGND
DGND
IRQ2
DGND
AGND
AGND
AGND
AGND
AGND
AGND
AGND
+12V
AVDD
Note : The unused pins of the 96-way connector are not shown.
–4–
REV. 0