Texas Instruments ADS7861 EVM, User Manual, Page: 17 / 20

5-1
EVM Operation
Apply a current limited (150 mA max) 5-V dc source to J3 and J4 prior to
connecting the analog input signals and digital control signals.
The analog input source can be applied directly to header/socket J1 (top or
bottom side) or through optional amplifier and signal conditioning modules.
The analog input level should not exceed 5 V
p–p
.The analog input range is
from –VREF to VREF (0 V to 5 Vdc) centered at 2.5 V.
The digital control signals can be applied directly to header/socket J2 (top or
bottom side). The ADS7861/8361 EVM can also be connected directly to a
DSP interface board. Consult the ADS7861 and ADS8361 product folders for
a complete list of DSP interface cards and optional analog interface modules.
Jumper W2 is provided to allow separation of the convert start (CONVST) and
read (RD) signals. The factory default condition for the EVM is to place a shunt
jumper between pin 1 and pin 2 of W2. This combines signals RD and
CONVST, which are applied to the ADC via pin J2.7. When W2 is moved to pin
2 and pin 3, the RD signal is applied via pin J2.7 while CONVST is applied to
pin J2.17.
Header J5 is a means to access the M0, M1, and A1 control lines as well as
the OUTB serial data. Shunt jumpers are placed on pins 1 and 2, 3 and 4, and
5 and 6 of J5, which defaults M0, M1, and A0 to logic low levels. Removing the
jumpers allows these lines to go to logic high levels through the associated
pullup resistors R12, R13, and R14. In the factory default conditions, the ADC
is converting the A0 and B0 inputs, placing AOUT serial data on pin J2.13, and
BOUT serial data on pin J5.7.
Chapter 5