Analog Interface; Pinout Of J1 - Texas Instruments DAC7811EVM User Manual

Analog Interface

characteristics. This EVM is compatible with the Texas Instruments 5-6K Interface Board (SLAU104), the
HPA-MCU Interface Board (SLAU106) and additional 3
Board from SoftBaugh, Inc. (www.softbaugh.com). Field programmable gate array (FPGA) users may also
use the DAC7811EVM with a variety of Xilinx FPGAs by obtaining the Texas Instruments Analog Adapter
Kit (part number ADS-TI-AD-DAU) from Avnet Electronics Marketing.
2 Analog Interface
For maximum flexibility, the DAC7811 EVM is designed for easy interfacing to multiple analog sources.
Table 1 provides the pinout of connector J1. Samtec part numbers SSW-110-22-F-D-VS-K and
TSM-110-01-T-DV-P provide a convenient 10-pin, dual-row header/socket combination at J1. This
header/socket provides access to the analog output pins of the DAC through the onboard buffer amplifier.
Consult Samtec at www.samtec.com, or call 1-800-SAMTEC-9 for a variety of mating connector options.
Pin Number
J1.2
J1.4
J1.6
J1.8
J1.10
J1.12
J1.14
J1.16
J1.18
J1.20
J1.15
J1.1–J1.19 (odd)
2.1 EVM Output Voltage
Switch SW1 provides a means to allow unipolar or bipolar output operation of the DAC7811EVM. When
the slide switch is to the right, the output voltage on J1.4 and TP2 is ±VREF. If the onboard reference is
used, this means that the output voltage is –10 Vdc to +10 Vdc. When the switch is to the left, the output
voltage from the buffer is dependent on the position of W3. With a negative reference applied (default
condition, W3 pins 1-2 shorted), the voltage output from the buffer is 0 V to +10 Vdc. If W3 is located on
pins 2-3, a positive 10-V reference is applied to the DAC7811, and the voltage output from the buffer is 0
V to –10 Vdc.
For a wider dynamic output range, the EVM can be configured to use an external reference by removing
the shunt at W3 and applying an external source to W3 pin 2 (center pin). In this case, an external
reference of ±15 V may be applied to the DAC7811. For best performance, the external reference must be
supplied by a clean ac or dc source.
2 DAC7811EVM
Table 1. Pinout of J1
Signal
Iout DAC current output – remove W1 and install R12 using a 0-Ω resistor
Vout Option Pins 4-18 (even) are used with W2. W2 is a dual-row, 7-pin header with a shunt jumper used
to apply the output voltage from U2 on various pins of J1. This combination is provided to
Vout Option
allow the EVM user the option of daisy-chaining up to a maximum of seven EVMs.
Vout Option
Vout Option
Vout Option
Vout Option
Vout Option
REF(-) Unused
REF(+) Unused
Vcom Unused
AGND Analog ground connections (except J1.15)
rd
party boards such as the HPA449 Demonstration
Description
www.ti.com
SLAU163 – September 2005