Datasheet

www.ti.com External Buffer
5 External Buffer
The ADS7924 device has the option of selecting an external buffer going from MUXOUT to ADCIN. An
OPA363 can be used as a buffer and is selected through the configuration of J11. Connecting pins 1 and
2 together will bypass the external buffer, while connecting pins 1 and 3 and pins 2 and 4 will complete
the circuit for the buffer. Figure 2 shows jumper J11 as it appears on the EVM in its default position, using
the buffer.
Figure 2. Jumper J11
6 EVM Operation
This section provides information on the analog input, digital control, and general operating conditions of
the ADS7924EVM.
6.1 Analog Input
Each of the analog input sources can be applied directly to J1 (top or bottom side) or through
signal-conditioning modules available for the modular EVM system. Terminal block J4 is connected in
parallel with the analog signal connections to J1.
6.2 Digital Control
The digital control signals can be applied directly to J3 (top or bottom side). The modular ADS7924EVM
can also be connected directly to a DSP or microcontroller interface board, such as the 5-6K Interface
EVM or HPA-MCU Interface boards available from Texas Instruments, or the MMB3 if purchased as part
of the ADS7924EVM-PDK. For a list of compatible interface and/or accessory boards for the EVM or the
ADS7924, see the relevant product folder on the TI web site.
7
SBAU173–June 2010 ADS7924EVM and ADS7924EVM-PDK User's Guide
Copyright © 2010, Texas Instruments Incorporated