Texas Instruments THS1206EVM, Руководство пользователя

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Digital Interface
2-3 Analog and Digital Interface
2.2 Digital Interface
The Modular THS1206EVM is designed for easy interfacing to multiple control
platforms. Jumper options are provided on the EVM to allow direct control over
the state of chip select pins (/CS0 and CS1) as well as the /RD pin.
Jumper W4 controls the signal applied to the active low CS0 pin. By completely
removing the shunt jumper located at W4, the CS0 pin is pulled low via a 10K
resistor R10. Used in combination with U2, an SN74AHC138 address
decoder, W4 allows the CS0 signal to be controlled by one of three different
addresses. Having the ability to select the address location of the ADC
provides the possibility of stacking additional parallel ADC or DAC boards with
the Modular THS1206EVM.
Jumpers W2 and W3 control signals applied to the RD and CS1 pins of the data
converter. Closing the jumpers allows the signals to be applied via the parallel
control connector J2. Opening the jumpers provides a logic high signal through
pull up resistors R6 and R7.
2.2.1 Parallel Control
Samtec part numbers SSW-110-22-F-D-VS-K and TSM-110-01-T-DV-P
provide a convenient ten-pin dual row header/socket combination at J2. This
header/socket provides access to the digital control pins of the EVM. Consult
Samtec at
www.samtec.com or 1-800-SAMTEC-9 for a variety of mating
connector options.
Pin Number Signal Description
J2.1 DC_CSa Daughter card chip select – active low signal used to
access the EVM
J2.3 WR DSP write strobe – active low signal used to initiate a
conversion
J2.5 RD DSP read strobe – active low signal used to access
parallel data
J2.7 EVM_A0 EVM address line 0 – used in conjunction with U2 to
control CS0
J2.9 EVM_A1 EVM address line 1 – used in conjunction with U2 to
control CS0
J2.11 EVM_A2 EVM address line 2 – used in conjunction with U2 to
control CS0
J2.13 EVM_A3 EVM address line 3 – used in conjunction with U2 to
control CS0
J2.15 EVM_A4 EVM address line 4 – not used
J2.17 TOUT DSP timer input – optional CONVCLK or CONVST
source
J2.19 INT DSP interrupt input – connects to the ADC DATA_AV
pin