EVM Digital Interface
3
EVM Digital Interface
Samtec part numbers SSW-110-22-F-D-VS-K and TSM-110-01-L-DV-P provide convenient 10-pin, dual-
row, header and socket combinations at P1. The header and socket provide access to the ADC digital
control pins. Consult Samtec at
or call 1-800-SAMTEC-9 for a variety of mating
connector options.
summarizes the pinouts for digital interface J2.
Table 2. J2: Serial Interface Header
Pin Number
Signal
Description
Chip-select input that can be used as a convert
J2.1
CS or CONVST
start
J2.3
SCLK
Serial clock input
Input used as convert start by the MMB0
J2.7
CS or CONVST
motherboard
J2:13
SDO or MISO
SDO or MISO output
Interrupt output for detecting end of conversion with
J2.15
INT
BUSY bit
Direct connection to the convert start pin if JP3 is
J2.17
CONVST
installed
J2.4, J2.10, and J2.18
GND
Grounded pins
I
2
C bus; used only to program the U4 EEPROM on
J2.16, J2.20
I
2
C bus
the EVM board
J2.2, J2.5-6, J2.8-9,
J2.11-12, J2.14, and
Unused
Unused
J2:19
3.1
Serial Interface (SPI)
The ADS8339 ADC uses SPI serial communication to send conversion results to the MMB0 motherboard,
and subsequently, to a computer using universal serial bus (USB). The serial clock signal (SCLK) is
created by the MMB0 motherboard as the SPI host, with a frequency that is programmable up 25-MHz to
obtain the maximum sampling rate of 250-kSPS.
3.2
I
2
C Bus for Onboard EEPROM
The ADS8339EVM has an I
2
C bus used by the MMB0 motherboard to communicate with the onboard
EEPROM. The bus is not used in any form by the ADS8339 converter.
6
ADS8339EVM-PDK
SBAU233A – October 2014 – Revised November 2015
Copyright © 2014–2015, Texas Instruments Incorporated
