Power And Analog Interface - Semtech SX8650 User Manual

ADVANCED COMMUNICATIONS & SENSING
J3 header gives access to the J1 or J4 touch screen connectors. The jumpers set in the left vertical row of J3 enable the
connection to J1 connector.
The jumpers set in the horizontal way of J3 enable the connection to J4 connector.
A direct connection via J3 can also be made to adapt other panel connections.
Pin Number Signal
J3(3) Y-
J3(7) X-
J3(11) Y+
J3(15) X+
J3(17-19) GND_0

2.4. Power and analog Interface

For maximum flexibility, the SX8650EVK is designed for easy interfacing to multiple analog-sources.
The board is powered from the USB. The S_V switch allows the user to test the SX8650 to 3.3V (switch to the left) or 1.85V
(switch to the right).
If the user want to test the chip with a different supply voltage then the jumper JP1 (3-4) should be removed and an
external voltage connected to JP1 (4). The SX8650 supply voltage range goes from 1.65V to 3.7V.
JP1 (18) gives access to the AUX input.
If the AUX input of the SX8650 is configured as an analog input, an arbitrary signal generator or any analog signal can be
connected on JP1(18).
If the AUX input of the SX8650 is configured to be used as a trigger for conversion, then a square wave generator or any
digital signal can be connected to JP1(18).
Revision V2.1/June 2010
©2010 Semtech Corp.
Description
4-wire touch screen Y- plate voltage supply
4-wire touch screen X- plate voltage supply
4-wire touch screen Y+ plate voltage supply
4-wire touch screen X+ plate voltage supply
Ground
Table 2: J3 pinout
Y-
X-
Y+
X+
GND
Connection through J1
Figure 1. Connection for J1 or J4 connectors
Page 4
Y-
X-
Y+
X+
GND
Connection through J4
SX8650EVK
USER GUIDE
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