UG-062 Evaluation Board User Guide
Rev. 0 | Page 4 of 12
EVALUATION BOARD HARDWARE
CONNECTOR FUNCTION DESCRIPTIONS
Table 1.
Name Mnemonic Description
J6 USB interface Plug the USB cable directly from the PC into this connector. It is a type USB Mini-B socket.
J13-1 Power
Power can be supplied to the board by either the USB cable or the power connector, J13. If L5 is in Position B,
power is supplied via the USB cable. If L5 is in Position A, power is supplied from the J13-1 connector.
J13-2 AGND An external ground can be connected via the J13-2 connector.
J7-2 EXT_VREF
Connector J7-2 can be used to apply a signal to the VREF input on the AD7843/AD7873. L6 must be in
Position A for this connector to be linked to the AD7843/AD7873. If L6 is in Position B, 3.3 V is applied to
the VREF input.
J2 AUX The J2 connector can be used to apply a signal to the AUX input on the AD7843/AD7873.
J5 EXT_BAT
Connector J5 can be used to apply a signal to the VBAT input on the AD7843/AD7873. L7 must be in Position B
for this connector to be linked to the AD7843/AD7873.
J3 Touch screen
The touch screen included with the demonstration kit can be connected directly into the AD7843/AD7873
demonstration board using this connector. Connect as follows: X− to J3-1, Y+ to J3-2, X+ to J3-3, and Y− to J3-4.
J1 Touch screen
This connector can be used to connect a touch screen to the AD7843/AD7873. Connect as follows:
X− to J1-1, Y+ to J1-2, X+ to J1-3, and Y− to J1-4.
LINK FUNCTION DESCRIPTIONS
Table 2.
Name Mnemonic
Default
Position Description
L1 X+ A
This jumper selects the X+ input on the AD7843/AD7873. If the jumper is in Position A, the X+ input
comes from the J1-3 or J3-3 touch screen connectors.
L2 Y+ A
This jumper selects the Y+ input on the AD7843/AD7873. If the jumper is in Position A, the Y+ input
comes from the J1-2 or J3-2 touch screen connectors.
L3 X− A
This jumper selects the X− input on the AD7843/AD7873. If the jumper is in Position A, the X− input
comes from the J1-1 or J3-1 touch screen connectors.
L4 Y− A
This jumper selects the Y− input on the AD7843/AD7873. If the jumper is in Position A, the Y− input
comes from the J1-4 or J3-4 touch screen connectors.
L5 Input power B
This jumper selects the input power for the evaluation board. If the jumper is in Position A, power
for the board must be supplied through the J13-1connector. If the link is in Position B, the USB
connection supplies the power for the board.
L6 REF input A
This jumper selects the input signal to the reference input on the AD7843/AD7873. If the jumper is
in Position A, REF is connected to Pin 2 of the J7 (J7-2) connector. An input voltage can then be
connected to J7-1. If the link is in Position B, REF is connected to 3.3 V.
L7 BAT input A
This jumper selects the input signal to the VBAT input on the AD7843/AD7873. If the jumper is in
Position B, VBAT is connected to the J5 connector. An input voltage can then be connected to J5. If
the link is in Position A, VBAT is connected to a variable resistor, R9. The user can vary R9 to change
the input voltage on the V
BAT
pin. The maximum resistance of R9 is 10 kΩ.
INDICATOR LED DESCRIPTIONS
Table 3.
Name Mnemonic Description
D1
PENIRQ
This LED indicates when lit (green) that the
PENIRQ
interrupt is active on the AD7843/AD7873.
