AD7877 Analog Devices, AD7877 Datasheet - Page 40

• Manufacturer Part Number: AD7877
• Description: Touch Screen Controller
• Manufacturer: Analog Devices

Specifications of AD7877

• Resolution (bits): 12bit
• # Chan: 9
• Sample Rate: 125kSPS
• Interface: Ser
• Analog Input Type: SE-Uni
• Ain Range: Uni (Vref),Uni 2.5V
• Adc Architecture: SAR
• Pkg Type: CSP

AD7877
Register Name: DAC Register
Write Address:
Read Address:
Default Value:
Type:
Table 21.
Bit
0
1
2
3
4
5
6
7
8
9
10
11
Register Name: Y Position
Write Address:
Read Address:
Default Value:
Type:
This register contains the 12-bit result of the measurement at
the X+ input with Y layer excited (Y position measurement).
Register Name: X Position
Write Address:
Read Address:
Default Value:
Type:
This register contains the 12-bit result of the measurement at
the Y+ input with X layer excited (X position measurement).
Name
RANGE
Not Used
V/I
PD
DAC0
DAC1
DAC2
DAC3
DAC4
DAC5
DAC6
DAC7
1110
01110
0x008
Read/write
N/A
10000
0x000
Read only
N/A
10001
0x000
Read only
Read/Write
R/W
R/W
R/W
R/W
Description
Output range of the DAC in voltage mode
0 = 0 to V
1 = 0 to V
This bit is not used
Voltage output and current output
0 = voltage
1 = current
DAC power-down
0 = DAC on
1 = DAC powered down
LSB of DAC data
Bit 1 of DAC data
Bit 2 of DAC data
Bit 3 of DAC data
Bit 4 of DAC data
Bit 5 of DAC data
Bit 6 of DAC data
MSB of DAC data
Rev. D | Page 40 of 44
CC
CC
/2
Register Name: Z2
Write Address:
Read Address:
Default Value:
Type:
This register contains the 12-bit result of the measurement at
the Y− input with excitation voltage applied to Y+ and X− (used
for touch-pressure calculation).
Register Name: AUX1
Write Address:
Read Address:
Default Value:
Type:
This register contains the 12-bit result of the measurement at
Auxiliary Input 1.
N/A
10010
0x000
Read only
N/A
10011
0x000
Read only
Data Sheet