AD7879-1ACPZ-500R7 Analog Devices Inc, AD7879-1ACPZ-500R7 Datasheet - Page 23

• Manufacturer Part Number: AD7879-1ACPZ-500R7
• Description: Touch Screen Controller
• Manufacturer: Analog Devices Inc
• Type: Resistiver

Specifications of AD7879-1ACPZ-500R7

• Touch Panel Interface: 4-Wire
• Number Of Inputs/keys: 1 TSC
• Resolution (bits): 12 b
• Data Interface: I²C, Serial
• Data Rate/sampling Rate (sps, Bps): 105k
• Voltage Reference: External
• Voltage - Supply: 1.6 V ~ 3.6 V
• Current - Supply: 10nA
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 16-LFCSP-VQ
• Voltage Supply Source: Single Supply
• Sampling Rate (per Second): 105k
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: AD7879-1ACPZ-500R7TR

Table 13. Control Register 2
Address
0x02
1
This delay occurs before conversion of the X and Y coordinate channels (including Z1 and Z2) to allow for screen settling and before the first conversion to allow the
ADC to power up.
Bit Name
PM[1:0]
GPIO EN
GPIO DAT
GPIO DIR
GPIO POL
SER/DFR
AVG[1:0]
MED[1:0]
SW/RST
FCD[3:0]
Data Bit
[15:14]
13
12
11
10
9
[8:7]
[6:5]
4
[3:0]
Description
ADC power management.
00 = full shutdown; the ADC, oscillator, bias, and temperature sensor are all powered down.
01 = analog blocks to be powered down depend on the ADC mode.
If ADC mode is master mode, the ADC, oscillator, bias, and temperature sensor are powered
down and must wake up when the user touches the screen.
If ADC mode is slave mode, the ADC and temperature sensor are powered down when not
being used. They wake up automatically when required. The oscillator and bias are powered
up because they are needed to measure time. This also applies to the single-conversion mode.
10 = ADC, bias, and oscillator are powered up continuously, irrespective of ADC mode.
11 = same as 01.
GPIO enable.
0 = AUX/VBAT channel active.
1 = GPIO enabled on AUX/VBAT/GPIO pin.
GPIO data bit.
GPIO direction.
0 = output.
1 = input.
GPIO polarity.
0 = GPIO pin is active low.
1 = GPIO pin is active high.
Selects normal (single-ended) or ratiometric (differential) conversion.
0 = ratiometric (differential).
1 = normal (single-ended).
ADC averaging.
00 = 2 middle values averaged (one measurement when median filter is disabled).
01 = 4 middle values averaged.
10 = 8 middle values averaged.
11 = 16 values averaged.
Median filter size.
00 = median filter disabled.
01 = 4 measurements.
10 = 8 measurements.
11 = 16 measurements.
Software reset; digital logic is reset when this bit is set.
ADC first conversion delay.
Starts at 128 µs (default) and continues to 4.096 ms in steps of 128 µs (see Table 22).
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1
AD7879/AD7889
Default
Value
0x4040