MAX1233_05 Datasheet, PDF (20/45 Pages) Maxim Integrated Products – ±15kV ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller

±15kV ESD-Protected Touch-Screen
Controllers Include DAC and Keypad Controller
In order to read the entire first page of memory, for
example, the host processor must send the
MAX1233/MAX1234 the command 0x8000_H. The
MAX1233/MAX1234 then begin clocking out 16-bit data
starting with the X-data register. In order to write to the
second page of memory, the host processor sends the
MAX1233/MAX1234 the command 0x0040_H. The suc-
ceeding data is then written in 16-bit words beginning
with the ADC control register. Figures 10a and 10b show
a complete write and read operation, respectively,
between the processor and the MAX1233/MAX1234.
Memory Map
The MAX1233/MAX1234s’ internal memory is divided
into two pages—one for data and one for control, each
of which contains thirty-two 16-bit registers.
Control Registers
Table 3 provides a summary of all registers and bit
locations of the MAX1233/MAX1234.
ADC Control Register
The ADC measures touch position, touch pressure, bat-
tery voltage, auxiliary analog inputs, and temperature.
The ADC control register determines which input is
selected and converted. Tables 4 and 5 show the for-
mat and bit descriptions for the ADC control register.
SCLK
CS
WRITE OPERATION
DIN
D15
D15 IS READ/WRITE BIT
LOW FOR WRITE
D15–D0 COMMAND WORD
DOUT THREE-
STATE
TIMING NOT TO SCALE.
Figure 10a. Timing Diagram of Write Operation
SCLK
D0
D15
D15–D0 DATA WORD
D0
THREE-
STATE
CS
READ OPERATION
DIN
D15 D14
DOUT
THREE-STATE
D15–D0 COMMAND
WORD
D0
D15
DATA WORD
D0
D15
DATA WORD
D0
THREE-STATE
Figure 10b. Timing Diagram of Read Operation
Table 4. ADC Control Register
BIT15 BIT14 BIT13 BIT12 BIT11 BIT10 BIT9 BIT8 BIT7 BIT6 BIT5 BIT4 BIT3 BIT2 BIT1 BIT0
PENSTS ADSTS A/D3 A/D2 A/D1 A/D0 RES1 RES0 AVG1 AVG0 CNR1 CNR0 ST2 ST1 ST0 RFV
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