MAX1233_08 Datasheet, PDF (20/44 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 (Write 0x0040/Read 0x8040)
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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