WMS7201010S WINBOND [Winbond], WMS7201010S Datasheet - Page 11

• Manufacturer Part Number: WMS7201010S
• Description: 256-TAP NON-VOLATILE DIGITAL POTENTIOMETER
• Manufacturer: WINBOND [Winbond]

CLK
SDI
CS
A3 and A2 are the address bits that decide which NVMEM memory to be accessed, as shown in the
table below.
D7-D0 are the data values to be loaded into the Tap Register to set the wiper position, while D8 is
used to set the output mode. D8 has to be loaded into the NVMEM0~3 first and then the “Load Tap
Register” command (#6) has be executed to load D8 into the output-selection MUX to set the output
mode. D8=0 sets the output to Buffer Off mode while D8=1 sets to Buffer On mode.
Note:
•
•
A multiple of 24 bits must always be sent or the
command will not be valid
Bits marked ‘x’ are don’t care bits.
C3
`
1 2 3 4 5 6 7 8 9 1
C2 C1 C0 A3 A2 A1 A0 x
CS is taken LOW
before command
starts
[A1 A0]
Channel
TABLE 3 – A1 AND A0 ADDRESS BIT DECODE TABLE
TABLE 4 – A3 AND A2 ADDRESS BIT DECODE TABLE
[A3 A2]
NVMEM
FIGURE 5 – SPI COMMAND WAVEFORMS
[0 0]
0
0
x x x
1
1
[0 0]
0
1
2
- 11 -
1
3
x x
[0 1]
1
[0 1]
1
1
4
1
5
x D8 D7 D6 D5 D4 D3 D2 D1 D0
1
6
[1 0]
2
1
7
[1 0]
2
Publication Release Date: January 2003
1
8
CS is taken HIGH
after command is
sent
[1 1]
3
1
9
2
0
[1 1]
3
2
1
2
2
WMS7201
2
3
2
4
Revision 1.1