EVAL-AD5171DBZ Analog Devices, EVAL-AD5171DBZ Datasheet - Page 16

• Manufacturer Part Number: EVAL-AD5171DBZ
• Description: Digital Potentiometer Development Tools EVALUATION BOARD I.C.
• Manufacturer: Analog Devices
• Series: AD5171r

Specifications of EVAL-AD5171DBZ

• Rohs: yes
• Product: Evaluation Boards
• Tool Is For Evaluation Of: AD5171
• Resistance: 5 kOhms/10 kOhms/50 kOhms/100 kOhms
• Operating Supply Voltage: 5.5 V
• Interface Type: I2C
• Maximum Operating Temperature: + 125 C
• Factory Pack Quantity: 1
• For Use With: Sim DAC Web Tool

AD5171
CONTROLLING THE AD5171
There are two ways of controlling the AD5171. Users can either
program the devices with computer software or employ external
I
SOFTWARE PROGRAMMING
Due to the advantage of the one-time programmable feature,
users may consider programming the device in the factory
before shipping it to the end users. Analog Devices offers device
programming software that can be implemented in the factory
on PCs running Windows 95 to Windows XP platforms. As a
result, external controllers are not required, which significantly
reduces development time.
The program is an executable file that does not require the user
to know any programming languages or programming skills. It
is easy to set up and use. Figure 32 shows the software interface.
The software can be downloaded from the
Write
The AD5171 starts at midscale after power-up prior to the OTP
programming. To increment or decrement the resistance, move
the scrollbar on the left. To write any specific values, use the bit
pattern control in the upper screen and click Run . The format
of writing data to the device is shown in Table 8. Once the
desired setting is found, click Program Permanent to blow the
internal fuse links for permanent setting. The user can also set
the programming bit pattern in the upper screen and click Run
to achieve the same result.
Table 8. SDA Write Mode Bit Format
S
Table 9. SDA Read Mode Bit Format
S
2
C controllers.
0
0
1
1
Slave Address Byte
0
1
0
Figure 32. Software Interface
Slave Address Byte
1
1
0
1
AD0
0
0
AD5171
AD0
A
T
product page.
X
1
Instruction Byte
X
A
X
Rev. D | Page 16 of 24
E1
X
X
E0
X
Read
To read the validation bits and data from the device, click Read .
The user may also set the bit pattern in the upper screen and
click Run . The format of reading data out from the device is
shown in Table 9.
DEVICE PROGRAMMING
To apply the device programming software in the factory, users
need to modify a parallel port cable and configure Pin 2, Pin 3,
Pin 15, and Pin 25 for SDA_write, SCL, SDA_read, and DGND,
respectively, for the control signals (see Figure 33). In addition,
lay out the PCB of the AD5171 with SCL and SDA pads, as
shown in Figure 34, such that pogo pins can be inserted for the
factory programming.
X
Figure 33. Parallel Port Connection: Pin 2 = SDA_write, Pin 3 = SCL,
D5
A
Figure 34. Recommended AD5171 PCB Layout
X
D4
Pin 15 = SDA_read, and Pin 25 = DGND
Data Byte
X
GND
SCL
V
D3
D5
13
25
12
24
11
23
10
22
9
21
8
20
7
19
6
18
5
17
4
16
3
15
2
14
1
DD
W
D4
Data Byte
D2
100Ω
100Ω
100Ω
R3
R2
R1
D3
WRITE
READ
SDA
B
AD0
A
D1
D2
SCL
SDA
D1
D0
D0
A
A
P
P