1300 Henley Court
Pullman, WA 99163
509.334.6306
www.digilentinc.com
PmodDA4™ Reference Manual
Revised May 24, 2016
This manual applies to the PmodDA4 rev. B
Overview
The Digilent PmodDA4 is an octal, 12-bit digital-to-analog converter module.
Features include:
Eight channel, 12-bit DAC
Capable of eight simultaneous outputs
High-speed DSP compatible
Power-down function capability
Low power consumption
Small PCB size for flexible designs 1.2“ × 0.8” (3.0 cm × 2.0
cm)
6-pin Pmod connector with SPI interface
Follows Digilent Interface Specification Type 2
Example code available in resource center
The PmodDA4.
1
Functional Description
The PmodDA4 utilizes Analog Devices AD5628 to provide a signal DAC capable of 8 simultaneous output channels.
With its internal reference voltage of 2.5V, a resolution of approximately 1 mV can be achieved.
2
Interfacing with the Pmod
The PmodDA4 communicates with the host board via the SPI protocol. By driving the Chip Select (CS) line to a logic
level low voltage, users may send a series of 32 bits of information with the data clocked into the appropriate
register on the falling edge of the Serial Clock (SCLK). Once the 32nd bit of information has been clocked in, the
command that was sent in the data stream is executed.
An example data stream of how the 32 bits are to be sent to the module is provided below from the AD5628
datasheet.
DOC#: 502-245
Copyright Digilent, Inc. All rights reserved.
Other product and company names mentioned may be trademarks of their respective owners.
Page 1 of 3
PmodDA4™ Reference Manual
DB31 (MSB)
X
X
Command Bits
X
X
C3
C2
C1
Address Bits
C0
A3
A2
A1
A0
Data Bits
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
DB0 (LSB)
X
X
X
X
X
X
X
X
Table 1. Example data stream from the AD5628 datasheet.
Users should note that the PmodDA4 by default attempts to use an external reference voltage. However, as there
is no external reference voltage provided on the Pmod, users must write to the register to program the chip to use
its internal reference voltage of 2.5V. The data stream required to change this is provided below:
Internal REF Register (DB0)
Action
0
1
Reference off (default)
Reference on
Table 2. Internal reference register from the AD5628 datasheet (table 10).
DB31 to DB28
DB27
DB26
DB25
DB24
X
1
0
0
0
Don't Cares
DB23
X
Command bits (C3 to C0)
DB22
X
DB21
X
DB20
X
Address bits (A3 to A0) - don't cares
DB19 to DB1
X
DB0
1/0
Don't cares
Internal REF
register
Table 3. 32-bit input shift register contents for reference set-up command from the AD5628 datasheet (table 11).
The various commands and addresses available for the on-board AD5628 can be found on page 22 of its datasheet.
2.1
Pinout Description Table
Pin
Signal
Description
1
~CS
Chip Select
2
MOSI
Master-Out-Slave-In
3
(NC)
Not Connected
4
SCLK
Serial Clock
5
GND
Power Supply Ground
6
VCC
Power Supply (3.3V/5V)
Any external power applied to the PmodDA4 must be within 2.7V and 5.5V; however, it is recommended that
Pmod is operated at 3.3V.
Copyright Digilent, Inc. All rights reserved.
Other product and company names mentioned may be trademarks of their respective owners.
Page 2 of 3
PmodDA4™ Reference Manual
3
Physical Dimensions
The pins on the pin header are spaced 100 mil apart. The PCB is 1.2 inches long on the sides parallel to the pins on
the pin header and 0.8 inches long on the sides perpendicular to the pin header.
Copyright Digilent, Inc. All rights reserved.
Other product and company names mentioned may be trademarks of their respective owners.
Page 3 of 3
很抱歉,暂时无法提供与“410-245”相匹配的价格&库存,您可以联系我们找货
免费人工找货