Pmod SSR Reference Manual

The Digilent Pmod SSR (Revision B) is a solid state relay that features IXYS' CPC1908J. The Pmod SSR uses a switch controlled by a single GPIO pin and is rated to block up to 48 Volts and switch up to 6 Arms continuous current.

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  • 0-48 V blocking voltage
  • Can switch up to 6 Arms continous current
  • 2500 V input/output isolation
  • Low on resistance with fast turn on/off
  • Onboard LED to indicate on/off state
  • Onboard terminal block for easy wire connection
  • Small PCB size for flexible designs 1.7“ × 0.8” (4.3 cm × 2.0 cm)
  • 6-pin Pmod Connector with GPIO interface
  • Follows the Digilent Pmod Interface Specification Type 1
  • Libraries and example code available in resource center

Functional Description

The Pmod SSR uses a single GPIO pin to establish a connection between two terminals.


Parameter Value Units
Maximum Blocking Voltage 48 VP
Maximum Peak Current (t⇐10ms) 25 AP
Maximum Continuous Current (25C Ambient, 400 LFPM airflow) 6.2 Arms / ADC
Maximum Continuous Current (25C Ambient, no airflow) 3.8 Arms / ADC
Parameter Min Typical Max Units
On-Resistance - 0.09 0.3 Ω
Turn-On Switching Speed - 16 20 ms
Turn-Off Switching Speed - 0.17 5 ms
Input Control Current for Activation - - 10 mA
Input Control Current for Deactivation 0.6 - - mA

Interfacing with the Pmod

The Pmod SSR communicates with the host board via a GPIO pin. To open the relay, the ON pin must be driven to a logic high state. To close the relay, the ON pin must be driven to a logic low state.

Pinout Description Table

Pin Signal Description
1 ON Switch Control
2 NC Not Connected
3 NC Not Connected
4 NC Not Connected
5 GND Power Supply Ground
6 VCC Power Supply (3.3/5 V)

Physical Dimensions

The pins on the pin header are spaced 100 mil apart. The PCB is 1.7 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. The overall height of the Pmod including the heat sink, PCB, and components on the underside of the PCB is 0.75 inches.

Additional Information

The schematics of the Pmod SSR are available here. Additional information about the Solid State Relay itself including switching speeds can be found on it's datasheet here.

Example code demonstrating how to use the Pmod SSR can be found at the Pmod SSR Resource Center.

If you have any questions or comments about the Pmod SSR, feel free to post them under the appropriate section (“Add-on Boards”) of the Digilent Forum.