≡ Menu

Measuring 7.5 by 5.0 by 0.8 inches, the P300 is designed for applications that requires massive number of I/O lines.

The P300 can provide up to 300 I/O lines and can be used in a large control system to drive lights or solenoids and to monitor switches.

These expansion controllers are generally driven by one of the Engine controllers (ranging from the A-Engine to the 586-Engine), providing easy C-programmable access to the various peripheral components.

Eleven PPI chips (82C55) provide a total of 264 I/O lines. Of these, 240 lines are buffered by solenoid drivers. The high-voltage I/O lines are hardware configurable as inputs or outputs. The inputs can take up to 35V DC. The outputs are capable of sinking 350 mA at 50V per line, and they can directly drive solenoids, relays, or lights.

Two channels of RS-232 drivers, one optional RS-485 driver, and a 5V linear regulator are on-board. These can be used to power the P300 as well as any processor board installed upon it. With the default 5V linear regulator, the P300 requires 8.5V to 12V DC power supply.

An optional switching regulator can be installed to provide high efficiency regulation without generating heat for up to 35V DC power input, accommodating this controller for industrial environments.

The P100 is a smaller and less expensive controller similar to the P300. It is still an excellent controller for applications requiring large numbers of digital I/O. It also includes 2 quadrature decoders as well as 7 solenoid drivers, making it versatile enough for other applications such as mobile control.

Product Comparison
TERN is also offering a more flexible (but with fewer I/O channels) version of these expansion boards designed for use with 16-bit Engine controllers. The P50 offers high-speed parallel ADC/DAC with onboard signal conditioning, opto-coupler inputs, an Ethernet connection, as well as a range of other features.

P300 Specs:

  • Measures 7.5×5.0x0.8 inches
  • Power: < 200 mA at 9V-12V
  • 264 I/O lines includes 240 solenoid drivers
  • Temperature: -40 to +80 Celsius
  • LCD and keypad interface
  • 240 high voltage I/Os, configurable as input or output
  • 5V switching regulator, RS-232/485 driver
  • 2 RS-232, 1 RS-485 drivers

P100 Specs:

  • Measures 4.4×2.9×0.5 inches
  • 24×4 TTL I/O lines from 4 PPIs
  • 7 solenoid drivers
  • 2 quadrature decoders (HP2020) for motion control
  • 5V switching regulator, RS-232/485 drivers
  • 2 RS-232, 1 RS-485 drivers

Similar expansion boards: P50, PC-Co
Supported controllers: i386-Engine, A-Engine, 586-Engine


  • Includes 2 RS-232 drivers
  • 1 RS-485 drivers
  • 7 solenoid drivers
  • 24×4 TTL I/Os


  • Includes 2 RS-232 drivers
  • 264 digital I/Os supporting 240 solenoid drivers
  • Does not include add-on options or controller.


Add-on Options

No.Item Price
1Switching regulator $20
2Quadrature decoder (HP2020) up to 2 $30 each

Related Products