Pololu Isolated Solid State Relay/Switch (SPST) — 60V, 7A

A compact, silent, and long-life alternative to a mechanical relay. is an optically isolated solid-state SPST switch that lets a low-current control signal (from 2.7V to 40V) turn a high-current DC load on/off—up to 60V and 7A (absolute maximum / rated capability depends on cooling). Because the output is MOSFET-based, it avoids contact wear and arcing common in mechanical relays. :contentReference[oaicite:0]{index=0}

Optically isolated control: an opto-isolated driver galvanically isolates the control side from the load side.
Bidirectional, symmetric output: back-to-back MOSFETs make the two output terminals equivalent—use it for high-side or low-side switching.
Low loss switching: typical combined MOSFET on-resistance is ~30 mΩ when enabled.
Fast for “power switching”: max turn-on and turn-off times are 1 ms (not for high-speed signaling).
Low control current: control circuit draws up to 10 mA from VIN when enabled.

Important notes:

Not for fast PWM/signals: Pololu notes ~1 ms switching times make it unsuitable beyond a few hundred switching events per second.
Thermals matter: Pololu’s tests showed the 60V version can conduct ~7A continuously at ~25°C with no forced airflow, but your real limit depends on cooling and wiring. If switching > ~2/3 of the max continuously, monitor temperature and consider extra cooling.{index=7}
This board can get hot enough to burn you before thermal limits are reached—handle carefully.

Why/Benefits

Better than mechanical relays (in many builds)

Silent switching
No contact wear / no arcing issues typical of mechanical relays
Compact footprint: 0.8″ × 0.32″ × 0.13″

Safer mixed-voltage control

Galvanic isolation between microcontroller/control and the load
Wide control input: 2.7–40V
Up to 10 mA control draw when enabled

Technical specifications

Product	Pololu Isolated Solid State Relay/Switch, SPST, 60V, 7A
Control voltage range	2.7V to 40V (VIN and EN high)
Max control input current	10 mA (on VIN when enabled)
Load voltage	Up to 60V (absolute maximum)
Load current	Up to 7A (thermal/cooling dependent)
On-resistance	30 mΩ (typ. combined MOSFET RDS(on) when enabled)
Turn-on / Turn-off	1 ms max / 1 ms max
Size	0.8″ × 0.32″ × 0.13″
Weight	0.4 g

Pinout & power notes

VIN + GND: power the control side (2.7–40V).
EN: drive HIGH (2.7–40V) to turn the output switch ON.
2-wire option: if your EN source can provide ~10mA, EN and VIN can be tied together so one signal both powers and enables the board.
OUT terminals: connect in series with your load’s current path (either orientation; outputs are symmetric).

FAQ

Can I use it for AC mains?

This board is specified for switching up to 60V loads and uses MOSFETs arranged back-to-back for a symmetric DC switch. It’s commonly used for DC loads; for mains AC, use a mains-rated SSR/relay and follow electrical safety practices.
Can I PWM it for motor speed control?

Not ideal. Pololu notes ~1 ms switching times, making it unsuitable beyond a few hundred switching events per second.
Why does it heat up at high current?

All solid-state switches dissipate heat from on-resistance. Use thicker wiring and consider airflow/cooling when switching near the maximum current continuously.

Pololu Isolated Solid State Relay/Switch, SPST, 60V, 7A

Name: Pololu Isolated Solid State Relay/Switch, SPST, 60V, 7A
Brand: circuitrocks
SKU: POL5420
Price: 295.0 PHP
Availability: InStock