SymTech Labs' Peak & Hold Fuel Injector Driver (PH Driver) Board efficiently drives low impedance, or "peak and hold" fuel injectors. Low impedance fuel injectors are preferred by automotive designers and enthusiasts over the lower quality high impedance, or "saturated" fuel injectors. The SymTech Labs PH Driver is the only way to control these injectors to meet your engine's demanding fueling needs.

Designed for use with MegaSquirt EMS systems, the SymTech Labs PH Driver can be used to supplant the outdated injector drivers on either v2.2 or v3.0 boards. Either inline injectors resistors or a SymTech Labs PH Driver must be installed in order to use low impedance fuel injectors with a v2.2 board or an MS1 processor and the MS1/Extra High-Resolution (HR) firmware. Unlike inline resistors, the PH Driver uses a specialized network of chips with peak and hold technology to quickly and precisely control low impedance fuel injectors.

The PH Driver offers four independent channels, one for each fuel injector, perfect for use with sequential injection and MS2 with the MS2/Extra firmware, or MS3. For applications requiring more than four fuel injectors, multiple boards can be installed.

There are no tricky PWM settings to calibrate, since the onboard chips limit current draw through each injector on the fly. The PH Driver compensates for low voltage conditions (cold weather, startup, etc.), and even eliminates the radio frequency interference (RFI) characteristic of the standard MegaSquirt fuel injector drivers. The PH Driver is optimized for use with 4A peak and 1A hold low impedance fuel injectors. The board comes fully assembled and contains virtually all surface mount devices (SMD), which are less prone to failure due to vibration. The board is designed to fit a standard width (~4") MegaSquirt ECU enclosure.