Custom  Adjustable Power supply / Power regulator board.


The EID78ADJ board is designed to convert 26-30 Volts AC (half wave) or DC input voltage to stabilize custom adjustable DC voltage output (1.25 to 24V DC). If used properly, it will eliminate the need for expensive industrial power supplies, which would otherwise be needed to carry out the same task.


EID78ADJ is easy to install, setup and operate. If you want to  professionally power your HVAC products, EID78ADJ offers the features you need. Mounted easily via one 0.125" mounting holes. or directly solder to your board through 3 pins.


The board is designed to attenuate, filter and regulate 26-30V DC or AC to stable custom V DC.


Will replace any MC78XX/LM78XX/SG78XX regulator.


For our line of transformers click Here


Pins left to right: 


1) Input, 


2) Ground (common)


3) Output



Shown above with adjustable regulate output 1.25V to 24V DC. On the right board configured for extra low current, on left for high current.


Drop-in replacement for MC78XX, LM78XX and SG78XX voltage regulators


Linear regulators for 90% and up efficiency


Integrated capacitors no external components needed


See also our fixed output version





EID78XYZ Features


  • Up to 250mA output.

  • +/-3% voltage stability.

  • Generally powered from any power source, AC or DC, that is larger then 2 volts of the desired output voltage.

  • Also, designed to operate from two or three 12VDC car batteries


  • Input voltage                           26-30V AC or DC

  • Relative Output voltage stability  +/-3%

  • Output current                         Up to 250mA, higher output current models are available.

  • PCB material                             FR4

  • Output Voltage                         Custom from 1.25V to 24V DC set via multi-turn trimmer

  • Max power consumption             7W

  • Storage temperature                 40 - 70   [F]

  • Operating temperature               32 - 140 [F] (0 to 60C) @ 95% RH

  • Low board DC voltage                36[V] max

  • Size                                        1.25" long by 0.75" wide, 0.125" mounting hole (for 4-40 screw)

  • Manufactured                           100% in USA



* Prices, P#, SKU# and colors are subject to change without notice. 




EID78XADJ Custom Adjustable Power supply module



EID78XADJ Custom Adjustable Power supply module, low current configuration.