PC Boards are no longer available for this circuit.Mar 9/98
The following changes were made to the first version of the Low Voltage Disconnect circuit.
A diode was added on the 12v line to the relay driver part of the circuit. This was added to prevent a short circuit condition that occurs when the battery polarity was reversed.
The capacitor on the Voltage Monitoring input was removed. It was not necessary.
The capacitors on pins 2 and 6 of the IC were specified as Tantalum type. They were found to have lower leakage current. Leakage current was found to upset the set point adjustments.
The terminal numbers on TB1 was corrected to correspond to the circuit board.
The component designations were renumbered. for the new component set.
The circuit board was revised to reflect the changes. It was relabeled PC- 420A.
Additional notes regarding the leakage of C1 and C2 were added to the construction notes.
The PCB pattern was changed to accommodate dipped radial lead tantalum capacitors for C1 and C2.