Mannics DC25 Power Module

The Mannics DC25 is a dc-dc converter module, which generates the negative voltage rails from the six volts provided by the battery. Pin 2 of this module provides -22.66 V, which is required to drive the VFD tube, and pin 3 provides -7 V, which feeds the main calculator IC.

The module consists of a group of closely matched transistors and a pulse transformer. Incorrect voltage levels applied through the power socket can damage this circuit.

Pin Voltage

**All the voltages are with respect to the battery negative.

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