MEMORY PROTECTOR

摘要

Cartridge (1) contains memory (40a-40h) and a back-up battery (13). Terminals (5a-5i) of the cartridge (1) plug into termnals (7a-7i) of a host machine (3). Positive deactivation of the write control is achieved by both the base and emitter of a bipolar transistor (52) being deactivated when the cartridge (1) is unplugged. Battery voltage then appears at read/write control line (64) through resistor (56) connected to the collector of the transistor (52). This brings the control line (64) to the read status and positively protects data in memory (40a-40h) against transient signals, which may occur especially during plug in when the host (3) is activated, or from electrostatic charges.