Power failure alarm circuit and device

The utility model provides a power failure alarm circuit and device, and relates to the field of alarm devices. The circuit comprises a first power supply module, a second power supply module, a single-chip microcomputer module, a relay module and a GSM module. The input ends of the first power supply module and the second power supply module are both used for being connected with an external alternating current power supply, the output end of the first power supply module is connected with the input end of the single-chip microcomputer module, the output end of the first power supply module is further connected with the coil end of the relay module, and the output end of the single-chip microcomputer module is connected with the coil end of the relay module. The contact end of the relay module is connected with the input end of the GSM module, and the output end of the second power supply module is connected with the power supply input end of the GSM module. By optimizing the circuit structure, the alarm ran