General Description The TC1275/TC1276/TC1277 are cost-effective system supervisor circuits designed to monitor VCC in digital systems and provide a reset signal to the host processor when necessary. No external components are required. The reset output is driven active within 20 μs of VCC falling through the reset voltage threshold. RESET is maintained active for a minimum of 100 ms after VCC rises above the reset threshold. The TC1277 has an active-high RESET output while the TC1275 and TC1276 have an active-low RESET output. TC1275 and TC1277 each have a complimentary output while the TC1276 has an open drain output. The output of the TC1275 and TC1276 is valid down to VCC = 1.2V. The TC1277 is valid down to VCC = 1.8V. All three devices are available in a 3-Pin SOT-23 package. The TC1275/TC1276/TC1277 devices are optimized to reject fast transient glitches on the VCC line.