Power-on reset circuit

Abstract

Abstract PURPOSE:To stably generate a reset signal by providing a comparatively low threshold voltage and discharging a capacitor via a discharge circuit of a comparatively high resistance. CONSTITUTION:A discharge circuit 5 consists of two N-channel MOS transistors(TRs) 6, 7 having a prescribed threshold value. Moreover, a high resistance N-channel MOS TR 8 forms the discharge circuit and its threshold voltage is set to a value lower than the threshold voltage of the charging circuit 5. For example, the charging circuit 5 having a comparatively higher threshold voltage is turned off to interrupt the charging path to the capacitor 1 and the discharge circuit having a comparatively lower threshold voltage is turned off with a slight delay, then the electric charge charged in the capacitor 1 is discharged sufficiently by the discharge circuit during this time. Thus, the reset signal is generated stably.

Inventors

• 👤 Tetsushi Tanizaki
• 👤 Toshiyuki Tanigawa

Bibliographic Details