公开(公告)号：US12241920B2

公开(公告)日：2025-03-04

申请号：US17986612

申请日：2022-11-14

Applicant: Apple Inc.

Inventor： Arunvenkatesh Alagappan ,  Soheil Golara ,  Seyedeh Sedigheh Hashemi

IPC: G01R23/02 ,  G01R23/09 ,  G01R23/10 ,  H03K21/02

Abstract: An integrated circuit can include frequency monitoring circuitry. The frequency monitoring circuitry may include a voltage based frequency monitoring circuit for monitoring an input clock signal having an input clock frequency within a first set of frequencies and a coarse frequency monitoring circuit for monitoring an input clock signal having an input clock frequency within a second set of frequencies different than the first set of frequencies. The voltage based frequency monitoring circuit can be configured to generate an output voltage having a first value when the input clock frequency is greater than a reference frequency and having a second value when the input clock frequency is less than the reference frequency. The coarse frequency monitoring circuit can include a reference counter and an input clock counter that generates a count value used to compute the input clock frequency.

公开(公告)号：US20240110959A1

公开(公告)日：2024-04-04

申请号：US17986612

申请日：2022-11-14

Applicant: Apple Inc.

Inventor： Arunvenkatesh Alagappan ,  Soheil Golara ,  Seyedeh Sedigheh Hashemi

IPC: G01R23/02 ,  H03K21/02

CPC classification number: G01R23/02 ,  H03K21/02

Abstract: An integrated circuit can include frequency monitoring circuitry. The frequency monitoring circuitry may include a voltage based frequency monitoring circuit for monitoring an input clock signal having an input clock frequency within a first set of frequencies and a coarse frequency monitoring circuit for monitoring an input clock signal having an input clock frequency within a second set of frequencies different than the first set of frequencies. The voltage based frequency monitoring circuit can be configured to generate an output voltage having a first value when the input clock frequency is greater than a reference frequency and having a second value when the input clock frequency is less than the reference frequency. The coarse frequency monitoring circuit can include a reference counter and an input clock counter that generates a count value used to compute the input clock frequency.