Patent ID: 11870450
Assignee: AMBARELLA INTERNATIONAL LP
Field: Basic communication processes (Electrical engineering)
Classification: CPC H | IPC H

Claim 2:
3. The apparatus according to claim 2, wherein said voltage controlled oscillator comprises:
a third circuit having a first input connected to a supply voltage and a first output presenting a regulated supply voltage to a node, wherein said third circuit is configured to generate said regulated supply voltage at said node in response to said supply voltage;
a fourth circuit connected to said node and configured to generate a reference signal and a bias signal in response to a reference current; and
a fifth circuit having a second input connected to said node, a third input receiving said reference signal from said fourth circuit, a fourth input receiving said bias signal from said fourth circuit, a fifth input receiving said second input signal, and a second output presenting a control current to a ring oscillator, wherein
(i) sit said third circuit is configured to filter out noise of said supply voltage,
(ii) said fourth circuit forms a current mirror with said fifth circuit,
(iii) a transistor connected to said fourth circuit sets said reference current of said fourth circuit based on said voltage level of said first input signal,
(iv) said fifth circuit is configured to provide a programmable current ratio for said current mirror based on said value of said second input signal, and
(v) said voltage level of said first input signal is set to about half of said regulated supply voltage when said second circuit performs said calibration operation to select said value of said second input signal.