STAR5013

Description

STAR5013 is a low-jitter oscillator suitable for audio applications such as hearing-aids, and consumer audio. By measuring the oscillator frequency in the factory and using a binary search algorithm to select the desired centre frequency, the frequency can be guaranteed to be within +/- 2% over a temperature range of -10C to +55C. The oscillator uses a differential ring oscillator structure so as to maximize supply noise rejection. A level-shifter with active feedback is used to translate the low swing differential voltage from the oscillator core into a rail-to-rail CMOS level voltage output. Active feedback is used to measure and correct the duty cycle of the CMOS level output to be 50% within +/- 2%. The oscillator operates from a 0.9V regulated supply (externally regulated) so maximize supply rejection from the battery. The 65nm oscillator IP has an area of 0.075mm2

Features

• 32MHz frequency accurate to within +/- 2%

• Low-jitter performance

• Better than -100dBc a-weighted noise when used to clock a class-D audio driver

• 30uA of current

• Differential ring oscillator core structure

• CMOS level logic output with active feedback to maintain 50% duty cycle within +/- 2%

• Operates from a 0.9V regulated supply

• -10C to +55C performance range

• -10C to +70C functional range

• Digitally programmable centre frequency

• Analog testbus enables direct probing of key internal nodes suitable for DC test

• 0.075mm2 area

• 65nm TSMC process

Applications

• Hearing-Aids

• Consumer audio

• Audio Class-D clock source

• Low-jitter highly integrated systems