16b, 10Hz sensor ADC
Overview
STAR3000 is designed to digitize a differential analog signal, with an SNR of >96dB over a signal bandwidth of 10Hz, with a nominal sampling rate of 32.768kHz. The ADC is designed in a 0.18µm CMOS Silterra process and designed to run off a 1.8V (±10%) supply, where the ADC consumes 30uA of current. The ADC uses an enhanced input stage to allows the ADC to sample voltages as low as -0.25V. A second-order architecture Delta-Sigma architecture is used to achieve an SQNR of > 100dB over a 10Hz bandwidth. Chopping is used in all key opamps to minimize 1/f noise in the ADC output.
Key Features
- Programmable input range
- Enhanced input stage enables ADC to quantize inputs between -0.25 and +0.25V
- Low 1/f noise enabled by using chopped opamps in key parts of circuit
- Good linearity as ADC uses a 1-bit quantizer
- Low current consumption (30uA)
- 16-bit thermal noise-floor over 10Hz input bandwidth
- Test-bus access to internal key internal nodes
- Digitally enhanced ADC stability
- Optional digital CIC filter available
- Optional I2C/SPI digital interface available
- Optional within 1% factory calibrated internal 32.768kHz oscillator available
- Optional LDO to generate 1.8V from 3.3V
- -40°C to 85°C operating range
- 0.18um CMOS Silterra Process
- Designed to operate at 1.8V ±10%
- Macro area: 580um x 450um
- .GDS ready
- Silicon verified
Block Diagram
Applications
- Battery meter/Gas gauge
- Sensor applications
- Power applications
- Base-band digitization for DC type signals with slowly varying bandwidth
- On-chip test-bus digitization
Deliverables
- .gds layout database
- .lib liberty timing models
- .lef layout exchange format files
- Extensive documentation
- Customer support/integration package
- Design usage training
- Schematics available
- Secured online portal