Smart Signal Capture AFE

AIStorm’s AIS339 Chameleon is an AFE designed to solve the noise and connectivity issues of real-world sensor interface applications at the lowest power and in the smallest footprint possible.

Chameleon's Revolutionary Capabilities

The AIS339 Chameleon is an AFE designed to enable signal capture in difficult real world environments. Baseline capture, common mode accelerated recapture, noise rejection, nuisance signal nulling, multi-order analog filtering, and an up to 6th order almost all pass (Bessel) with mHz bandpass low end corner are example capabilities. To accomplish this the AIS339 includes: i) five input channels and a single reference channel; ii) a programmable gain amplifier (PGA); iii) differential voltage input or transconductor current mode input; iv) a high common mode rejection driver; v) a fast programmable local loop to allow fast capture and recapture of the common mode; vi) a sample and hold circuit allowing fast recovery from events which move the baseline; viii) an up to 6th order ]high order programmable filter response; ix) a buffered differential voltage input between the negative terminals of the instrumentation amplifier to null nuisance signals; x) analog or ADC outputs; xi) an optional two terminal common mode driver; xii) amplifier offset and shift registers. Between the amplifier and the ADC the AIS339 compares to sigma delta solutions with an ENOB of 18 bits but requires substantially less current. The AIS339 is capable of nyquist rate sampling between multiple different sensors. Sample & Hold and fast drift recovery circuitry is provided to remember each sensor’s common mode and return to it when a channel is selected. Also included is a precision on chip analog reference and charge pump to maximize the input common mode range. The AIS339 will operate with a supply voltage as low as 2.7V up to 3.6V and is available in a 5×5 48-pin TQFN package.

Key Features
Offers Multiple Systems to Ease Capture of Sensor Data
Allows Closed Loop DSP Around INA
6 Input (5xMultiplexer, One Ref Channel)
Linear Dimensions’ proprietary PEAL Signal Processing
Low Noise INA with Digitally Programmed AGC
Extremely High CMRR
SPI Interface
Charge Pump to Maintain Input Range
Precision Analog Reference
10-bit ADC with Separate Enable/Fast Wakeup
Multichannel Sensor and Stimulus Subsystem
High Order Filter
150uV Maximum Offset Voltage
170uA Supply Current

Optical PPG (Pulse) · Electrical (ECG) Sensing · Heart Rate · Heart Rate Variability (HRV) · Real-Time Waveform Stream · Vibration Monitoring · Audio Monitoring

Evaluation Platforms

Chameleon Evaluation Board


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