ADS1191 - Complete Low Power Integrated Analog Front End for ECG Applications

The ADS1191/2 are a family of multichannel, simultaneous sampling, 16-bit, delta-sigma (ΔΣ) analog-to-digital converters (ADCs) with a built-in programmable gain amplifier (PGA), internal reference, and an onboard oscillator.

The ADS1191/2 incorporate all of the features that are commonly required in portable, low-power medical electrocardiogram (ECG), sports, and fitness applications.

With its high levels of integration and exceptional performance, the ADS1191/2 family enables the creation of scalable medical instrumentation systems at significantly reduced size, power, and overall cost.

The ADS1191/2 have a flexible input multiplexer per channel that can be independently connected to the internally-generated signals for test, temperature, and lead-off detection. Additionally, any configuration of input channels can be selected for derivation of the right leg drive (RLD) output signal. The ADS1191/2 operate at data rates up to 8 kSPS. Lead-off detection can be implemented internal to the device, using the device internal excitation current sink/source.

The devices are packaged in a 5-mm × 5-mm, 32-pin thin quad flat pack (TQFP). Operating temperature is specified from –40°C to +85°C.

• Two Low-Noise PGAs and
  Two High-Resolution ADCs (ADS1192)
• Low Power: 335 µW/channel
• Input-Referred Noise: 24 µV_PP
  (150-Hz BW, G = 6)
• Input Bias Current: 1 nA
• Data Rate: 125 SPS to 8 kSPS
• CMRR: –95 dB
• Programmable Gain: 1, 2, 3, 4, 6, 8, or 12
• Supplies: Unipolar or Bipolar
  • Analog: 2.7 V to 5.25 V
  • Digital: 1.7 V to 3.6 V
• Built-In Right Leg Drive Amplifier, Lead-Off Detection, Test Signals
• Built-In Oscillator and Reference
• Flexible Power-Down, Standby Mode
• SPI™-Compatible Serial Interface
• Operating Temperature Range: –40°C to +85°C