Wireless Biometric Monitor
ASIC Success Story
Application
Wireless telemetry systems can monitor a variety of biometric parameters without the need for cumbersome wires to be connected between the patient and the monitor.
Typical parameters of interest include pressure, temperature, ECG, EMG, EEG and EOG data.
CSS partnered with a leading manufacturer of advanced biometric monitoring devices to create an ultra-low power transmitter ASIC for this wireless system that allows untethered data collection.
Custom Solution from CSS
This ASIC combines a low-power 555 timer with a 6-channel, low-noise amplifier. It is used to monitor 6 biometric parameters (EEG, ECG or EMG).
A p-channel power FET switches the battery to provide an ultra-low power “Sleep” mode.
The 555-timer circuit generates timing control clocks and an FM signal for the antenna. An internal voltage multiplier provides +20V allowing direct drive of the antenna.
An integrated EEPROM provides storage for a serial number, calibration and configuration data.
Key Features
- Low Voltage Supply voltage = 1.40V to 1.55V
- Low Power – Active current < 10uA, Sleep current < 50nA)
- 6 Independent Low-Noise Amplifier Channels
- 4 Gain settings (10, 20, 50, 100)
- 4 Bandwidth settings (100 to 400 KHz)
- Internal Nonvolatile Memory (EEPROM)
- 128 bits, organized 4×32
- Stores configuration & trim settings
- Internal Voltage Multiplier and High Voltage Driver
- +20V supplied by internal charge pump from 1.40V battery
- High voltage output drives antenna from 0V to +20V