A Our current chip only supports dedicated emulator downloader, serial port download can do the corresponding functions, but can not meet the needs of online debugging.

A We have completed EPCM A, B and C modules with EPC chip, which can be used and debugged directly by customers.

A The chip itself is a single-lead sampling, due to the chip sampling rate up to 32K, you can use external analog channel switching to achieve multi-channel sampling applications.

A Adjusting the PGA amplification to the appropriate number of stages can effectively prevent amplifier saturation cutoff.

A The polarization resistance voltage of ECG mainly depends on the polarization voltage generated when the electrode pads are in contact with the human skin, and different materials of electrode pads will generate different voltages when they are in contact with the human skin. The generated voltage is superimposed on the ECG ECG signal, which is passed into the subsequent AFE analog front-end to be amplified and filtered. Methods to prevent the polarization voltage from being introduced into the subsequent circuit include adding isolation capacitors to the sampling front-end or adjusting the PGA amplification to effectively suppress baseline drift.

A Two-stage amplification

A ECG detection requires electrodes to form a circuit across the heart in the human body, and the signal that can be measured during the acquisition of EEG signals is actually the potential difference, where the potential difference is the difference between the active electrode and the reference electrode, and in order to get the accurate values of these parameters, we need to use the least active electrode as the reference. In order to get the accurate values of these parameters, we need to use the least active electrode as the reference, of course, there is also an ECG signal without the reference electrode, which can be done by turning off the right leg driver in our program.

A In fact, it is an indicator for the amplifier, the input reference noise is the noise energy measured at a certain frequency bandwidth, the standard for medical devices is 10 microvolts. Under the condition of frequency 0~100Hz, gain Gain= 6, it is less than 2.5uV.

A RISC-V core, existing routines; memory part (storage is 256K flash, 64 ROM, 64 RAM); communication protocols, digital interfaces (IIS, UART, SPI, IIC, etc.); analog part (built-in crystal oscillator, real-time clock RTC, timer TIMER reason, watchdog WDT, pulse width modulation).

A Power consumption is related to the application, and the power consumption of our chip is composed of AFE analog front-end power consumption, MCU power consumption, and the power consumption of the LEDs of the PPG, which is not a fixed value.EPC001 chip in the system clock 4M, ECG, PPG module are all in the low-speed clock mode, the use of serial communication, real-time acquisition of waveforms, the power consumption of the ECG2.1mA / PPG 3.6mA, respectively.