First Derivative Gaussian Wavelet Function Employing Dynamic Translinear Circuits for Cardiac Signal Characterization

An analog QRS complex detection circuit, for pacemaker applications, based on the Wavelet Transform (WT) is presented here. The system detects the modulus maxima of the QRS complex. It consists of a wavelet transform fi lter, an absolute value circuit, a peak detector and a comparator. In order to achieve the low -power requirement in pacemakers, we propose a new method for implementing the WT in an analog way by means of the Dynamic Translinear (DTL) circuit technique. Simulations indicate a good performance of the Wavelet Transform and the QRS complex detection. The resulting circuit operates from a 2-V supply voltage, dissipates at most 55nW per scale and can be fully integrated.