In the voltage reference circuit shown in the figure, the op-amp is ideal and the transistors Q₁, Q₂,….., Q₃₂ are identical in all respects and have infinitely large values of common – emitter current gain $$\beta $$. The collector current (I_C) of the transistors is related to their base emitter voltage (V_BE) by the relation I_C = I_S exp (V_BE/V_T); where I_s is the saturation current. Assume that the voltage V_P shown in the figure is 0.7 V and the thermal voltage V_T=26mV

The output voltage V_out (in volts) is _____.

Consider a binary memoryless channel characterized by the transition probability diagram shown in the figure. The channel is

Consider the random process
x(t) = U + Vt.
Where U is a zero mean Gaussian random variable and V is a random variable uniformly distributed between 0 and 2. Assume that U and V are statistically independent. The mean value of the random process at t = 2 is _________________

A sinusoidal message signal is converted to a PCM signal using a uniform quantizer. The required signal to quantization noise ratio (SQNR) at the output of the quantizer is 40dB. The minimum number of bits per sample needed to achieve the desired SQNR is ________ .