| 摘要 |
A system for playing back a wide dynamic amplitude range analog signal that is digitized in floating point word form. The word being represented in digital signal form by the general algebraic form Q=+/-AB-N where Q represents the amplitude of the analog signal, A represents the mantissa, B indicates the radix of the number system used, N represents the number of fixed gain amplifier steps, and is the exponent of B, each word is represented by a first plurality of binary bits representing N. The playback system includes a first converter receiving a reference voltage which converts the bits representing A to an interim analog signal. A second converter converts the bits representing N to a plurality of control signals. A resistor network is connected to ground and has N number of inputs and an output. The resistor network provides a signal which is a reduction of the interim analog signal applied to one of the inputs, the reduction being determined by which input the interim analog signal was applied to. Each switch of a plurality of switches is connected to the first and second converters, to ground and to a corresponding input of the resistor network. Each switch is responsive to the corresponding control signal either to apply the interim analog signal to the corresponding input of the resistor network when the control signal is at another logic level. An amplifier connected to the resistor network amplifies the output signal from the resistor network to provide an amplified signal corresponding to the wide dynamic amplitude range analog signal.
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