| 摘要 |
<p>A charge balanced feedback type transmitter (10) generates charge packets representative of a sensed parameter. Improved performance is achieved by the addition of resistance (R1), (R2) connected between a charge packet generating reactance (C1), (C2), (CL1), (CL2) and an integrator (30) to reduce the effects of noise caused by switching transients and by ground noise which is coupled to the charge packet generating circuitry (12) by stray capacitance. The charge packets are integrated by the integrator (30), and the integrator output is supplied from a selective basis to the input of a comparator (32). The output of the comparator (32) is used to control the application of balance. The input of the comparator (32) is selectively connected to the output of the integrator (30), to a first supply voltage, or to a second supply voltage to ensure a stable output of the comparator (32) at a critical time when charge is being supplied to the integrator (30).</p> |
