发明名称 |
Capacitively-coupled amplifier with improved low frequency response |
摘要 |
A capacitively-coupled amplifier circuit includes an amplifier for receiving an input signal via a coupling capacitance and for amplifying the input signal to produce an output signal. A resistor provides a bias voltage to the amplifier. The resistor is bootstrapped using positive feedback with a loop gain of slightly less than one. The bootstrapping causes an increase in the value of the resistor to lower the cut-in (pole) frequency of the amplifier. The bootstrapping or feedback circuit includes a roll-off (pole) at a frequency below the roll-off (pole) frequency of the amplifier. This prevents phase shift in the feedback loop from adversely effecting the high frequency response of the amplifier. The resulting amplifier circuit exhibits a wide passband and excellent low frequency response despite having a capacitively coupled input signal.
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申请公布号 |
US5392001(A) |
申请公布日期 |
1995.02.21 |
申请号 |
US19940202329 |
申请日期 |
1994.02.28 |
申请人 |
HEWLETT-PACKARD COMPANY |
发明人 |
UHLING, THOMAS F.;HEUMANN, JOHN M.;PEIFFER, RONALD J. |
分类号 |
G01R1/067;G01R1/30;H03F1/08;H03F1/48;(IPC1-7):H03F1/38 |
主分类号 |
G01R1/067 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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