发明名称 |
Dual-function double balanced mixer circuit |
摘要 |
A circuit for connecting multiple signal paths within a multi-mode communication device includes a double balanced mixer circuit selectively functioning as a modulation switch during an unbalanced state. As applied to a transmit section of a CDMA/FM cellular telephone, a dual-function double balanced mixer circuit connects a CDMA IF signal path with an FM audio signal path. The double balanced mixer circuit includes a double balanced mixer connected through oscillator input to an external LC (inductor-capacitor) tank connected to both a PLL (phase lock loop) and an FM audio signal. One signal input of the double balanced mixer receives a CDMA low IF signal, while the other double balanced mixer signal input is connected to a microprocessor-controlled switch for selectively unbalancing the balanced mixer while in the FM mode of operation.
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申请公布号 |
US5649288(A) |
申请公布日期 |
1997.07.15 |
申请号 |
US19950468019 |
申请日期 |
1995.06.06 |
申请人 |
OKI TELECOM |
发明人 |
DE LOE, JR., JOHN P.;WANG, HE FENG |
分类号 |
H03D7/14;H04B1/04;(IPC1-7):H04Q7/00;H04Q9/00 |
主分类号 |
H03D7/14 |
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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