发明名称 |
Temperature-coefficient controlled radio frequency signal detecting circuitry |
摘要 |
A TC controlled RF signal detecting circuitry (211) used in the output power control circuit of a TDMA RF signal power amplifier includes positive coefficient current source (303) producing current I+ having a positive TC, negative coefficient current source (305) producing current I- having a negative TC, and current mirror (301) for summing currents I+ and I- to produce substantially identical compensated mirror currents Im1 and Im2. Anti-clamping current mirror (309) mirrors current Im2 to produce compensated currents Ia1 and Ia2, which are applied to and bias a Schottky diode coupled in series to a resistor network in each leg of diode detector (311). Each leg of diode detector (311) has a positive TC, which is substantially offset by the negative TC of compensated currents Ia1 and Ia2. Schottky diode (431) in one leg of diode detector (311) half-wave rectifies RF feedback signal (212) to produce temperature and voltage compensated power level signal (229), which has a DC level proportional to the output power level of RF output signal (214). By using TC controlled RF signal detecting circuitry (211), power level signal (229) has a DC level which is stable to within 5 mV over temperature ranging from -55 DEG C. to +125 DEG C. and over power supply voltage ranging from 2.7 V to 4.75 V.
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申请公布号 |
US5448770(A) |
申请公布日期 |
1995.09.05 |
申请号 |
US19930042956 |
申请日期 |
1993.04.05 |
申请人 |
MOTOROLA, INC. |
发明人 |
HIETALA, ALEXANDER W.;STOCKSTAD, TROY L.;VYNE, ROBERT L. |
分类号 |
H04B1/18;H03D1/02;H03D1/10;H03D1/18;H04B1/40;(IPC1-7):H04B1/04;H03F3/10;H03G3/12 |
主分类号 |
H04B1/18 |
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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