发明名称 |
Frequency generator and communication system using the same |
摘要 |
A frequency generator which can perform stable frequency oscillation unaffected by temperature variation. A frequency generator having a differential amplifier ( 1 ) having an LC resonance circuit ( 10 ) as a load and buffer circuits ( 21, 22 ) feeding back an output of the differential amplifier to its input, wherein a temperature coefficient converter ( 5 ) converting an output voltage of a reference voltage generator ( 4 ) and its temperature dependence to a voltage having a predetermined voltage and temperature coefficient and outputting it is provided to control bias currents IEF of emitter follower circuits to be in proportion to temperature variation. There are a characteristic in which delay time of the emitter follower circuits constructing the buffer circuits is in inverse proportion to a transconductance of transistors and a characteristic in which the transconductance is in inverse proportion to temperature and is in proportion to the bias currents IEF. An oscillation frequency stable to temperature variation can be obtained. |
申请公布号 |
US7177612(B2) |
申请公布日期 |
2007.02.13 |
申请号 |
US20040901966 |
申请日期 |
2004.07.30 |
申请人 |
RENESAS TECHNOLOGY CORP. |
发明人 |
NAKAMURA TAKAHIRO;OHHATA KENICHI;MASUDA TORU |
分类号 |
H03B5/04;H04B7/00;H03B5/12;H03F1/30;H03F3/343;H03F3/345;H03F3/45;H03F3/50;H04B1/16;H04B1/18;H04B1/26 |
主分类号 |
H03B5/04 |
代理机构 |
|
代理人 |
|
主权项 |
|
地址 |
|