发明名称 |
ADPLL CIRCUIT, SEMICONDUCTOR DEVICE, AND PORTABLE INFORMATION DEVICE |
摘要 |
The present invention provides ABS precision improving means under ADPLL environment or environment close to the ADPLL environment and realizes shortening of process time of the ABS. In a digital frequency comparator in an ABS circuit, a DFF for storing an initial phase difference in a DPE signal output from a DPFD is prepared. Immediately after start of ABS operation, a DPE signal output from the DPFD is recorded as a signal expressing an initial phase difference in an internal circuit of the DPFD into the DFF. After that, the digital frequency comparator performs ABS by using a signal obtained by subtracting the initial phase error recorded in the DFF from an input DPE signal, thereby realizing high-speed and stabilized ABS operation.
|
申请公布号 |
US2013009681(A1) |
申请公布日期 |
2013.01.10 |
申请号 |
US201213616449 |
申请日期 |
2012.09.14 |
申请人 |
RENESAS ELECTRONICS CORPORATION;ENDO RYO;SHIMBO JIRO;KITAMURA TOMOMITSU |
发明人 |
ENDO RYO;SHIMBO JIRO;KITAMURA TOMOMITSU |
分类号 |
H03L7/08 |
主分类号 |
H03L7/08 |
代理机构 |
|
代理人 |
|
主权项 |
|
地址 |
|