发明名称 |
Read only memory control circuit for use in a phase lock loop |
摘要 |
A control circuit comprising a read-only memory has its storage area divided into two areas each containing the same number of addressasble words. By arranging that input of a single address signal causes a change from addressing a particular wood in one area to addressing a corresponding word in the other area, and by programming a fixed difference in value between corresponding words in the two areas causes a step function in the output. Using a digital to analogue converter on the output of the circuit permits a step change in a voltage output to be provided to (e.g.) a voltage controlled oscillator. A control circuit using a read-only memory as a voltage comparator is also disclosed.
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申请公布号 |
US4692713(A) |
申请公布日期 |
1987.09.08 |
申请号 |
US19850807629 |
申请日期 |
1985.12.11 |
申请人 |
PLESSEY OVERSEAS LIMITED |
发明人 |
CORDWELL, BRIAN;HAYES, PAUL M. |
分类号 |
G06F1/03;G06F7/02;G06J1/00;H03L7/093;H03L7/10;(IPC1-7):H03L7/08;H03M1/70 |
主分类号 |
G06F1/03 |
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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