Invention Grant
- Patent Title: Tri-state pulse density modulator
- Patent Title (中): 三态脉冲密度调制器
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Application No.: US11107686Application Date: 2005-04-15
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Publication No.: US07283012B2Publication Date: 2007-10-16
- Inventor: Meoung-Jin Lim
- Applicant: Meoung-Jin Lim
- Applicant Address: US CA San Diego
- Assignee: Via Telecom., Ltd.
- Current Assignee: Via Telecom., Ltd.
- Current Assignee Address: US CA San Diego
- Agency: Preston Gates & Ellis LLP.
- Main IPC: H03K7/06
- IPC: H03K7/06

Abstract:
A tri-state pulse density modulator includes a first switch device coupled to a high voltage, and a second switch device coupled to a low voltage. An adder receives a pulse density modulation (PDM) input signal and a latched input signal to generate an output sum signal and a carry signal. A latch module coupled with the adder latches the output sum signal with a clock signal to generate the latched input signal. A control circuit module responsive to the carry signal for selectively turns off the first and second switch devices to generate the PDM output signal at a tri-state voltage between the first and second voltages, or turns on the first or second switch device to generate the PDM output signal at the first or second voltage, respectively. Thus, the PDM output signal only switches between the tri-state voltage and either the first voltage or the second voltage.
Public/Granted literature
- US20060233234A1 Tri-state pulse density modulator Public/Granted day:2006-10-19
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