Invention Grant
- Patent Title: Digital to analog converter with reduced output noise
- Patent Title (中): 具有降低输出噪声的数模转换器
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Application No.: US11038242Application Date: 2005-01-21
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Publication No.: US07106234B2Publication Date: 2006-09-12
- Inventor: John Oliver O'Connell , Colin Lyden
- Applicant: John Oliver O'Connell , Colin Lyden
- Applicant Address: IE Cork US MA Norwood
- Assignee: University College Cork - National University of Ireland,Analog Devices, Inc.
- Current Assignee: University College Cork - National University of Ireland,Analog Devices, Inc.
- Current Assignee Address: IE Cork US MA Norwood
- Agency: Jacobson Holman PLLC
- Main IPC: H03M1/66
- IPC: H03M1/66

Abstract:
A DAC (1) has a switched element capacitor (7, Cr) to which charge is delivered via switches (6, S1/S2) depending on required analog voltage level (Vref1, Vref2). An output switch (S3) is closed and a ground switch (S4) is opened to deliver charge to the output according to received bi-level digital inputs (+1, −1). The control block (2) has a memory and determines an inactive output level if there is an input digital transition from +1 to −1 or from −1 to +1. For the inactive level S3 is kept open and S4 is kept closed. Thus, for every clock cycle with one of these transitions there is no charge transfer and hence no thermal noise. Overall noise is therefore considerably reduced.
Public/Granted literature
- US20050185475A1 Digital to analog converters Public/Granted day:2005-08-25
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