Invention Grant
- Patent Title: DLL circuit and semiconductor device
- Patent Title (中): DLL电路和半导体器件
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Application No.: US14762532Application Date: 2014-01-28
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Publication No.: US09543967B2Publication Date: 2017-01-10
- Inventor: Hiroki Takahashi
- Applicant: PS4 Luxco S.a.r.l.
- Applicant Address: LU Luxembourg
- Assignee: LONGITUDE SEMICONDUCTOR S.A.R.L.
- Current Assignee: LONGITUDE SEMICONDUCTOR S.A.R.L.
- Current Assignee Address: LU Luxembourg
- Agency: Kunzler Law Group, PC
- Priority: JP2013-014453 20130129
- International Application: PCT/JP2014/051810 WO 20140128
- International Announcement: WO2014/119558 WO 20140807
- Main IPC: H03L7/08
- IPC: H03L7/08 ; G11C11/4076 ; G11C7/22 ; H03L7/081

Abstract:
In accordance with disclosed embodiments, a DLL circuit includes a variable frequency division circuit that uses a variable frequency division ratio to frequency-divide a first clock signal to generate first and second frequency-divided clock signals, a grain size change circuit that changes the count width in synchronization with the first frequency-divided clock signal, a counter circuit that updates the count value in accordance with the count width in synchronization with the second frequency-divided clock signal, and a variable delay circuit that delays the first clock signal on the basis of a delay amount that is in accordance with the count value, thereby generating a second clock signal. When the relationship in magnitude between the phase difference between the first and second clock signals and a predetermined value becomes inverse just after the updating of the count value, the grain size change circuit changes the count width, and the variable frequency division circuit sets the frequency division ratio of the second frequency-divided clock signal being greater than that of the first frequency-divided clock signal.
Public/Granted literature
- US20150372683A1 DLL CIRCUIT AND SEMICONDUCTOR DEVICE Public/Granted day:2015-12-24
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