Invention Grant
US08981653B2 Flash driver to limit a load current of a flash and method to limit a load current of a flash driver
有权
闪光驱动器限制闪光灯的负载电流和限制闪存驱动器的负载电流的方法
- Patent Title: Flash driver to limit a load current of a flash and method to limit a load current of a flash driver
- Patent Title (中): 闪光驱动器限制闪光灯的负载电流和限制闪存驱动器的负载电流的方法
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Application No.: US13840032Application Date: 2013-03-15
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Publication No.: US08981653B2Publication Date: 2015-03-17
- Inventor: Peter Trattler , Karl Georg Waser
- Applicant: ams AG
- Applicant Address: AT Unterpremstaetten
- Assignee: ams AG
- Current Assignee: ams AG
- Current Assignee Address: AT Unterpremstaetten
- Agency: McDermott Will & Emery LLP
- Priority: EP12164140 20120413
- Main IPC: H05B41/00
- IPC: H05B41/00 ; H05B41/30 ; H05B41/16 ; H05B41/36 ; G05F1/00 ; G03B7/26 ; G03B15/05 ; H05B33/08

Abstract:
A flash driver to limit a load current for a flash comprises a dc/dc converter (DCDC) having a first input (IN1) to receive an input voltage (Vin) and an output (OUT) to supply an output voltage (Vout). The dc/dc converter is designed to convert the input voltage (Vin) to the output voltage (Vout). Furthermore the flash driver has an adjustable current source (Iadj) connected between the output (OUT) and a load terminal (LT). A first control unit (CTRL—1) is connected to the first input (IN1) and coupled to the adjustable current source (Iadj), and is designed to compare the input voltage (Vin) to a threshold (Vth) and, if the comparison indicates the input voltage (Vin) being smaller than the threshold value (Vth), adjust the adjustable current source (Iadj) such that the input voltage (Vin) is equal or greater than the threshold value (Vth). A second control unit (CTRL—2) is coupled to the adjustable current source (Iadj) and the dc/dc converter (DCDC) and is designed to detect a voltage drop over the adjustable current source (Iadj) and to set the dc/dc converter (DCDC) to control the conversion of input voltage (Vin) to the output voltage (Vout) depending on the detected voltage drop.
Public/Granted literature
- US20130272688A1 FLASH DRIVER TO LIMIT A LOAD CURRENT OF A FLASH AND METHOD TO LIMIT A LOAD CURRENT OF A FLASH DRIVER Public/Granted day:2013-10-17
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