SN74HC191DR by TI Design and production,in Shenzhen Yirenxin Technology Co., Ltd. Spot sales,And can pass Shenzhen Yirenxin Technology Co., Ltd. Purchasing。SN74HC191DR Price reference $ 0。SN74HC191DR - 。You can download Chinese information、Pin map、DatasheetData sheet function specification,In the information SN74HC191DR Detailed pin diagram and function application circuit diagram voltage and usage method and tutorial