1. General description

The HEF4794B is an 8-stage serial shift register. It has a storage latch associated with each

stage for strobing data from the serial input (D) to the parallel LED driver outputs (QP0 to QP7).

Data is shifted on the positive-going clock (CP) transitions. The data in each shift register stage

is transferred to the storage register when the strobe input (STR) is HIGH. Data in the storage

register appears at the outputs whenever the output enable input (OE) signal is HIGH.

Two serial outputs (QS1 and QS2) are available for cascading a number of HEF4794B devices.

Serial data is available at QS1 on positive-going clock edges to allow high-speed operation in

cascaded systems with a fast clock rise time. The same serial data is available at QS2 on the next

negative going clock edge. This is used for cascading HEF4794B devices when the clock has a

slow rise time.

It operates over a recommended VDD power supply range of 3 V to 15 V referenced to VSS (usually

ground). Unused inputs must be connected to VDD, VSS, or another input.

2. Features and benefits

• Wide supply voltage range from 3.0 V to 15.0 V

• CMOS low power dissipation

• High noise immunity

• Fully static operation

• 5 V, 10 V, and 15 V parametric ratings

• Standardized symmetrical output characteristics

• Complies with JEDEC standard JESD 13-B

• ESD protection:

• HBM JESD22-A114F exceeds 2000 V

• MM JESD22-A115-A exceeds 200 V

• Specified from -40 °C to +85 °C and -40 °C to +125 °C

HEF4794B属于集成电路（IC） > LED 驱动器。安世半导体(中国)有限公司制造生产的HEF4794BLED 驱动器器件属于 LED 驱动器电源管理集成电路 (PMIC) 系列，可通过标称固定电压的电源为负载（通常为发光二极管）提供电流，并且电流可控。它与用于电压调节的类似产品的主要区别在于，这类器件提供较低的反馈电压（以提高系统能效），而且通常可对器件工作点进行外部控制，可在照明应用中用于实现调光功能。