1. General description

The HEF4520B is a dual 4-bit internally synchronous binary counter with two clock inputs (nCP0

and nCP1), buffered outputs from all four bit positions (nQ0 to nQ3) and an asynchronous master

reset input (nMR). The counter advances on either the LOW-to-HIGH transition of nCP0 if nCP1

is HIGH or the HIGH-to-LOW transition of nCP1 if nCP0 is LOW. Either nCP0 or nCP1 may be

used as the clock input to the counter and the other clock input may be used as a clock enable

input. A HIGH on nMR resets the counter (nQ0 to nQ3 = LOW) independent of nCP0 and nCP1.

Inputs include clamp diodes. This enables the use of current limiting resistors to interface inputs to

voltages in excess of VDD.

2. Features and benefits

• Tolerant of slow clock rise and fall times

• Fully static operation

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

• Wide supply voltage range from 3.0 V to 15.0 V

• CMOS low power dissipation

• High noise immunity

• Standardized symmetrical output characteristics

• Complies with JEDEC standard JESD 13-B

• ESD protection:

• HBM JESD22-A114F exceeds 2000 V

• MM JESD22-A115-B exceeds 200 V

• Specified from -40 °C to +85 °C

HEF4520BT属于集成电路（IC） > 计数器，除法器。安世半导体(中国)有限公司制造生产的HEF4520BT计数器，除法器计数器和除法器 IC 是数字逻辑器件，可对输入发生的逻辑转换进行计数，然后使用多个并行输出重新发送累加的计数，和/或生成单个输出信号转换，从而对应用某些整数数量输入信号转换进行响应。除了简单的事件计数，它们还可用于各种频率合成应用。