The **74HC393D-Q100J** is a high-speed CMOS device commonly used in digital electronics for counting and frequency division applications. The "Q100" suffix indicates that it is an **automotive-grade** component, having passed the AEC-Q100 stress test qualifications. --- ### 1. General Specifications The device contains two independent 4-bit binary ripple counters, each with its own clock input ($CP$) and master reset ($MR$). | Feature | Specification | | :--- | :--- | | **Logic Family** | 74HC (High-speed CMOS) | | **Package** | SO14 (Small Outline, 14 pins) | | **Supply Voltage ($V_{CC}$)** | 2.0V to 6.0V | | **Counter Type** | Dual 4-bit Binary Ripple Counter | | **Max Frequency** | ~79 MHz (at 6.0V) | | **Operating Temp** | -40°C to +125°C | | **Qualification** | AEC-Q100 (Automotive Grade) | --- ### 2. Pin Configuration The 14-pin layout is divided into two identical sections (1 and 2). | Pin No. | Symbol | Description | | :--- | :--- | :--- | | 1 | 1CP | Clock Input, Counter 1 (Negative-edge triggered) | | 2 | 1MR | Master Reset, Counter 1 (Active HIGH) | | 3 to 6 | 1Q0 - 1Q3 | Parallel Outputs, Counter 1 | | 7 | GND | Ground (0V) | | 8 to 11 | 2Q3 - 2Q0 | Parallel Outputs, Counter 2 | | 12 | 2MR | Master Reset, Counter 2 (Active HIGH) | | 13 | 2CP | Clock Input, Counter 2 (Negative-edge triggered) | | 14 | $V_{CC}$ | Supply Voltage | --- ### 3. Functional Logic Each 4-bit counter is composed of four T-type flip-flops. - **Counting:** The counter increments on the **High-to-Low transition** (falling edge) of the clock input ($CP$). - **Resetting:** A HIGH level on the Master Reset ($MR$) pin asynchronously clears all flip-flops and sets the outputs ($Q0$ to $Q3$) to LOW, regardless of the clock state. - **Cascading:** By connecting the $Q3$ output of the first counter to the $CP$ input of the second counter, you can create an **8-bit binary counter** (counting up to 255). --- ### 4. Typical Applications * **Frequency Division:** Dividing a high-frequency clock down to a lower frequency for timing circuits. * **Time Delay Generation:** Creating specific pulses after a set number of clock cycles. * **Event Counting:** Keeping track of sensor pulses in automotive or industrial environments. * **Digital Clocks:** Serving as the base for seconds, minutes, or hours counters. ---