Overview
The CD74HC390EG4, produced by Texas Instruments, is a high-speed CMOS logic dual decade ripple counter. This device includes two independent 4-bit decade counters, each consisting of a divide-by-2 and a divide-by-5 counter. The counters are falling-edge clocked with asynchronous clear inputs, allowing for flexible configuration and use in various digital circuits.
The CD74HC390EG4 is part of the HC (High-Speed CMOS) family, known for its low power consumption and high noise immunity. It operates over a wide temperature range of -55°C to 125°C, making it suitable for a variety of applications.
Key Specifications
| Parameter | Unit | Min | Typ | Max |
|---|---|---|---|---|
| VCC Supply Voltage Range | V | 2 | - | 6 |
| Input Voltage Range | V | 0 | - | VCC |
| Output Source/Sink Current per Output Pin | mA | -25 | - | 25 |
| Junction Temperature | °C | - | - | 150 |
| Storage Temperature Range | °C | -65 | - | 150 |
| Maximum Clock Frequency at VCC = 5V | MHz | - | 35 | - |
| Propagation Delay (nCLK to nQx) at VCC = 5V | ns | - | 30-45 | - |
| Output Transition Times at VCC = 5V | ns | - | 75 | - |
Key Features
- Two independent 4-bit decade ripple counters, each consisting of a divide-by-2 and a divide-by-5 counter.
- Flexible configuration: can be configured to divide-by-2, 4, 5, 10, 20, 25, 50, 100.
- Asynchronous clear inputs to clear each decade counter individually.
- Wide operating temperature range: -55°C to 125°C.
- High noise immunity: NIL = 30%, NIH = 30% of VCC at VCC = 5V.
- Low power consumption compared to LSTTL logic ICs.
- Direct LSTTL input logic compatibility for HCT types.
- CMOS input compatibility with low input current (II ≤ 1 μA).
Applications
- Digital counters and timers in various electronic systems.
- Frequency dividers and clock generators.
- Automotive and industrial control systems requiring robust and reliable counting functions.
- Consumer electronics such as calculators, digital clocks, and other timing devices.
- Medical devices that require precise timing and counting functions.
Q & A
- What is the CD74HC390EG4?
The CD74HC390EG4 is a high-speed CMOS logic dual decade ripple counter produced by Texas Instruments.
- What are the key components of the CD74HC390EG4?
The device includes two independent 4-bit decade counters, each consisting of a divide-by-2 and a divide-by-5 counter.
- What is the operating voltage range of the CD74HC390EG4?
The operating voltage range is from 2V to 6V for HC types.
- What is the maximum clock frequency of the CD74HC390EG4?
The maximum clock frequency at VCC = 5V is approximately 35 MHz.
- Does the CD74HC390EG4 have asynchronous clear inputs?
- What is the temperature range of the CD74HC390EG4?
The device operates over a wide temperature range of -55°C to 125°C.
- What are some common applications of the CD74HC390EG4?
Common applications include digital counters and timers, frequency dividers, automotive and industrial control systems, consumer electronics, and medical devices.
- How does the CD74HC390EG4 handle noise immunity?
The device has high noise immunity with NIL = 30%, NIH = 30% of VCC at VCC = 5V.
- Is the CD74HC390EG4 compatible with LSTTL logic?
- What is the recommended power supply configuration for the CD74HC390EG4?
A good bypass capacitor (e.g., 0.1-μF) should be used close to the power terminal to prevent power disturbances.
