74166
74166 8-Bit Parallel-In/Serial-Out Shift Register
Overview
The 74166 is a high-speed, 8-bit parallel-in/serial-out shift register integrated circuit. This versatile component is designed for applications requiring serial data transmission, data storage, or data manipulation. The device features synchronous parallel loading, serial data input, and clocked serial shifting operations, making it suitable for a wide range of digital systems.
Constructed using advanced silicon-gate technology, the 74166 offers improved performance characteristics compared to standard TTL implementations. The device operates with a typical propagation delay of 13ns, enabling high-speed data transfer applications. The 74166 is available in multiple package options, including plastic dual-in-line (PDIP) and small-outline (SOIC) packages, providing flexibility for various design requirements.
Key Features
- High-speed operation: 13ns typical propagation delay
- 8-bit parallel input with synchronous loading
- Serial data input for daisy-chaining applications
- Direct overriding clear input
- Clock inhibit capability for system timing control
- Compatible with most TTL and DTL logic families
- Wide operating voltage range: 4.5V to 5.5V
- Low power consumption: 45mW typical
- Operating temperature range: -55°C to +125°C (military grade)
- Available in multiple package options
Applications
The 74166 shift register finds application in numerous digital systems, including:
- Serial-to-parallel data conversion
- Data buffering and temporary storage
- Digital delay lines
- Sequence generators
- Keyboard encoding systems
- Communication systems
- Industrial control systems
- Test and measurement equipment
- Computer peripheral interfaces
Electrical Characteristics
Absolute Maximum Ratings
| Parameter | Value | Unit |
|---|---|---|
| Supply Voltage (Vcc) | 7 | V |
| Input Voltage | 5.5 | V |
| Operating Free Air Temperature Range | -55 to +125 | °C |
| Storage Temperature Range | -65 to +150 | °C |
Recommended Operating Conditions
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| Supply Voltage (Vcc) | 4.5 | 5.0 | 5.5 | V |
| High-Level Input Voltage | 2.0 | - | - | V |
| Low-Level Input Voltage | - | - | 0.8 | V |
| Clock Frequency | - | - | 35 | MHz |
| Operating Free Air Temperature | -55 | 25 | 125 | °C |
DC Electrical Characteristics
| Parameter | Test Conditions | Min | Typ | Max | Unit |
|---|---|---|---|---|---|
| High-Level Output Voltage | Vcc = Min, Ioh = -400µA | 2.4 | 3.4 | - | V |
| Low-Level Output Voltage | Vcc = Min, Iol = 16mA | - | 0.2 | 0.4 | V |
| Input Clamp Voltage | Vcc = Min, Ii = -12mA | - | -1.5 | - | V |
| High-Level Input Current | Vcc = Max, Vi = 2.7V | - | 20 | 40 | µA |
| Low-Level Input Current | Vcc = Max, Vi = 0.4V | - | -0.8 | -1.6 | mA |
Functional Description
The 74166 is a versatile 8-bit shift register that can operate in several modes. The device features parallel inputs (A-H) that are loaded into the register when the parallel load (PL) input is low. When PL is high, data is shifted on the rising edge of the clock pulse. The serial input (SER) allows for daisy-chaining multiple devices.
The clock inhibit (CLK INH) input, when high, prevents clock pulses from affecting the register. The clear (CLR) input, when low, asynchronously resets all flip-flops in the register. The device outputs the last bit of the register at the QH output, while the complementary output (QH') provides the inverted signal.
Package Information
Available Packages
- PDIP-16: Plastic Dual In-Line Package, 16 pins, 0.3" width
- SOIC-16: Small Outline Integrated Circuit, 16 pins, 150 mil body width
- CDIP-16: Ceramic Dual In-Line Package, 16 pins (military grade)
