Overview
The MC74VHC138DR2G is an advanced high-speed CMOS 3-to-8 decoder fabricated with silicon gate CMOS technology. It is designed to achieve high-speed operation similar to equivalent Bipolar Schottky TTL while maintaining the low power dissipation characteristic of CMOS devices. This decoder is part of the 74VHC logic family and is suitable for a wide range of applications requiring fast and efficient decoding functions.
When enabled, the device uses three binary select inputs (A0 - A2) to determine which one of the eight outputs (Y0 - Y7) will go low. The decoding function can be inhibited by holding the enable input E3 low or either E2bar or E1bar high, causing all outputs to go high. This feature facilitates cascade connections and use as an address decoder in memory systems.
Key Specifications
| Parameter | Description | Value |
|---|---|---|
| Logic Family | 74VHC | - |
| Logic Type | Line Decoder | - |
| No. of Outputs | 8 | - |
| IC Case / Package | SOIC-16 | - |
| No. of Pins | 16 | - |
| Supply Voltage Min | 2V | - |
| Supply Voltage Max | 5.5V | - |
| Operating Temperature Min | -55°C | - |
| Operating Temperature Max | 125°C | - |
| Propagation Delay (Typ) | 5.7ns at VCC = 5V | - |
| Power Dissipation (Max) | 4μA at TA = 25°C | - |
| Noise Immunity | 28% VCC | - |
| ESD Performance | HBM > 2000V; Machine Model > 200V | - |
Key Features
- High Speed Operation: Achieves propagation delays similar to Bipolar Schottky TTL.
- Low Power Dissipation: Maximum current consumption of 4μA at 25°C.
- High Noise Immunity: Input noise immunity of 28% VCC.
- Power Down Protection: Provided on inputs to protect against power-down conditions.
- Balanced Propagation Delays: Ensures consistent timing across all outputs.
- Wide Operating Voltage Range: Operates from 2V to 5.5V.
- Low Noise: Output low voltage (VOLP) of 0.8V maximum.
- Pin and Function Compatibility: Compatible with other standard logic families.
- Latchup Performance: Exceeds 300mA.
- ESD Protection: Human Body Model (HBM) > 2000V and Machine Model > 200V.
- Pb-Free and RoHS Compliant: Available in Pb-free packages.
Applications
- Memory Systems: Can be used as an address decoder for memory systems.
- Cascade Connections: Facilitates easy cascade connections for complex decoding tasks.
- Interface Between Different Voltage Systems: Allows interface between 5V and 3V systems.
- High-Speed Digital Circuits: Suitable for high-speed digital circuits requiring fast decoding functions.
- General Logic Circuits: Can be used in various general logic circuits where decoding is necessary.
Q & A
- What is the primary function of the MC74VHC138DR2G?
The primary function is to act as a 3-to-8 line decoder, determining which one of the eight outputs will go low based on the three binary select inputs.
- What is the operating voltage range of the MC74VHC138DR2G?
The device operates from 2V to 5.5V.
- What is the typical propagation delay of the MC74VHC138DR2G?
The typical propagation delay is 5.7ns at VCC = 5V.
- How many outputs does the MC74VHC138DR2G have?
The device has eight outputs (Y0 - Y7).
- What is the maximum current consumption of the MC74VHC138DR2G at 25°C?
The maximum current consumption is 4μA at 25°C.
- Is the MC74VHC138DR2G Pb-free and RoHS compliant?
Yes, the device is available in Pb-free packages and is RoHS compliant.
- What is the noise immunity of the MC74VHC138DR2G?
The noise immunity is 28% VCC.
- Can the MC74VHC138DR2G be used in memory systems?
Yes, it can be used as an address decoder for memory systems.
- What is the ESD performance of the MC74VHC138DR2G?
The ESD performance is HBM > 2000V and Machine Model > 200V.
- What package types are available for the MC74VHC138DR2G?
The device is available in SOIC-16 and TSSOP-16 packages.
