Overview
The SN74HC148DWR is an 8-input priority encoder produced by Texas Instruments. This device is part of the HC148 series, which features priority decoding of the inputs to ensure that only the highest-order data line is encoded. The SN74HC148DWR is designed to operate over a wide voltage range and is suitable for various digital encoding applications. It includes input enable (EI) and output enable (EO) signals, allowing for the cascading of multiple stages without the need for additional external circuitry.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| VCC Supply Voltage | 2 | 5 | 6 | V |
| VIH High-Level Input Voltage (VCC = 2V) | 1.5 | V | ||
| VIH High-Level Input Voltage (VCC = 4.5V) | 3.15 | V | ||
| VIH High-Level Input Voltage (VCC = 6V) | 4.2 | V | ||
| VIL Low-Level Input Voltage (VCC = 2V) | 0.5 | V | ||
| VIL Low-Level Input Voltage (VCC = 4.5V) | 1.35 | V | ||
| VIL Low-Level Input Voltage (VCC = 6V) | 1.8 | V | ||
| Propagation Delay (tpd) A0, A1, A2 (VCC = 2V) | 69 | 180 | 270 | ns |
| Propagation Delay (tpd) A0, A1, A2 (VCC = 4.5V) | 23 | 36 | 54 | ns |
| Propagation Delay (tpd) A0, A1, A2 (VCC = 6V) | 21 | 31 | 46 | ns |
| ICC Supply Current (VCC = 6V) | 80 | μA | ||
| IOH Output Current (VCC = 5V, IOH = -4mA) | 3.98 | mA | ||
| IOL Output Current (VCC = 5V, IOL = 4mA) | 0.17 | V | ||
| TJ Junction Temperature | 150 | °C |
Key Features
- Wide operating voltage range of 2V to 6V
- Outputs can drive up to 10 LSTTL loads
- Low power consumption, 80-μA max
- Typical propagation delay (tpd) = 16ns
- ±4-mA output drive at 5V
- Low input current of 1μA max
- Encode eight data lines to 3-line binary (Octal)
- Input enable (EI) and output enable (EO) signals for cascading multiple stages
Applications
- N-Bit encoding
- Code converters and generators
- Priority decoding in digital systems
- Cascaded encoding applications
Q & A
- What is the primary function of the SN74HC148DWR? The primary function is to encode eight data lines into a 3-line binary (Octal) output with priority decoding.
- What is the operating voltage range of the SN74HC148DWR? The operating voltage range is from 2V to 6V.
- How many LSTTL loads can the outputs drive? The outputs can drive up to 10 LSTTL loads.
- What is the typical propagation delay of the SN74HC148DWR? The typical propagation delay (tpd) is 16ns.
- What is the maximum supply current of the SN74HC148DWR? The maximum supply current (ICC) is 80 μA.
- Can the SN74HC148DWR be cascaded? Yes, it can be cascaded using the input enable (EI) and output enable (EO) signals.
- What is the maximum junction temperature for the SN74HC148DWR? The maximum junction temperature (TJ) is 150°C.
- What are some common applications of the SN74HC148DWR? Common applications include N-Bit encoding, code converters, and generators.
- What is the package type for the SN74HC148DWR? The package type is SOIC (D) with 16 pins.
- What is the operating temperature range for the SN74HC148DWR? The operating temperature range is from -40°C to 85°C.
