SN74F27 - Triple 3-Input NOR Gate | Texas Instruments
MPN: SN74F27 β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $0.45 | $0.45 |
| 10 | $0.38 | $3.80 |
| 100 | $0.29 | $29.00 |
| 500 | $0.24 | $120.00 |
| 1,000 | $0.19 | $190.00 |
Drop-in alternatives for SN74F27 β same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
SN74LS27
β Drop-Inπ Reference alternative (not in catalog)
SN74HC27
β Drop-Inπ Reference alternative (not in catalog)
SN74HCT27
β Drop-Inπ Reference alternative (not in catalog)
74F27D
β Drop-Inπ Reference alternative (not in catalog)
74F27PC
β Drop-Inπ Reference alternative (not in catalog)
SN74F27 Maximum Ratings & Electrical Characteristics
| Logic Family | 74F |
| Number of Channels | 3 |
| Number of Inputs per Gate | 3 |
| Supply Voltage Range | 4.5 V to 5.5 V |
| Operating Temperature Range | 0Β°C to 70Β°C |
| Propagation Delay Time | 5.5 ns (typical) |
| Output Current | 20 mA |
| Logic Function | NOR |
| Package Type | SOIC-14, PDIP-14, CDIP-14 |
| Mounting Type | Surface Mount or Through Hole |
| RoHS Status | Compliant |
| REACH Status | Compliant |
| AEC-Q100 Qualified | No |
| Lead-Free | Yes |
| Halogen-Free | Yes |
SN74F27 Pin Configuration
| Pin 1 | 1A β Input A of gate 1 |
| Pin 2 | 1B β Input B of gate 1 |
| Pin 3 | 1C β Input C of gate 1 |
| Pin 4 | 1Y β Output of gate 1 |
| Pin 5 | 2A β Input A of gate 2 |
| Pin 6 | 2B β Input B of gate 2 |
| Pin 7 | GND β Ground |
| Pin 8 | 2C β Input C of gate 2 |
| Pin 9 | 2Y β Output of gate 2 |
| Pin 10 | 3A β Input A of gate 3 |
| Pin 11 | 3B β Input B of gate 3 |
| Pin 12 | 3C β Input C of gate 3 |
| Pin 13 | 3Y β Output of gate 3 |
| Pin 14 | VCC β Positive supply voltage |
Safe Operating Area (SOA) & Thermal Characteristics
No official SOA curve available for this digital IC. Always operate within absolute maximum ratings specified in the datasheet. Ensure adequate cooling and derate as needed.
Typical Applications
SN74F27 is suitable for 6 applications: Address Decoding, Logic Function Generation, Data Path Logic, Test and Measurement Equipment, Industrial Control Systems, Consumer Electronics.
Address Decoding
The SN74F27 is used in address decoding circuits to select memory or peripheral devices based on address lines. Its high speed (5.5 ns propagation delay) ensures minimal decoding delay, which is critical for high-speed microprocessor systems. The triple 3-input NOR gates can be combined to implement complex decoding logic. For example, in a memory system, the SN74F27 can decode a 3-bit address to generate chip select signals. The device's 20 mA output drive can directly enable memory chips or buffers. When designing, ensure that the address lines are stable before the decode output is used to avoid glitches.
Recommended
Logic Function Generation
The SN74F27 can be used to generate arbitrary logic functions in combinational circuits. Its three independent 3-input NOR gates allow implementation of Boolean expressions such as Y = (A+B+C)'. The high-speed bipolar technology makes it suitable for arithmetic logic units (ALUs) and control logic where propagation delay affects system performance. For example, in a control unit, the SN74F27 can generate control signals based on opcode bits. The device's TTL-compatible outputs interface directly with other 74-series logic. When implementing logic functions, use Karnaugh maps to minimize the number of gates required.
Recommended
Data Path Logic
In data path circuits, the SN74F27 is used for operations such as zero detection, parity generation, and bus control. Its fast propagation delay (5.5 ns) ensures that data path operations do not become the bottleneck in high-speed processors. The device can be used to implement NOR-based logic functions that are common in ALUs. For example, a zero detector can be built using NOR gates to check if all bits of a data bus are LOW. The SN74F27's 20 mA output drive can drive bus transceivers or LEDs. When used in data paths, ensure proper signal integrity by minimizing trace lengths and using proper termination.
Recommended
Test and Measurement Equipment
The SN74F27 is used in test and measurement equipment for signal conditioning and logic analysis. Its high speed allows it to process high-frequency signals without introducing significant delay. The device can be used to build logic probes, pulse generators, and signal routing circuits. For example, in a logic analyzer, the SN74F27 can be used to detect specific logic patterns. The device's TTL compatibility ensures easy integration with other test equipment. When designing test equipment, consider the input impedance and loading effects on the signal under test.
Recommended
Industrial Control Systems
In industrial control systems, the SN74F27 is used for logic control functions such as interlocking, safety circuits, and sequence control. Its wide operating temperature range (0Β°C to 70Β°C) and robust bipolar design make it suitable for industrial environments. The device can be used to implement safety interlocks where multiple conditions must be met before a machine can operate. For example, a NOR gate can be used to ensure that a machine only operates when all safety switches are closed. The SN74F27's 20 mA output can drive relays or indicator LEDs. When used in industrial systems, ensure proper protection against electrical noise and transients.
Recommended
Consumer Electronics
The SN74F27 is used in consumer electronics for logic functions in remote controls, game consoles, and home appliances. Its low cost and availability in surface-mount packages make it ideal for high-volume production. The device can be used for button debouncing, mode selection, and status indication. For example, in a remote control, the SN74F27 can decode button presses and generate control signals. The device's TTL compatibility ensures easy interfacing with microcontrollers. When designing consumer electronics, consider power consumption and ESD protection.
Recommended
Recommended Products Summary
Engineering reference data for SN74F27 β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | SN74LS27 | SN74HC27 | SN74HCT27 | 74F27D | 74F27PC |
|---|---|---|---|---|---|---|
| Package | SOIC-14, PDIP-14 | SOIC-14, PDIP-14 | SOIC-14, PDIP-14 | SOIC-14, PDIP-14 | SOIC-14 | PDIP-14 |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | NXP Semiconductors | onsemi |
| Logic Family | 74F | 74LS | 74HC | 74HCT | 74F | 74F |
| Supply Voltage Range | 4.5V to 5.5V | 4.75V to 5.25V | 2V to 6V | 4.5V to 5.5V | 4.5V to 5.5V | 4.5V to 5.5V |
| Propagation Delay (typical) | 5.5 ns | 15 ns | 12 ns | 12 ns | 5.5 ns | 5.5 ns |
| Output Current | 20 mA | 8 mA | 4 mA | 4 mA | 20 mA | 20 mA |
| Technology | Bipolar | Bipolar | CMOS | CMOS | Bipolar | Bipolar |
| Operating Temperature Range | 0Β°C to 70Β°C | 0Β°C to 70Β°C | -40Β°C to 85Β°C | -40Β°C to 85Β°C | 0Β°C to 70Β°C | 0Β°C to 70Β°C |
Key Differentiators
- High-speed bipolar logic with 5.5 ns propagation delay (vs SN74LS27)
- Higher output drive capability (20 mA) (vs SN74HC27)
- Same logic family as other 74F devices (vs 74F27D (NXP))
Design Notes
The SN74F27 is a bipolar device and consumes more power than CMOS alternatives. At 5V, the typical ICC is around 10 mA, which can be significant in battery-powered applications. Ensure the power supply can provide adequate current. Use a 0.1-Β΅F decoupling capacitor close to the VCC pin to reduce noise.
For high-speed operation, keep traces short and minimize capacitive loading on the outputs. Use a ground plane to reduce noise and ensure signal integrity. Place the decoupling capacitor as close as possible to the VCC and GND pins. Avoid routing high-speed signals near the inputs to prevent crosstalk.
Unused inputs must be tied to a defined logic level, either VCC or GND, to prevent floating inputs that can cause excessive power consumption and unpredictable behavior. Do not exceed the maximum supply voltage of 5.5V. Ensure that the output current does not exceed 20 mA to avoid damaging the device.
Compliance Information
RoHS and REACH compliant per TI product page. Not AEC-Q100 qualified.
