Overview
The Texas Instruments SN74LS688NSR is an 8-bit magnitude/identity comparator, part of the 74LS series. This device is designed to compare two 8-bit binary or BCD words and provide outputs indicating whether the two words are equal (P = Q) or if one word is greater than the other (P > Q or P < Q). It is packaged in a 20-pin Small Outline (SO) package and is RoHS compliant, making it suitable for a wide range of digital logic applications.
Key Specifications
| Parameter | Description |
|---|---|
| Manufacturer | Texas Instruments |
| Part Number | SN74LS688NSR |
| Package | 20-SOIC (0.209, 5.30mm Width) |
| Number of Pins | 20 |
| Operating Temperature | 0°C to 70°C |
| Supply Voltage | 4.85V to 5.25V |
| Propagation Delay | 23 ns @ 5V, 45pF |
| Output Type | Active Low |
| Output Current | 400μA (High), 24mA (Low) |
| Max Supply Current | 65mA |
| Moisture Sensitivity Level (MSL) | 1 (Unlimited) |
| RoHS Status | ROHS3 Compliant, Lead Free |
Key Features
- Compares two 8-bit binary or BCD words and provides P = Q, P > Q, and P < Q outputs.
- Includes pull-up resistors on Q inputs.
- Totem-pole outputs.
- Surface mount packaging with a 20-pin SOIC package.
- Operating supply voltage of 5V.
- Low propagation delay of 23 ns @ 5V, 45pF.
- Active low output.
- Part of the 74LS series, known for its excellent price-performance ratio.
Applications
- Servo motor controls.
- Communications digital frequency synthesizers (VHF, UHF, FM, AM, etc.).
- Process control.
- Fixed or programmable frequency division.
- 'Time out' timer for consumer and industrial controls.
Q & A
- What is the primary function of the SN74LS688NSR? The primary function is to compare two 8-bit binary or BCD words and provide outputs indicating whether the two words are equal or if one word is greater than the other.
- What is the package type of the SN74LS688NSR? It is packaged in a 20-pin Small Outline (SO) package.
- What is the operating temperature range of the SN74LS688NSR? The operating temperature range is 0°C to 70°C.
- What is the supply voltage range for the SN74LS688NSR? The supply voltage range is 4.85V to 5.25V.
- What is the propagation delay of the SN74LS688NSR? The propagation delay is 23 ns @ 5V, 45pF.
- Is the SN74LS688NSR RoHS compliant? Yes, it is RoHS compliant and lead-free.
- What are some common applications of the SN74LS688NSR? Common applications include servo motor controls, communications digital frequency synthesizers, process control, and 'time out' timers for consumer and industrial controls.
- What type of outputs does the SN74LS688NSR have? The outputs are totem-pole and active low.
- What is the maximum supply current of the SN74LS688NSR? The maximum supply current is 65mA.
- Does the SN74LS688NSR include pull-up resistors on the Q inputs? Yes, it includes pull-up resistors on the Q inputs.
