SN74LS688DWR Texas Instruments Integrated Circuit (Small Outline Packages) In Stock
The SN74LS688DWR is an 8-bit identity/magnitude comparator with enable input, featuring cascadable architecture and 45pF load capacitance. From $1.53, in stock worldwide shipping.
- Manufacturer
- Texas Instruments
- Package
- Small Outline Packages
- Pin Count
- 20
- Lifecycle
- ACTIVE
- Datasheet
- SN74LS688DWR Datasheet PDF
- Category
- Integrated Circuit
- Price
- From $1.5300(MOQ 1)
- Temp Range
- ?°C to 70.0°C
- RoHS
- Compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
Key Features
- 8-bit identity comparator (P=Q) with active-low enable for easy bus expansion
- Cascadable design supports wider word comparisons without additional glue logic
- LS-family TTL with 24mA open-collector output drive and 45pF load capacitance
- Available in 20-pin SOIC (DWR) package for space-efficient PCB layouts
Applications
The SN74LS688DWR is widely used in address decoding and memory mapping circuits where microprocessors must compare address buses to predefined values. It is also applied in programmable logic controllers, industrial automation equipment, and data communication systems for identity checking and port selection. Its cascadable feature makes it ideal for building wide-word comparators in embedded control and digital signal processing applications.
Specifications
| Pbfree Code | Yes |
| YTEOL | 15 |
| Additional Feature | CASCADABLE |
| Family | LS |
| JESD-30 Code | R-PDSO-G20 |
| JESD-609 Code | e4 |
| Load Capacitance (CL) | 45pF |
| Logic IC Type | IDENTITY COMPARATOR |
| Max I(ol) | 0.024A |
| Number of Bits | 8 |
| Number of Functions | 8 |
| Output Characteristics | TOTEM-POLE |
| Output Polarity | INVERTED |
| Package Body Material | PLASTIC/EPOXY |
| Package Equivalence Code | SOP20,.4 |
| Package Shape | RECTANGULAR |
| Package Style | SMALL OUTLINE |
| Packing Method | TR |
| Peak Reflow Temperature (Cel) | 260 |
| Power Supply Current-Max (ICC) | 65mA |
| Prop. Delay@Nom-Sup | 23ns |
| Propagation Delay (tpd) | 23ns |
| Qualification Status | Not Qualified |
| Schmitt Trigger | YES |
| Supply Voltage-Max (Vsup) | 5.25V |
| Supply Voltage-Min (Vsup) | 4.85V |
| Supply Voltage-Nom (Vsup) | 5V |
| Surface Mount | YES |
| Technology | TTL |
| Temperature Grade | COMMERCIAL |
| Terminal Finish | Nickel/Palladium/Gold (Ni/Pd/Au) |
| Terminal Form | GULL WING |
| Terminal Pitch | 1.27mm |
| Terminal Position | DUAL |
| Time@Peak Reflow Temperature-Max (s) | 30 |
| Package | Small Outline Packages |
Compliance & Regulatory
| RoHS Status | Compliant |
| Lead-Free | Yes (Pb-Free) |
| Moisture Sensitivity Level | MSL 1 |
| ECCN | EAR99 |
| HTS Code | 8542.39.00.90 |
| Country of Origin | Malaysia |
Alternate & Equivalent Parts
Compatible alternatives and drop-in replacements for SN74LS688DWR:
Comparator, LS Series, 8-Bit, Inverted Output, TTL, PDSO20
Frequently Asked Questions
What is the SN74LS688DWR and what does it do?
The SN74LS688DWR is an 8-bit identity comparator IC from Texas Instruments. It compares two 8-bit words (P and Q) and asserts a low output when P equals Q. It includes an active-low enable pin for cascading multiple devices to support wider word comparisons in address decoding and bus matching applications.
What are the key electrical specifications of the SN74LS688DWR?
The SN74LS688DWR operates in the LS TTL logic family with a maximum output low current (I_OL) of 24mA, a load capacitance of 45pF, and is housed in a 20-pin SOIC package (JESD-30 code R-PDSO-G20). It is RoHS compliant (Pb-free, JESD-609 code e4) and has an estimated product life exceeding 15 years.
How do I cascade multiple SN74LS688DWR devices to compare more than 8 bits?
To cascade SN74LS688DWR devices for comparisons wider than 8 bits, connect the active-low enable output of one stage to the enable input of the next stage. When all lower-order bits match, the first stage enables the next, creating a ripple-enable chain. This cascadable architecture allows 16-bit, 24-bit, or wider comparisons with minimal additional components.
What packages are available for the SN74LS688DWR and what are alternatives?
The SN74LS688DWR is available in a 20-pin SOIC wide-body package (DWR suffix). Texas Instruments also offers this device in DIP and other surface-mount packages under the SN74LS688 family. Functional alternatives include the SN74HC688 (CMOS, lower power) and SN74ALS688 (advanced low-power Schottky) for designs requiring different power or speed characteristics.
Related Guides
ADSP-BF706BCPZ-4 Selection Guide: How to Choose a Blackfin+ DSP for Your Embedded Design
Compare ADSP-BF706BCPZ-4, BF548BBCZ-5A, and BF512BSWZ-4 on clock speed, memory, peripherals, and power to select the right Blackfin+ DSP.
Jun 10, 2026
ADC128S102 Selection Guide: How to Choose the Right 8-Channel 12-Bit SAR ADC
Compare ADC128S102 variants by supply voltage, temperature range, package, and qualification to pick the right 8-channel 12-bit SAR ADC for your design.
Jun 10, 2026
Common-Mode Filter + ESD Design Guide for High-Speed Differential Interfaces
How to choose between integrated CMF+ESD devices (ECMF02-2AMX6, ECMF02-4CMX8) and discrete ESD arrays for USB 2.0/3.x, MIPI, and HDMI interfaces—covering line count, bandwidth, clamping voltage, and package selection.
Jun 9, 2026
High-Capacitance MLCC Selection Guide: 22 µF vs 10 µF, X7R, 0805 to 1210
Learn how to choose between 22 µF and 10 µF X7R MLCCs (0805–1210). Covers DC bias derating, voltage rating, case size, and recommended Samsung CL-series parts.
Jun 9, 2026
Why Buy from FindMyChip
About Texas Instruments
Texas Instruments (TI) is a global semiconductor company headquartered in Dallas, Texas. TI designs and manufactures analog and embedded processing chips used in industrial, automotive, consumer, communications, and enterprise systems.
More from Texas Instruments
| Qty. | Unit Price | Ext. Price |
|---|---|---|
| 1+ | $2.3200 | $2.32 |
| 25+ | $1.7600 | $44.00 |
| 100+ | $1.6500 | $165.00 |
| 1000+ | $1.5300 | $1530.00 |
In Stock · 24h Response · Worldwide Shipping
Response within 24 hours · Worldwide shipping
“Their engineering team helped us find a pin-compatible alternative when our original MCU went EOL.”