SN74LS109ANIn StockTexas Instruments
Texas Instruments SN74LS109AN is a dual J-K positive-edge-triggered flip-flop with set and reset inputs, operating at 4.75–5.25V with 25MHz max frequency in a 16-pin PDIP package. From $0.85, in stock, worldwide shipping.
- Manufacturer
- Texas Instruments
- Package
- Dual-In-Line Packages
- Pin Count
- 16
- Lifecycle
- ACTIVE
- Datasheet
- SN74LS109AN Datasheet PDF
- Category
- Integrated Circuit
- Price
- From $0.8452(MOQ 50)
- Temp Range
- ?°C to 70.0°C
- RoHS
- Compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
Key Features
- Dual J-K positive-edge-triggered flip-flop with inverted K input for versatile logic design
- Operates at up to 25 MHz max frequency with 4.75–5.25V supply voltage range
- 16-pin PDIP package with set and reset inputs for synchronous and asynchronous control
- RoHS compliant (Pb-free) with 15 pF load capacitance and 8 mA output low current
Applications
The SN74LS109AN is widely used in digital sequential logic circuits, including counters, shift registers, and state machines in industrial control and embedded systems. Its dual J-K flip-flop structure makes it ideal for frequency division, data storage, and synchronization tasks in microprocessor-based designs. The device is also commonly employed in legacy TTL-compatible systems requiring reliable clock-driven storage elements.
Specifications
| Pbfree Code | Yes |
| YTEOL | 15 |
| Additional Feature | INVERTED K INPUT |
| Family | LS |
| JESD-30 Code | R-PDIP-T16 |
| JESD-609 Code | e4 |
| Load Capacitance (CL) | 15pF |
| Logic IC Type | J-KBAR FLIP-FLOP |
| Max Frequency@Nom-Sup | 25000000Hz |
| Max I(ol) | 0.008A |
| Number of Bits | 2 |
| Number of Functions | 2 |
| Output Polarity | COMPLEMENTARY |
| Package Body Material | PLASTIC/EPOXY |
| Package Equivalence Code | DIP16,.3 |
| Package Shape | RECTANGULAR |
| Package Style | IN-LINE |
| Packing Method | TUBE |
| Power Supply Current-Max (ICC) | 15mA |
| Prop. Delay@Nom-Sup | 35ns |
| Propagation Delay (tpd) | 40ns |
| Qualification Status | Not Qualified |
| Schmitt Trigger | NO |
| Supply Voltage-Max (Vsup) | 5.25V |
| Supply Voltage-Min (Vsup) | 4.75V |
| Supply Voltage-Nom (Vsup) | 5V |
| Surface Mount | NO |
| Technology | TTL |
| Temperature Grade | COMMERCIAL |
| Terminal Finish | Nickel/Palladium/Gold (Ni/Pd/Au) |
| Terminal Form | THROUGH-HOLE |
| Terminal Pitch | 2.54mm |
| Terminal Position | DUAL |
| Trigger Type | POSITIVE EDGE |
| fmax-Min | 30MHz |
| Package | Dual-In-Line Packages |
Compliance & Regulatory
| RoHS Status | Compliant |
| Lead-Free | Yes (Pb-Free) |
| ECCN | EAR99 |
| HTS Code | 8542.39.00.90 |
| Country of Origin | Malaysia, Mexico |
Alternate & Equivalent Parts
Compatible alternatives and drop-in replacements for SN74LS109AN:
J-Kbar Flip-Flop, LS Series, 2-Func, Positive Edge Triggered, 2-Bit, Complementary Output, TTL, PDSO16
Frequently Asked Questions
What is the maximum operating frequency of the SN74LS109AN?
The SN74LS109AN supports a maximum operating frequency of 25 MHz at nominal supply voltage (5V). This makes it suitable for medium-speed digital logic applications such as counters and shift registers in embedded and industrial systems.
What package does the SN74LS109AN come in and what are its pin dimensions?
The SN74LS109AN comes in a 16-pin PDIP (Plastic Dual In-Line Package) through-hole package, which is compatible with standard breadboards and PCB through-hole footprints. The DIP package offers easy manual soldering and is widely used in prototyping and legacy system designs.
What are the key differences between the SN74LS109AN and a standard J-K flip-flop?
Unlike a standard J-K flip-flop, the SN74LS109AN features an inverted K input (K-bar), meaning the K pin is active-low. This simplifies certain logic configurations and allows the device to function as a D-type flip-flop by tying J and K-bar together. It also includes asynchronous preset and clear inputs for direct state control.
Is the SN74LS109AN RoHS compliant?
Yes, the SN74LS109AN is RoHS compliant and Pb-free (JESD-609 Code: e4), meeting environmental regulations for restriction of hazardous substances. It carries a YTEOL rating of 15 years for long-term supply availability.
What are typical applications for the SN74LS109AN?
The SN74LS109AN is commonly used in digital counters, frequency dividers, shift registers, and synchronous state machines. It is well-suited for TTL-level logic systems in industrial control, telecommunications, and legacy microprocessor-based designs requiring reliable edge-triggered storage.
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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 |
|---|---|---|
| 50+ | $1.8000 | $90.00 |
| 100+ | $1.6900 | $169.00 |
| 194+ | $1.5500 | $300.70 |
| 1000+ | $0.8452 | $845.20 |
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