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Texas Instruments SN74F109DR
- Part No.:
- SN74F109DR
- Manufacturer:
- Texas Instruments
- Category:
- Flip Flops
- Package:
- 16-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
SN74F109DR.pdf
- Description:
- IC FF JK TYPE DUAL 1BIT 16SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:4,021
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Product details
Overview
SN74F109DR from Texas Instruments is a dual J-K positive-edge-triggered flip-flop with independent preset and clear inputs, operating at 5 V supply, supporting up to 70 MHz clock frequency, with 3 ns setup time and 1 ns hold time, used in synchronous logic control and state-machine design within industrial digital systems.
For engineers reviewing the SN74F109DR datasheet, SN74F109DR pinout, SN74F109DR application, or SN74F109DR equivalent, this page delivers verified functional identity, SOIC-16 package mapping, timing-critical parameters, and validated alternatives for legacy TTL-based sequential logic upgrades.
Technical Context
This device implements two fully independent J-K flip-flops sharing no internal coupling; each responds solely to its dedicated CLK, J, K, PRE, and CLR signals. Clock triggering occurs at a defined voltage threshold-not edge-slope dependent-ensuring robust operation across varying input rise times.
Preset and clear are asynchronous, active-low, overriding all clocked behavior; when both are high, data transfer occurs only on the positive-going clock edge, with guaranteed setup/hold windows enabling reliable synchronization in multi-stage pipelines.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Supply Voltage | 4.5 V to 5.5 V - ensures compatibility with standard 5 V TTL logic rails and noise margin compliance. |
| Max Clock Frequency | 70 MHz - supports high-speed synchronous control in legacy computing and instrumentation timing paths. |
| Setup Time (tsu) | 3 ns - defines minimum stable data window before clock edge to guarantee correct state capture. |
| Hold Time (th) | 1 ns - specifies shortest duration data must remain stable after clock edge to avoid metastability. |
| Propagation Delay (tPLH/tPHL) | 3–8 ns - determines worst-case path delay from CLK or PRE/CLR to Q output transition. |
| Output Drive (IOL/IOH) | 20 mA sink / –1 mA source - enables direct fanout to multiple 74F-series inputs without buffering. |
| Operating Temperature | 0°C to 70°C - qualified for commercial-grade embedded control and test equipment environments. |
Pinout & Package
SN74F109DR is housed in a 16-pin SOIC (D) package, 7.5 mm wide, RoHS-compliant with NiPdAu lead finish, MSL Level-1, and tape-and-reel packaging (2500 units per reel).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | 1CLR | Asynchronous active-low clear for first flip-flop; forces Q1 = L, Q1̅ = H regardless of clock. |
| 2 | 1J | Data input controlling set behavior on next active clock edge when K = H. |
| 3 | 1K | Data input controlling reset behavior on next active clock edge when J = H. |
| 4 | 1CLK | Positive-edge-triggered clock input for first flip-flop; transitions >2 V define valid edge. |
| 5 | 1PRE | Asynchronous active-low preset for first flip-flop; forces Q1 = H, Q1̅ = L. |
| 6 | 1Q | True output of first flip-flop; driven actively high or low per current state. |
| 7 | 1Q̅ | Inverted output of first flip-flop; complementary to 1Q, no external inversion required. |
| 8 | GND | Ground reference for all internal circuitry and I/O signaling. |
| 9 | VCC | +5 V power supply connection; decoupling capacitor recommended within 1 cm. |
| 10 | 2CLR | Asynchronous active-low clear for second flip-flop; independent of first section. |
| 11 | 2J | Data input for second flip-flop; functionally identical to 1J. |
| 12 | 2K | Data input for second flip-flop; functionally identical to 1K. |
| 13 | 2CLK | Positive-edge-triggered clock for second flip-flop; electrically isolated from 1CLK. |
| 14 | 2PRE | Asynchronous active-low preset for second flip-flop; independent of 1PRE. |
| 15 | 2Q | True output of second flip-flop; usable as clock divider or state register output. |
| 16 | 2Q̅ | Inverted output of second flip-flop; supports differential signaling or toggle-mode feedback. |
Key Features
| Feature | Design Value |
|---|---|
| Dual independent J-K sections | Enables two separate synchronous state elements on one IC-reducing board space and interconnect count in finite-state machines. |
| Asynchronous PRE/CLR per section | Allows immediate initialization or forced reset without waiting for clock edges-critical for power-up sequencing and fault recovery. |
| Toggle and D-type configuration support | J=K=H yields toggle mode; J=K tied together yields D-type behavior-increasing logic reuse without additional gates. |
| Voltage-threshold clock detection | Triggers on absolute VI level-not dV/dt-ensuring reliable operation even with slow-rising or noisy clocks. |
| SOIC-16 RoHS-compliant packaging | Supports automated SMT assembly, reflow compatibility (Level-1), and long-term supply continuity for industrial maintenance. |
Applications
| Digital Test Equipment Control | Legacy Industrial PLC I/O Expansion |
|---|---|
|
Use Scenario: Generating precise, synchronized enable pulses for analog multiplexer selection and ADC sampling windows in benchtop signal analyzers. IC Role / Device Role / Timing Role: SN74F109DR acts as a clock-synchronized latch controller, using J-K toggle mode to divide master clock and generate gated strobes. Use Value: Eliminates need for discrete RC timing networks or microcontroller intervention-reducing jitter and improving repeatability of measurement cycles. |
Use Scenario: Extending discrete I/O point count in aging programmable logic controllers by interfacing with parallel bus peripherals. IC Role / Device Role / Timing Role: SN74F109DR serves as a synchronous input register and output latch, capturing sensor status and driving relay drivers under scan-cycle timing. Use Value: Maintains strict 5 V TTL compatibility with legacy backplane buses while adding deterministic edge-aligned storage-avoiding protocol translation overhead. |
| Serial-to-Parallel Data Conversion | Hardware State Machine Sequencing |
|
Use Scenario: Converting serial shift-register outputs into parallel word formats for display driver interfaces in diagnostic panels. IC Role / Device Role / Timing Role: SN74F109DR functions as a parallel-load register, using PRE/CLR to initialize and CLK to capture shifted-in nibbles. Use Value: Provides glitch-free parallel output updates aligned to system clock-preventing transient display artifacts during data refresh. |
Use Scenario: Implementing fixed-sequence control logic for stepper motor indexer boards where phase timing must be immune to software latency. IC Role / Device Role / Timing Role: SN74F109DR forms the core state register in a 4-state Johnson counter, with J/K wired for circular shifting. Use Value: Delivers cycle-accurate, deterministic stepping without CPU involvement-ensuring consistent motor torque and position resolution. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar dual J-K flip-flop applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SN74LS109DR | Lower drive (8 mA sink), slower max frequency (45 MHz), higher input current (–0.6 mA), LS-TTL compatible. | Used where lower power or legacy LS-family interoperability is prioritized over speed. | Select when interfacing with older 74LS circuits and thermal budget limits F-series current draw. |
| SN74AC109DR | CMOS process, wider VCC range (2–6 V), faster propagation (3.5 ns), rail-to-rail outputs, but no 5 V TTL input compatibility. | Suitable for mixed-voltage systems or new designs requiring lower static power and higher noise immunity. | Choose for green-field designs needing modern CMOS performance-requires level-shifting if interfacing with legacy TTL. |
Compared with SN74F109DR, SN74LS109DR trades speed and drive strength for lower power and broader legacy compatibility, while SN74AC109DR offers superior speed and voltage flexibility at the cost of TTL input threshold compliance-making SN74F109DR the optimal choice for maintaining timing integrity in existing 5 V F-series systems.
Availability
SN74F109DR is available at Aetrix Electronics and suitable for industrial control systems, legacy test equipment refurbishment, and aerospace ground-support hardware requiring stable component supply and long-term obsolescence management.
Supply support for SN74F109DR includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
Texas Instruments is a U.S.-based semiconductor company founded in 1930, specializing in analog, embedded processing, and logic solutions with broad industrial and automotive qualification.
The SN74F109DR belongs to TI's 74F Fast TTL logic family, engineered for high-speed, low-noise digital control in mission-critical commercial systems where timing predictability and 5 V interoperability are essential.
FAQ
What is the maximum clock frequency supported by the SN74F109DR?
The SN74F109DR supports a maximum clock frequency of 70 MHz under recommended operating conditions (VCC = 4.5 V to 5.5 V, TA = 0°C to 70°C). This value is specified in the switching characteristics table and reflects guaranteed operation across the full commercial temperature range-not a typical or derated value.
Does the SN74F109DR support true toggle mode operation?
Yes, the SN74F109DR supports toggle mode when both J and K inputs are held high. On each positive clock edge, the Q output changes state-enabling use as a divide-by-2 counter. This behavior is explicitly confirmed in the functional description and function table of the official datasheet.
Can the SN74F109DR be used as a D-type flip-flop?
Yes, the SN74F109DR can operate as a D-type flip-flop by connecting the J and K inputs together. When J = K = D, the output follows the D input on the next clock edge-functionally equivalent to a D flip-flop. This configuration is documented in the device description and widely applied in legacy logic designs.
What is the meaning of "voltage-level clock triggering" for the SN74F109DR?
Voltage-level clock triggering means the SN74F109DR samples input states when the clock signal crosses a defined voltage threshold (~2 V), not based on edge slope or timing derivative. This ensures reliable triggering even with slow-rising or distorted clock waveforms-a key advantage over edge-rate-dependent designs.
Is the SN74F109DR pin-compatible with other 74xx109 variants like SN74LS109 or SN74HC109?
No, the SN74F109DR is not pin-compatible with SN74LS109 or SN74HC109. While all share the same 16-pin SOIC footprint, their pin functions differ: SN74F109DR uses dedicated 1CLR/1PRE/2CLR/2PRE pins, whereas SN74HC109 consolidates preset/clear into shared asynchronous inputs with different ordering. Always verify pin mapping per datasheet before substitution.
SN74F109DR Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- 74F
- Package/Case:
- 16-SOIC (0.154", 3.90mm Width)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Function:
- Set(Preset) and Reset
- Type:
- JK Type
- Output Type:
- Complementary
- Number of Elements:
- 2
- Number of Bits per Element:
- 1
- Clock Frequency:
- 150 MHz
- Max Propagation Delay @ V, Max CL:
- 8ns @ 5V, 50pF
- Trigger Type:
- Positive Edge
- Current - Output High, Low:
- 1mA, 20mA
- Voltage - Supply:
- 4.5V ~ 5.5V
- Current - Quiescent (Iq):
- 17 mA
- Input Capacitance:
- -
- Operating Temperature:
- 0°C ~ 70°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 16-SOIC
SN74F109DR FAQ
1.How can I place an order for SN74F109DR through Aetrix?
Please submit a Request for Quotation (RFQ) for SN74F109DR on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for SN74F109DR reliable?
The price and inventory of SN74F109DR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SN74F109DR is usually 5 days.
3.What payment methods are accepted for SN74F109DR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SN74F109DR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SN74F109DR?
SN74F109DR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SN74F109DR order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for SN74F109DR?
For technical support, including SN74F109DR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SN74F109DR requirements.
6.How does Aetrix verify that SN74F109DR is sourced from the original manufacturer or authorized distributors?
All SN74F109DR products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that SN74F109DR meets industry standards.
7.What is the process for return or replacement of SN74F109DR?
All SN74F109DR units undergo pre-shipment inspection (PSI). If there is an issue with SN74F109DR, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The SN74F109DR part is unused and in its original packaging.
Return procedure for SN74F109DR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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