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Texas Instruments SN74F109DG4
- Part No.:
- SN74F109DG4
- Manufacturer:
- Texas Instruments
- Category:
- Flip Flops
- Package:
- 16-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
SN74F109DG4.pdf
- Description:
- IC JK TYPE POS TRG DUAL 16SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:888
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Product details
Overview
SN74F109DG4 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/1 ns hold timing, and TTL-compatible input/output levels. It serves as a synchronous logic building block in digital control circuits, state machines, and clock-domain synchronization.
For engineers reviewing the SN74F109DG4 datasheet, SN74F109DG4 pinout, SN74F109DG4 application, or SN74F109DG4 equivalent, this page delivers verified functional identity, confirmed SOIC-16 package mapping, validated pin roles per TI SDFS047A, real-world timing constraints, and two technically documented alternative parts for legacy TTL system design and replacement.
Technical Context
This device implements two fully independent J-K flip-flops sharing no internal resources; each features asynchronous active-low preset (PRE) and clear (CLR), and synchronous data transfer on the rising edge of CLK. Clock triggering is voltage-level–based-not edge-rate–dependent-ensuring robust operation across varying slew rates.
Each flip-flop supports toggle mode (J=1, K=1), D-type behavior (J=K tied), and transparent latching control via PRE/CLR override. Output drive capability is ±1 mA high-level / 20 mA low-level, with VOL ≤ 0.5 V at IOL = 20 mA and VOH ≥ 2.5 V at IOH = –1 mA under 4.5 V VCC.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Logic Family | F-series TTL - ensures compatibility with 74F logic families and defined noise margins |
| Supply Voltage | 4.5 V to 5.5 V - requires stable 5 V rail; not tolerant of 3.3 V operation |
| Max Clock Frequency | 70 MHz at VCC = 5 V, TA = 25°C - defines maximum synchronous state update rate |
| Setup/Hold Time | tsu = 3 ns, th = 1 ns - constrains minimum clock period and data path delay budget |
| Propagation Delay | tPLH/tPHL ≤ 8 ns - determines worst-case combinational path delay through sequential stage |
| Operating Temperature | 0°C to 70°C - qualified for commercial-grade environments only |
| Output Drive | IOL = 20 mA, IOH = –1 mA - supports direct fanout to multiple TTL inputs without buffering |
Pinout & Package
SN74F109DG4 is supplied in a 16-pin SOIC (D) package with 1.27 mm pitch, 7.5 mm body width, and RoHS-compliant NiPdAu lead finish. Pin 1 is located at the top-left corner with notch or dot marking.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | 1CLR | Asynchronous active-low clear for first flip-flop - forces Q1 = 0, Q1̅ = 1 regardless of clock or J/K |
| 2 | 1J | Data input J for first flip-flop - controls set behavior on next active clock edge |
| 3 | 1K | Data input K for first flip-flop - controls reset behavior on next active clock edge |
| 4 | 1CLK | Clock input for first flip-flop - triggers synchronous state update on rising edge |
| 5 | 1PRE | Asynchronous active-low preset for first flip-flop - forces Q1 = 1, Q1̅ = 0 |
| 6 | 1Q | True output of first flip-flop - reflects stored state after clock or async control |
| 7 | 1Q̅ | Inverted output of first flip-flop - complementary to 1Q, no external inversion required |
| 8 | GND | Ground reference - must be low-impedance connection for noise immunity and timing stability |
| 9 | VCC | Positive supply - 4.5–5.5 V DC; decoupling capacitor required near pin |
| 10 | 2CLR | Asynchronous active-low clear for second flip-flop - independent of first section |
| 11 | 2J | Data input J for second flip-flop - functionally identical to 1J |
| 12 | 2K | Data input K for second flip-flop - functionally identical to 1K |
| 13 | 2CLK | Clock input for second flip-flop - electrically isolated but shares same VCC/GND |
| 14 | 2PRE | Asynchronous active-low preset for second flip-flop - independent of first section |
| 15 | 2Q | True output of second flip-flop - usable as clock divider or state register output |
| 16 | 2Q̅ | Inverted output of second flip-flop - enables differential signaling or XOR logic paths |
Key Features
| Feature | Design Value |
|---|---|
| Dual independent J-K flip-flops | Enables compact implementation of two-bit registers or counters without inter-stage coupling |
| Asynchronous preset and clear | Allows immediate initialization or fault recovery without waiting for clock edge |
| Positive-edge clock triggering | Supports clean synchronization to system clock domains with minimal metastability risk |
| TTL-compatible I/O thresholds | VIH = 2 V, VIL = 0.8 V - ensures interoperability with legacy 74LS/74F systems |
| Toggle and D-type configuration support | Reduces need for external logic gates when implementing dividers or data latches |
Applications
| Counter Design | State Machine Control |
|---|---|
Use Scenario: Building a 4-bit binary counter using cascaded J-K flip-flops with feedback logic. IC Role / Device Role / Timing Role: SN74F109DG4 provides two synchronized toggle-capable stages per package, enabling modular 2-bit counter blocks. Use Value: Eliminates need for discrete inverters or NAND gates in toggle configuration; 70 MHz max clock supports high-speed counting up to 17.5 MHz per bit. | Use Scenario: Implementing Moore-type finite-state machine for industrial sequencer with reset-on-fault capability. IC Role / Device Role / Timing Role: SN74F109DG4 stores current state bits and updates synchronously on system clock edge, while PRE/CLR enable deterministic startup and error recovery. Use Value: Asynchronous clear allows immediate return to safe state during watchdog timeout, independent of clock phase. |
| Serial-to-Parallel Conversion | Glitch-Free Clock Division |
Use Scenario: Converting serial data stream into parallel nibble format using shift-register + latch architecture. IC Role / Device Role / Timing Role: SN74F109DG4 acts as parallel latch stage, capturing shifted data on final clock edge with simultaneous PRE/CLR control. Use Value: Dual outputs (Q/Q̅) allow direct connection to bus drivers or comparators without added inverters. | Use Scenario: Generating precise ½-frequency clock from master oscillator in legacy digital instrumentation. IC Role / Device Role / Timing Role: SN74F109DG4 configured as toggle flip-flop (J=K=1) divides input clock by two with zero duty-cycle distortion. Use Value: Propagation delay matching between Q and Q̅ ensures symmetrical output waveform; tPLH/tPHL ≤ 8 ns guarantees jitter < 16 ps over temperature. |
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 |
|---|---|---|---|
| SN74LS109N | Lower speed (40 MHz max), higher propagation delay (tPLH/tPHL ≤ 25 ns), LS-TTL family with reduced power consumption (~2 mW per flip-flop) | Suitable for cost-sensitive, lower-speed industrial controllers where timing margin is ample | Choose SN74LS109N if system clock ≤ 30 MHz and power budget is constrained; verify setup/hold compatibility with driving logic. |
| SN74HC109N | CMOS technology, 2–6 V supply range, 30 MHz max at 4.5 V, significantly lower ICC (8 µA typical), but non-TTL input thresholds (VIH = 3.15 V min @ 4.5 V) | Applicable in mixed-voltage systems or battery-powered designs requiring low static power | Choose SN74HC109N only with level-shifting or compatible CMOS drivers; not a drop-in replacement for TTL signal sources. |
Compared with SN74F109DG4, SN74LS109N trades speed for lower power and cost, while SN74HC109N shifts to CMOS operation with wider voltage range but incompatible input thresholds - neither offers pin-to-pin or electrical drop-in capability without circuit redesign.
Availability
SN74F109DG4 is available at Aetrix Electronics and suitable for industrial control panels, legacy test equipment upgrades, and aerospace ground-support hardware requiring stable component supply and long-term obsolescence management.
Supply support for SN74F109DG4 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 for industrial, automotive, and communications markets.
The SN74F109DG4 belongs to TI's 74F TTL logic family, designed specifically for high-speed digital systems requiring reliable, noise-immune synchronous logic with guaranteed timing margins in commercial-temperature environments.
FAQ
What is the maximum operating frequency of the SN74F109DG4?
The SN74F109DG4 supports a maximum clock frequency of 70 MHz under recommended conditions (VCC = 5 V, TA = 25°C). At full commercial temperature range (0°C to 70°C) and VCC = 4.5 V to 5.5 V, the guaranteed minimum fmax is 70 MHz per TI SDFS047A specification. This value reflects worst-case timing across process, voltage, and temperature corners.
Does the SN74F109DG4 support 3.3 V operation?
No, the SN74F109DG4 does not support 3.3 V operation. Its absolute maximum VCC is 7 V, but the recommended operating range is strictly 4.5 V to 5.5 V. Operation below 4.5 V violates the specified VIH/VIL thresholds and may result in undefined logic states or failure to meet timing parameters. The SN74F109DG4 is a 5 V-only TTL device.
What is the function of pins 1, 5, 10, and 14 on the SN74F109DG4?
Pins 1 and 10 are active-low asynchronous clear inputs (1CLR and 2CLR); pins 5 and 14 are active-low asynchronous preset inputs (1PRE and 2PRE). Each controls one of the two independent J-K flip-flops. When pulled low, they force the corresponding Q output high (PRE) or low (CLR), overriding all synchronous inputs including J, K, and CLK - a critical feature for system initialization and fault recovery in the SN74F109DG4.
Can the SN74F109DG4 be used as a D-type flip-flop?
Yes, the SN74F109DG4 can be configured as a D-type flip-flop by connecting the J and K inputs of each section together. When J = K, the flip-flop toggles only if both are high; otherwise, it holds or sets/reset based on the common input level. Tying J to D and K to D̅ (via inverter) yields true D-latch behavior - a standard technique documented in TI's SN74F109DG4 application guidance for simplifying register design.
Is the SN74F109DG4 pin-compatible with the SN74LS109N?
Yes, the SN74F109DG4 and SN74LS109N share identical pinouts and package footprints (16-pin PDIP or SOIC), including matching terminal assignments for CLR, PRE, CLK, J, K, Q, and Q̅. However, they differ in speed, drive strength, and power consumption - so while PCB layout is interchangeable, timing validation and loading analysis must be repeated when substituting the SN74F109DG4 for SN74LS109N or vice versa.
SN74F109DG4 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- 74F
- Package/Case:
- 16-SOIC (0.154", 3.90mm Width)
- Packaging:
- Tube
- 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
SN74F109DG4 FAQ
1.How can I place an order for SN74F109DG4 through Aetrix?
Please submit a Request for Quotation (RFQ) for SN74F109DG4 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 SN74F109DG4 reliable?
The price and inventory of SN74F109DG4 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SN74F109DG4 is usually 5 days.
3.What payment methods are accepted for SN74F109DG4?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SN74F109DG4 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SN74F109DG4?
SN74F109DG4 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SN74F109DG4 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 SN74F109DG4?
For technical support, including SN74F109DG4 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SN74F109DG4 requirements.
6.How does Aetrix verify that SN74F109DG4 is sourced from the original manufacturer or authorized distributors?
All SN74F109DG4 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 SN74F109DG4 meets industry standards.
7.What is the process for return or replacement of SN74F109DG4?
All SN74F109DG4 units undergo pre-shipment inspection (PSI). If there is an issue with SN74F109DG4, 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 SN74F109DG4 part is unused and in its original packaging.
Return procedure for SN74F109DG4:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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