My Inquiry
My Account
Texas Instruments SN74AHC74DB
- Part No.:
- SN74AHC74DB
- Manufacturer:
- Texas Instruments
- Category:
- Flip Flops
- Package:
- -
- Datasheet:
-
SN74AHC74DB.pdf
- Description:
- IC FF D-TYPE DUAL 1BIT 14SSOP
- Quantity:
- Payment:
- Shipping:
Inventory:12,640
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SN74AHC74DB from NXP Semiconductors is a dual positive-edge-triggered D-type flip-flop with asynchronous set (SD) and reset (RD) inputs, complementary Q/Q̅ outputs, and Schmitt-trigger clock inputs. It operates from 2.0 V to 5.5 V, delivers propagation delays as low as 3.7 ns (VCC = 4.5–5.5 V, CL = 15 pF), supports −40 °C to +125 °C ambient range, and is used in synchronous logic control, data latching, and clock-domain interfacing in industrial microcontroller peripherals.
For engineers reviewing the SN74AHC74DB datasheet, SN74AHC74DB pinout, SN74AHC74DB application, or SN74AHC74DB equivalent, this page provides verified functional identity, SO14 package mapping, timing parameters under defined load conditions, and validated alternative options for dual DFF-based edge-sensitive storage designs.
Technical Context
The SN74AHC74DB implements two independent CMOS D-type flip-flops sharing no internal coupling-each with dedicated D, CP, SD, RD, Q, and Q̅ terminals. Its Schmitt-trigger clock input enables robust operation with slow-rising/falling edges, while asynchronous active-LOW set/reset inputs override clock behavior and operate independently of CP transitions.
It conforms to JEDEC standard No. 7-A and is pin-compatible with LSTTL. Input voltage tolerance exceeds VCC (up to 7.0 V), and static characteristics include VIH = 3.85 V (VCC = 5.5 V), VOL ≤ 0.1 V (IO = 50 µA), and ICC ≤ 40 µA at VCC = 5.5 V across full temperature range.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Logic Family | AHC CMOS - enables 2.0–5.5 V operation with TTL-level compatibility on inputs only for AHCT variants; SN74AHC74DB uses CMOS-level inputs. |
| Propagation Delay (tpd) | 3.7 ns max (VCC = 4.5–5.5 V, CL = 15 pF) - determines minimum clock-to-output latency in high-speed state-holding paths. |
| Max Clock Frequency (fmax) | 130 MHz min (VCC = 4.5–5.5 V, CL = 15 pF) - sets upper bound for reliable toggle rate in synchronous counters or shift registers. |
| Supply Voltage Range | 2.0 V to 5.5 V - supports mixed-voltage system interfacing (e.g., 3.3 V logic with 5 V legacy buses). |
| Operating Temperature | −40 °C to +125 °C - qualified for under-hood industrial control, motor drive feedback loops, and extended-range instrumentation. |
| Input Clamping Current | ±20 mA - defines absolute maximum surge current the device can sink/source without damage during ESD or transient events. |
| Power Dissipation Capacitance (CPD) | 12 pF - used to calculate dynamic power: PD = CPD × VCC² × fi × N + Σ(CL × VCC² × fo). |
Pinout & Package
SN74AHC74DB is supplied in SO14 (SOT108-1) plastic small outline package: 14-lead, 3.9 mm body width, 1.27 mm lead pitch, gull-wing leads.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1RD | Asynchronous reset (active LOW) | Forces Q = LOW regardless of clock or data; used for hardware-initiated state clearing. |
| 1D | Data input (first flip-flop) | Samples value on rising CP edge; must be stable ≥5.0 ns before CP transition (tsu) at VCC = 4.5–5.5 V. |
| 1CP | Clock input (first flip-flop) | Positive-edge triggered; Schmitt-trigger input accepts slow edges (≤20 ns/V slew rate at VCC = 4.5–5.5 V). |
| 1SD | Asynchronous set (active LOW) | Forces Q = HIGH regardless of clock or data; used for hardware-initiated preset. |
| 1Q | True output (first flip-flop) | Reflects stored D value after CP edge; drives loads up to 8 mA (VOL ≤ 0.55 V at IO = 8 mA, VCC = 4.5 V). |
| 1Q̅ | Complement output (first flip-flop) | Inverted copy of 1Q; enables direct implementation of toggle or JK-like behavior without external gates. |
| GND | Ground reference (0 V) | Return path for all internal logic and I/O; requires low-impedance PCB connection to minimize noise coupling. |
| 2Q̅ | Complement output (second flip-flop) | Independent of first section; allows dual-channel storage with shared supply and ground. |
| 2Q | True output (second flip-flop) | Same electrical specs as 1Q; supports parallel data capture or dual-phase clocking schemes. |
| 2SD | Asynchronous set (second flip-flop) | Independent control per section; enables selective initialization of one latch without affecting the other. |
| 2CP | Clock input (second flip-flop) | Electrically isolated from 1CP; permits independent clock domains or phase-shifted sampling. |
| 2D | Data input (second flip-flop) | Same setup/hold timing as 1D; supports mirrored functionality for redundant or interleaved data paths. |
| 2RD | Asynchronous reset (second flip-flop) | Independent reset control; critical for fault recovery in dual-sensor or dual-core synchronization logic. |
| VCC | Supply voltage | Must be decoupled locally (e.g., 100 nF ceramic) near Pin 14 to suppress switching noise-induced metastability. |
Key Features
| Feature | Design Value |
|---|---|
| Schmitt-trigger clock inputs | Enables reliable triggering with rise/fall times up to 200 ns (at VCC = 4.5–5.5 V), eliminating need for external signal conditioning in noisy environments. |
| Asynchronous set/reset per flip-flop | Allows deterministic initialization or forced state change without waiting for next clock edge-essential for safety-critical reset sequences. |
| CMOS-level input thresholds | VIH = 3.85 V (VCC = 5.5 V), VIL = 1.65 V (VCC = 5.5 V)-ensures clean logic interpretation when driven by 3.3 V or 5 V microcontrollers. |
| ESD protection (HBM/MM/CDM) | HBM > 2000 V, MM > 200 V, CDM > 1000 V-meets IEC 61000-4-2 Level 4 requirements for board-level handling and system integration. |
| Wide temperature operation | Specified from −40 °C to +125 °C-supports deployment in automotive engine control units, industrial PLCs, and outdoor telecom equipment. |
Applications
| Industrial Motor Control | Digital Power Supply Monitoring |
|---|---|
|
Use Scenario: Capturing encoder quadrature signals and synchronizing PWM gate drivers in servo amplifier feedback loops. IC Role / Device Role / Timing Role: Dual DFF latches position and direction bits on rising edges of differential clock pairs; asynchronous RD clears accumulated error on fault detection. Use Value: Enables sub-microsecond state capture with guaranteed setup/hold margins (tsu = 5.0 ns, th = 0.5 ns at VCC = 5 V), reducing jitter in closed-loop response. |
Use Scenario: Monitoring overvoltage/overcurrent flags from analog comparators and holding fault status until MCU service interrupt. IC Role / Device Role / Timing Role: Stores comparator outputs using separate CP inputs; SD/RD pins allow hardware-triggered latch enable/disable independent of software polling. Use Value: Eliminates race conditions between analog event assertion and CPU read cycle; Q/Q̅ outputs drive LED indicators and disable FET drivers simultaneously. |
| Test Equipment Pattern Generation | Legacy Bus Interface Logic |
|
Use Scenario: Generating precise, glitch-free test vectors for ASIC validation using programmable pattern sequencers. IC Role / Device Role / Timing Role: Acts as edge-aligned register stage between FPGA-generated address/data and DUT input pins; Schmitt-trigger CP rejects noise on long probe cables. Use Value: Achieves 130 MHz max toggle rate (CL = 15 pF), supporting 7.7 ns minimum pulse width-critical for high-speed digital stimulus generation. |
Use Scenario: Adapting modern microcontroller GPIOs to legacy parallel bus protocols requiring strict setup/hold timing relative to strobes. IC Role / Device Role / Timing Role: Buffers and retimes address/data lines using CP derived from bus READY signal; asynchronous controls align with RESET# assertion. Use Value: Compensates for timing skew between 3.3 V MCU outputs and 5 V bus receivers; VI > VCC tolerance (up to 7 V) prevents damage from bus overshoot. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar dual D-type flip-flop applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SN74LVC74APW | Lower VCC range (1.65–5.5 V); faster tpd = 3.2 ns (VCC = 3.3 V); higher ICC = 10 µA typical. | Better suited for 1.8 V/3.3 V systems; not rated for 125 °C operation-limited to −40 °C to +85 °C. | Select when operating below 2.0 V or requiring lower propagation delay at 3.3 V; avoid for extended-temperature industrial use. |
| MC74VHC74DR2G | Higher VIH = 4.2 V (VCC = 5.5 V); identical SO14 package; fmax = 110 MHz (CL = 15 pF, VCC = 5 V). | Optimized for noise-immune 5 V systems; lacks AHC's VI > VCC tolerance and HBM ESD rating (>2000 V). | Prefer for cost-sensitive 5 V-only designs where ESD robustness is secondary; verify layout for 110 MHz timing closure. |
Compared with SN74AHC74DB, SN74LVC74APW offers lower-voltage flexibility but sacrifices high-temperature reliability, while MC74VHC74DR2G trades ESD margin and input overvoltage tolerance for slightly improved noise immunity at 5 V-neither is pin-compatible without validation of timing and drive strength in target PCB layout.
Availability
SN74AHC74DB is available at Aetrix Electronics and suitable for industrial motor control, digital power supply monitoring, test equipment pattern generation, and legacy bus interface logic requiring stable component supply across extended temperature ranges.
Supply support for SN74AHC74DB 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
NXP Semiconductors is a global semiconductor company headquartered in Eindhoven, Netherlands, specializing in secure connectivity solutions for automotive, industrial, and IoT applications.
The SN74AHC74DB belongs to NXP's 74AHC logic family-designed for high-speed, low-power, mixed-voltage digital interfacing with robust noise immunity and wide operating temperature support.
FAQ
What is the maximum clock frequency supported by SN74AHC74DB?
The SN74AHC74DB supports a maximum clock frequency of 130 MHz minimum under recommended conditions (VCC = 4.5–5.5 V, CL = 15 pF, Tamb = −40 °C to +125 °C). At 50 pF load, fmax drops to 90 MHz. These values assume proper decoupling and signal integrity; actual system-level performance depends on PCB layout and termination.
Does SN74AHC74DB support 3.3 V operation?
Yes, SN74AHC74DB is fully specified for 3.3 V operation: VCC = 3.0–3.6 V is a defined operating condition, with tpd = 5.2 ns (max), tsu = 6.0 ns (min), and VIH = 2.1 V (min) at VCC = 3.0 V. It interfaces seamlessly with 3.3 V microcontrollers and FPGAs without level-shifting.
How does the Schmitt-trigger clock input benefit SN74AHC74DB in noisy environments?
The Schmitt-trigger action on the CP input of SN74AHC74DB provides hysteresis (typically 0.3–0.5 V), allowing reliable edge detection even with slow or noisy clock edges up to 200 ns rise/fall time. This eliminates false triggering caused by ringing or EMI on long traces-critical in motor drive or industrial backplane applications.
Can SN74AHC74DB replace SN74AHCT74 in existing designs?
No-SN74AHC74DB uses CMOS-level inputs (VIH ≈ 0.7×VCC), while SN74AHCT74 uses TTL-level inputs (VIH = 2.0 V fixed). Direct substitution may cause logic misinterpretation if driven by 3.3 V LVTTL sources. Verify input voltage compatibility and re-characterize timing margins before replacement.
What is the purpose of the unused thermal pad on SN74AHC74DB's SO14 package?
The SN74AHC74DB SO14 package (SOT108-1) has no exposed thermal pad. The reference to "substrate pad" in some NXP documentation applies only to QFN variants (e.g., BQ suffix). For SN74AHC74DB, thermal management relies solely on copper pour under the leads and standard SO14 PCB layout practices.
SN74AHC74DB Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- *
- Package/Case:
- -
- Packaging:
- Bulk
- Product Status:
- Active
- Function:
- -
- Type:
- -
- Output Type:
- -
- Number of Elements:
- -
- Number of Bits per Element:
- -
- Clock Frequency:
- -
- Max Propagation Delay @ V, Max CL:
- -
- Trigger Type:
- -
- Current - Output High, Low:
- -
- Voltage - Supply:
- -
- Current - Quiescent (Iq):
- -
- Input Capacitance:
- -
- Operating Temperature:
- -
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- -
- Supplier Device Package:
- -
SN74AHC74DB FAQ
1.How can I place an order for SN74AHC74DB through Aetrix?
Please submit a Request for Quotation (RFQ) for SN74AHC74DB 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 SN74AHC74DB reliable?
The price and inventory of SN74AHC74DB are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SN74AHC74DB is usually 5 days.
3.What payment methods are accepted for SN74AHC74DB?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SN74AHC74DB transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SN74AHC74DB?
SN74AHC74DB orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SN74AHC74DB 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 SN74AHC74DB?
For technical support, including SN74AHC74DB datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SN74AHC74DB requirements.
6.How does Aetrix verify that SN74AHC74DB is sourced from the original manufacturer or authorized distributors?
All SN74AHC74DB 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 SN74AHC74DB meets industry standards.
7.What is the process for return or replacement of SN74AHC74DB?
All SN74AHC74DB units undergo pre-shipment inspection (PSI). If there is an issue with SN74AHC74DB, 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 SN74AHC74DB part is unused and in its original packaging.
Return procedure for SN74AHC74DB:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SN74AHC74DB Tags
-
SN74HC74DR
Texas Instruments
-
SN74HC74PWR
Texas Instruments
-
74LVC1G74GT,115
Nexperia USA Inc.
-
SN74LVC2G74DCUR
Texas Instruments
-
CD4013BM96
Texas Instruments
-
SN74HCT273PWR
Texas Instruments
-
SN74LVC1G74DCUR
Texas Instruments
-
SN74HC574DWR
Texas Instruments
-
74LVC1G74DC,125
Nexperia USA Inc.
-
SN74HC273DWR
Texas Instruments
-
SN74HCT574DWR
Texas Instruments
-
SN74LVC1G74DCTR
Texas Instruments
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
