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Texas Instruments SN74LVC821DBLE
- Part No.:
- SN74LVC821DBLE
- Manufacturer:
- Texas Instruments
- Category:
- Flip Flops
- Package:
- -
- Datasheet:
-
SN74LVC821DBLE.pdf
- Description:
- IC FF D-TYPE SNGL 10BIT 24SSOP
- Quantity:
- Payment:
- Shipping:
Inventory:5,000
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Product details
Overview
SN74LVC821DBLE from Texas Instruments is a 10-bit bus-interface D-type flip-flop with 3-state outputs, designed for 1.65 V to 3.6 V operation. It features edge-triggered clocking (CLK), buffered output-enable (OE), true-Q outputs, and supports mixed-mode signal operation with 5-V-tolerant inputs. It is used in bidirectional bus drivers, I/O port expansion, and working registers in industrial control and embedded computing systems.
For engineers reviewing the SN74LVC821DBLE datasheet, SN74LVC821DBLE pinout, SN74LVC821DBLE application, or SN74LVC821DBLE equivalent, key selection criteria include 3-state drive capability, 10-bit synchronous latching, 5.5-V input tolerance, Ioff partial-power-down support, and SSOP-24 package compatibility for space-constrained PCB layouts.
Technical Context
This device implements ten independent positive-edge-triggered D-type flip-flops with common clock (CLK) and output-enable (OE) control. Each flip-flop captures data on the rising edge of CLK and presents it at the corresponding Q output, while OE independently places all ten outputs into high-impedance state without affecting internal latch operation.
It supports mixed-voltage interfacing: inputs accept up to 5.5 V regardless of VCC (1.65–3.6 V), enabling direct connection to 5-V logic in 3.3-V systems. The Ioff feature disables outputs during power-down, preventing backflow current when VCC = 0 V - critical for hot-swap and partial-power-down architectures.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCC Range | 1.65 V to 3.6 V - enables interoperability across 1.8-V, 2.5-V, and 3.3-V logic domains. |
| Input Voltage Tolerance | Up to 5.5 V - allows direct interface with legacy 5-V peripherals without level shifters. |
| Max Propagation Delay (tpd) | 7.3 ns at VCC = 3.3 V - supports >100 MHz clock rates in high-speed bus buffering. |
| Output Drive Strength | ±24 mA at VCC = 3.0 V - drives heavy capacitive loads (e.g., long traces, multiple inputs) without external buffers. |
| Ioff Current | ±10 µA at VI/VO = 5.5 V - ensures safe isolation during partial power-down, meeting JESD78 requirements. |
| Operating Temperature | –40°C to +85°C - qualified for industrial-grade embedded applications. |
| ESD Rating | 2000-V HBM - provides robust handling in manufacturing and field environments. |
Pinout & Package
SN74LVC821DBLE is housed in a 24-pin SSOP (Shrink Small-Outline Package) with 0.65 mm lead pitch, JEDEC MO-150 compliant, body dimensions 8.20 mm × 3.50 mm × 1.75 mm (max height). Pin 1 is located at top-left corner with notch or dot marking.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | OE (Output Enable) | Active-low control: drives all 10 Q outputs to high-impedance when high; normal logic levels when low. |
| 2–11 | 1D–10D | Data inputs for each of ten D-type flip-flops; sampled on rising CLK edge. |
| 12 | GND | Ground reference for all internal circuitry and I/O structures. |
| 13–22 | 1Q–10Q | True outputs; reflect stored D-input value after CLK edge, unless OE disables them. |
| 23 | VCC | Primary supply rail (1.65–3.6 V); powers core logic and output drivers. |
| 24 | CLK | Global clock input; positive-edge sensitive; synchronizes all ten flip-flops simultaneously. |
Key Features
| Feature | Design Value |
|---|---|
| Mixed-mode signal operation | 5-V-tolerant inputs enable seamless integration between 3.3-V system logic and 5-V peripherals without external translators. |
| Ioff partial-power-down support | Prevents damaging current backflow when VCC = 0 V, allowing safe insertion/removal in live backplanes or modular systems. |
| High-drive 3-state outputs | ±24 mA drive strength at 3.0 V ensures reliable signal integrity on loaded buses, eliminating need for external line drivers. |
| Low ground bounce (VOLP) | <0.8 V typical at VCC = 3.3 V - reduces noise coupling into adjacent signals and improves timing margin. |
| Latch-up immunity | >250 mA per JESD17 - guarantees robust operation under transient overvoltage or ESD stress conditions. |
Applications
| Industrial PLC I/O Expansion | Embedded Memory Interface Buffer |
|---|---|
Use Scenario: Expanding digital input/output capacity in programmable logic controllers using shared backplane buses. IC Role / Device Role / Timing Role: 10-bit synchronous latch and 3-state bus driver; isolates CPU bus from field-side I/O modules during configuration or fault events. Use Value: Enables hot-swappable I/O modules via Ioff protection and eliminates bus contention with OE-controlled high-Z state. |
Use Scenario: Interfacing microcontroller parallel memory bus to external SRAM or FPGA configuration memory with voltage-level mismatch. IC Role / Device Role / Timing Role: Bidirectional data register and level translator; holds address/data during memory access cycles synchronized to system clock. Use Value: Supports 5-V memory devices on 3.3-V MCU bus via 5.5-V-tolerant inputs and precise setup/hold timing (tsu = 1.9 ns, th = 1.5 ns). |
| Test Equipment Digital Pattern Generator | Automotive Body Control Module |
Use Scenario: Generating deterministic multi-bit stimulus patterns for functional testing of digital ASICs or FPGAs. IC Role / Device Role / Timing Role: Synchronized 10-bit pattern register; CLK aligns all bits to test clock edge, OE enables/disables pattern injection onto DUT bus. Use Value: Achieves sub-2 ns timing skew across all 10 bits (tpd = 7.3 ns max), ensuring deterministic vector delivery. |
Use Scenario: Managing discrete sensor/actuator signals (e.g., door lock status, window position) in centralized vehicle body controller. IC Role / Device Role / Timing Role: Input capture register and output driver for GPIO expansion; latches sensor states on vehicle wake-up interrupt edge. Use Value: Industrial temperature range (–40°C to +85°C) and 2000-V HBM ESD rating ensure reliability in harsh automotive cabin environments. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar 10-bit bus-interface flip-flop applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SN74LVC821ADBR | Same die, identical electrical specs, SSOP-24 package; active production status vs. SN74LVC821DBLE's obsolete status. | Direct drop-in replacement with guaranteed long-term availability and RoHS/Green compliance. | Select SN74LVC821ADBR for new designs requiring full production support and traceable sourcing. |
| SN74LVC821APWR | TSSOP-24 package (4.4 mm width vs. SSOP's 5.3 mm); same logic function, timing, and voltage specs; slightly higher θJA (88°C/W vs. 63°C/W). | Better suited for high-density layouts where board area is constrained; thermal derating required above 50 mW average power. | Choose SN74LVC821APWR when footprint reduction outweighs thermal margin trade-off in compact consumer electronics. |
Compared with SN74LVC821DBLE, SN74LVC821ADBR offers assured supply continuity and full documentation support, while SN74LVC821APWR trades package size for marginally reduced thermal performance - both retain identical functionality, timing, and I/O behavior for seamless migration.
Availability
SN74LVC821DBLE is available at Aetrix Electronics and suitable for industrial control systems, embedded memory interfaces, and automotive body electronics requiring stable component supply and long-lifecycle support.
Supply support for SN74LVC821DBLE 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 global semiconductor leader specializing in analog, embedded processing, and logic solutions, with decades of expertise in high-reliability interface and timing ICs.
The SN74LVC821DBLE belongs to TI's LVC logic family, engineered for low-voltage, high-speed bus interfacing in mixed-signal systems - emphasizing voltage translation, noise immunity, and power-aware design for industrial and automotive applications.
FAQ
What is the operating voltage range for SN74LVC821DBLE?
The SN74LVC821DBLE operates from 1.65 V to 3.6 V on VCC. Its inputs tolerate up to 5.5 V regardless of VCC level, enabling mixed-voltage system interfacing. This specification is verified across –40°C to +85°C and documented in TI's SCAS304J datasheet Section 5 (Recommended Operating Conditions).
Is SN74LVC821DBLE pin-compatible with other packages in the SN74LVC821A family?
Yes - SN74LVC821DBLE shares identical pinout and logic function with all SN74LVC821A variants (e.g., DW, PW, DGV, NS), including the same 24-pin arrangement, CLK/OE/D/Q signal mapping, and power/ground locations. Mechanical differences exist only in package dimensions and thermal characteristics, not connectivity.
Does SN74LVC821DBLE support partial power-down operation?
Yes, SN74LVC821DBLE incorporates Ioff circuitry that disables outputs when VCC = 0 V, limiting current backflow to ±10 µA (per datasheet Section 6.5). This allows safe use in hot-swap or modular systems where subsystems may be powered independently.
What is the maximum clock frequency supported by SN74LVC821DBLE?
SN74LVC821DBLE supports up to 150 MHz clock frequency at VCC ≥ 2.7 V, as specified in the Timing Requirements table (Section 3). At 3.3 V, propagation delay is 7.3 ns, yielding a practical maximum toggle rate exceeding 68 MHz under load - sufficient for most industrial bus and control applications.
How does the output-enable (OE) function behave during power-up?
During power-up, OE should be tied to VCC via a pullup resistor to ensure outputs remain in high-impedance until firmware initializes the device. The minimum resistor value depends on the driver's sink capability; TI recommends ≥10 kΩ for standard CMOS drivers, as detailed in Section 7.2 of the SN74LVC821A datasheet.
SN74LVC821DBLE Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- 74LVC
- 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:
- -
SN74LVC821DBLE FAQ
1.How can I place an order for SN74LVC821DBLE through Aetrix?
Please submit a Request for Quotation (RFQ) for SN74LVC821DBLE 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 SN74LVC821DBLE reliable?
The price and inventory of SN74LVC821DBLE are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SN74LVC821DBLE is usually 5 days.
3.What payment methods are accepted for SN74LVC821DBLE?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SN74LVC821DBLE transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SN74LVC821DBLE?
SN74LVC821DBLE orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SN74LVC821DBLE 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 SN74LVC821DBLE?
For technical support, including SN74LVC821DBLE datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SN74LVC821DBLE requirements.
6.How does Aetrix verify that SN74LVC821DBLE is sourced from the original manufacturer or authorized distributors?
All SN74LVC821DBLE 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 SN74LVC821DBLE meets industry standards.
7.What is the process for return or replacement of SN74LVC821DBLE?
All SN74LVC821DBLE units undergo pre-shipment inspection (PSI). If there is an issue with SN74LVC821DBLE, 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 SN74LVC821DBLE part is unused and in its original packaging.
Return procedure for SN74LVC821DBLE:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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