My Inquiry
My Account
Texas Instruments SN74HC245DBRG4
- Part No.:
- SN74HC245DBRG4
- Manufacturer:
- Texas Instruments
- Package:
- 20-SSOP (0.209", 5.30mm Width)
- Datasheet:
-
SN74HC245DBRG4.pdf
- Description:
- IC TXRX NON-INVERT 6V 20SSOP
- Quantity:
- Payment:
- Shipping:
Inventory:2,497
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SN74HC245DBRG4 from Texas Instruments is an octal bus transceiver with 3-state outputs, designed for asynchronous bidirectional data transfer between two 8-bit buses (A↔B) in systems requiring level-shifting, bus isolation, or load driving up to 15 LSTTL loads. It operates from 2 V to 6 V, delivers ±6 mA output drive at 5 V, features typical propagation delay of 12 ns (CL = 50 pF), and consumes ≤80 μA ICC - enabling use in low-power industrial control backplanes and embedded I/O expansion interfaces.
For engineers reviewing the SN74HC245DBRG4 datasheet, SN74HC245DBRG4 pinout, SN74HC245DBRG4 application, or SN74HC245DBRG4 equivalent, key selection criteria include its 20-pin SSOP package, DIR/OE dual-control logic, 3-state bus isolation capability, and compatibility with mixed-voltage 3.3 V/5 V system interconnects where controlled signal direction and low quiescent current are critical.
Technical Context
The SN74HC245DBRG4 implements a CMOS-based octal transceiver architecture with independent direction (DIR) and output-enable (OE) inputs, supporting A→B or B→A data flow per channel. Its balanced output drive and slow edge rates minimize ringing on transmission lines, making it suitable for noise-sensitive board-level interconnects.
It operates across –40°C to +85°C with absolute maximum VCC of 7 V and ESD ratings of ±3000 V HBM. The device enters high-impedance state when OE is high, and direction is determined solely by DIR logic level - no internal latching or clocking required.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCC Range | 2 V to 6 V - supports interoperability between 3.3 V and 5 V domains without level shifters |
| tpd (CL = 50 pF) | 12 ns typical at 6 V - enables sub-25 MHz bus operation with timing margin |
| Output Drive | ±6 mA at 5 V - sufficient to directly drive 15 LSTTL loads or interface with legacy TTL peripherals |
| ICC (Max) | 80 μA - ensures minimal power impact in always-on system management or standby I/O buffers |
| Input Current | ≤1 μA max - eliminates need for external pull-up/down resistors on DIR/OE in most configurations |
| ESD Rating | ±3000 V HBM - meets industrial handling requirements without additional protection circuitry |
| Operating Temp | –40°C to +85°C - qualified for commercial and extended-temperature embedded applications |
Pinout & Package
SN74HC245DBRG4 is housed in a 20-pin SSOP (Shrink Small Outline Package) with 0.65 mm pitch, body size 7.20 mm × 5.30 mm, RoHS-compliant NiPdAu lead finish, and MSL Level-1 rating for unlimited floor life.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (DIR) | Direction Control Input | Low = B→A data flow; High = A→B data flow - determines real-time bus direction without clock or latch |
| 2–9 (A1–A8) | Port A I/O Terminals | Bi-directional data pins for first bus segment; high-impedance when OE = High or power-off |
| 10 (GND) | Ground Reference | Primary return path for all internal logic and output currents - must be low-impedance connection |
| 11–18 (B1–B8) | Port B I/O Terminals | Bi-directional data pins for second bus segment; electrically isolated from A-side when OE = High |
| 19 (OE) | Output Enable Input | Active-Low control: Low = transceiver enabled; High = all A/B outputs in high-Z - enables bus arbitration |
| 20 (VCC) | Power Supply | Single supply input (2–6 V); requires local 0.1 μF bypass capacitor placed adjacent to pin |
Key Features
| Feature | Design Value |
|---|---|
| Wide VCC range (2–6 V) | Enables direct interfacing between 3.3 V microcontrollers and 5 V peripheral buses without external level translators |
| 3-State outputs with dual control | DIR selects direction; OE independently disables both ports - supports time-multiplexed bus sharing and hot-swap isolation |
| Low ICC (≤80 μA) | Reduces system standby power in always-connected I/O expanders or sensor hub buffer stages |
| Controlled edge rates | Minimizes overshoot/undershoot on PCB traces - eliminates need for series termination in short-run backplane links |
| High noise immunity | VIH/VIL thresholds scale with VCC (e.g., 3.15 V/1.35 V at 4.5 V) - ensures robust operation under supply ripple or crosstalk |
Applications
| Industrial Backplane Interface | Embedded I/O Expansion |
|---|---|
|
Use Scenario: Isolating and translating signals between a 3.3 V ARM-based main controller and legacy 5 V industrial I/O modules over a 10 cm PCB trace. IC Role / Device Role / Timing Role: Bidirectional bus transceiver managing A↔B data flow with DIR-controlled direction and OE-gated isolation during fault conditions. Use Value: Eliminates need for discrete level shifters while providing 3-state bus arbitration and <12 ns propagation delay for deterministic cycle timing. |
Use Scenario: Expanding GPIO count on a space-constrained medical wearable using a 3.3 V SoC connected to external sensors and indicators operating at 5 V. IC Role / Device Role / Timing Role: Octal transceiver buffering and voltage-adapting parallel sensor data lines, with OE used for power-gating unused channels. Use Value: Reduces BOM count by replacing eight individual level shifters; 80 μA ICC extends battery life in low-duty-cycle monitoring modes. |
| PCB-Level Bus Arbitration | Legacy System Interfacing |
|
Use Scenario: Sharing a single 8-bit data bus among multiple microcontrollers in a modular test equipment chassis via time-sliced access. IC Role / Device Role / Timing Role: Directionally configurable transceiver enabling master-slave handshaking, with OE synchronized to bus grant signals. Use Value: Provides hardware-enforced bus isolation during transitions - prevents contention-induced current spikes exceeding 35 mA per output limit. |
Use Scenario: Connecting a modern FPGA development board (3.3 V I/O) to vintage 5 V parallel port peripherals such as printers or EEPROM programmers. IC Role / Device Role / Timing Role: Voltage-tolerant bidirectional bridge translating logic levels and driving LSTTL loads without external drivers. Use Value: Supports full 8-bit parallel throughput at >10 MHz with guaranteed VOL ≤ 0.26 V and VOH ≥ 3.7 V at 4.5 V supply. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar octal bus transceiver applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SN74LVC245A | Lower VCC range (1.65–3.6 V); faster tpd (6.3 ns @ 3.3 V); higher drive (±24 mA) | Optimized for 3.3 V-only systems; not suitable for 5 V bus interfacing | Select when interfacing only with LVCMOS devices and speed >12 ns is required |
| 74ACT245 | Higher drive (±24 mA); TTL-compatible inputs; VCC = 4.5–5.5 V only; higher ICC (4 mA) | Designed for 5 V TTL-to-CMOS bridging; incompatible with 3.3 V logic | Select for legacy 5 V systems requiring stronger drive and TTL input thresholds |
Compared with SN74LVC245A and 74ACT245, the SN74HC245DBRG4 uniquely balances 2–6 V operation, moderate speed, low power, and LSTTL load compatibility - making it the preferred choice for mixed-voltage, cost-sensitive, and thermally constrained industrial interfaces where wide supply tolerance outweighs raw speed or drive strength.
Availability
SN74HC245DBRG4 is available at Aetrix Electronics and suitable for industrial backplane interfaces, embedded I/O expansion, PCB-level bus arbitration, and legacy system interfacing requiring stable component supply across long production lifecycles.
Supply support for SN74HC245DBRG4 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 connectivity technologies, with decades of experience in logic IC design and industrial-grade qualification.
The SN74HC245DBRG4 belongs to TI's HC (High-Speed CMOS) logic family, engineered for reliable, low-power, mixed-voltage digital interfacing in industrial, computing, and communications equipment.
FAQ
What is the function of the DIR pin on the SN74HC245DBRG4?
The DIR (direction) pin on the SN74HC245DBRG4 controls data flow direction between the A and B buses: when DIR is low, data passes from B to A; when DIR is high, data passes from A to B. This logic-level control operates asynchronously with no clock required, enabling real-time bus reversal in protocols like shared-memory arbitration or dual-processor communication. The SN74HC245DBRG4 does not latch data - it acts as a transparent bidirectional switch governed solely by DIR and OE states.
Can the SN74HC245DBRG4 operate at 3.3 V and interface with 5 V logic?
Yes, the SN74HC245DBRG4 operates across 2 V to 6 V, so it functions reliably at 3.3 V supply while safely accepting and driving 5 V-tolerant signals on both A and B ports. Its VIH threshold at 3.3 V is 2.31 V (70% of VCC), ensuring compatibility with 5 V outputs; its VOH at 3.3 V reaches ≥3.17 V, meeting minimum VIH requirements of standard 5 V TTL and CMOS inputs. This makes the SN74HC245DBRG4 ideal for bridging 3.3 V controllers to 5 V peripherals without external level shifters.
How does the OE pin affect the outputs of the SN74HC245DBRG4?
The OE (output enable) pin on the SN74HC245DBRG4 is active-low: when OE is low, the transceiver operates normally with data flowing according to DIR; when OE is high, all A and B outputs enter high-impedance (3-state) mode, effectively isolating both buses. This allows safe bus sharing in multi-master systems and prevents contention during power-up/down sequences. To ensure defined high-Z state at power-on, TI recommends tying OE to VCC via a pullup resistor - the SN74HC245DBRG4's ≤1 μA input current permits use of high-value resistors (e.g., 100 kΩ) without excessive power loss.
What is the maximum capacitive load the SN74HC245DBRG4 can drive reliably?
The SN74HC245DBRG4 is characterized for switching performance with CL = 50 pF and CL = 150 pF loads. At 50 pF, typical propagation delay is 12 ns (6 V); at 150 pF, it increases to 15 ns. While not explicitly rated beyond 150 pF, the device's ±6 mA drive capability and controlled edge rates allow stable operation into ~200 pF with minor timing degradation - provided trace impedance and routing minimize reflections. For heavier loads, parallel outputs may be used, but total output current must remain ≤75 mA and per-output current ≤25 mA to avoid exceeding absolute maximum ratings.
Is the SN74HC245DBRG4 pin-compatible with other packages in the SN74HC245 family?
Yes, the SN74HC245DBRG4 shares identical pinout and functionality with all 20-pin variants of the SN74HC245, including DW (SOIC), N (PDIP), NS (SOP), and PW (TSSOP) packages. All variants use the same pin numbering and signal mapping shown in Figure 5-1 of the datasheet. This allows drop-in replacement across form factors - for example, substituting the SSOP SN74HC245DBRG4 for the SOIC SN74HC245DWR in existing layouts - provided PCB footprint and thermal constraints are verified for the target package.
SN74HC245DBRG4 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- 74HC
- Package/Case:
- 20-SSOP (0.209", 5.30mm Width)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Discontinued at Digi-Key
- Logic Type:
- Transceiver, Non-Inverting
- Number of Elements:
- 1
- Number of Bits per Element:
- 8
- Input Type:
- -
- Output Type:
- 3-State
- Current - Output High, Low:
- 7.8mA, 7.8mA
- Voltage - Supply:
- 2V ~ 6V
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 20-SSOP
SN74HC245DBRG4 FAQ
1.How can I place an order for SN74HC245DBRG4 through Aetrix?
Please submit a Request for Quotation (RFQ) for SN74HC245DBRG4 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 SN74HC245DBRG4 reliable?
The price and inventory of SN74HC245DBRG4 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SN74HC245DBRG4 is usually 5 days.
3.What payment methods are accepted for SN74HC245DBRG4?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SN74HC245DBRG4 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SN74HC245DBRG4?
SN74HC245DBRG4 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SN74HC245DBRG4 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 SN74HC245DBRG4?
For technical support, including SN74HC245DBRG4 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SN74HC245DBRG4 requirements.
6.How does Aetrix verify that SN74HC245DBRG4 is sourced from the original manufacturer or authorized distributors?
All SN74HC245DBRG4 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 SN74HC245DBRG4 meets industry standards.
7.What is the process for return or replacement of SN74HC245DBRG4?
All SN74HC245DBRG4 units undergo pre-shipment inspection (PSI). If there is an issue with SN74HC245DBRG4, 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 SN74HC245DBRG4 part is unused and in its original packaging.
Return procedure for SN74HC245DBRG4:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SN74HC245DBRG4 Tags
-
SN74LVC1G17DBVR
Texas Instruments
-
SN74LVC1G07DCKR
Texas Instruments
-
SN74LVC1G17DCKR
Texas Instruments
-
SN74LVC1G07DBVR
Texas Instruments
-
SN74LVC1G125DCKR
Texas Instruments
-
SN74AHCT1G126DBVR
Texas Instruments
-
SN74LVC1G125DBVR
Texas Instruments
-
SN74AHCT1G125DBVR
Texas Instruments
-
SN74LVC2G17DBVR
Texas Instruments
-
SN74LVC2G07DCKR
Texas Instruments
-
SN74LVC1G34DCKR
Texas Instruments
-
SN74LVC2G17DCKR
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…
