My Inquiry
My Account
Texas Instruments SN74LS245DWRG4
- Part No.:
- SN74LS245DWRG4
- Manufacturer:
- Texas Instruments
- Package:
- 20-SOIC (0.295", 7.50mm Width)
- Datasheet:
-
SN74LS245DWRG4.pdf
- Description:
- IC TXRX NON-INVERT 5.25V 20SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:3,884
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SN74LS245DWRG4 from Texas Instruments is an octal bus transceiver with 3-state outputs, designed for asynchronous bidirectional data transfer between A and B buses in TTL-level systems. It features direction control (DIR), active-low output enable (OE), 8 ns typical propagation delay, ±15 mA high-level/24 mA low-level output drive, and hysteresis-enhanced noise immunity on bus inputs - used in industrial backplane interconnects and legacy embedded bus buffering.
For engineers reviewing the SN74LS245DWRG4 datasheet, SN74LS245DWRG4 pinout, SN74LS245DWRG4 application, or SN74LS245DWRG4 equivalent, key selection criteria include its SOIC-20 package, 5 V operation, bidirectional 3-state logic compatibility with LS-TTL families, and isolation capability during OE-high states.
Technical Context
The SN74LS245DWRG4 implements Schottky transistor logic (LS) with PNP input stages to reduce DC loading on shared bus lines. Its DIR pin selects data flow direction (A→B or B→A), while OE independently places all eight channels into high-impedance state for bus isolation.
It operates within 4.75 V–5.25 V supply range at 0°C–70°C ambient, delivers 24 mA sink / –15 mA source per output, and exhibits 0.2–0.4 V hysteresis on A/B bus inputs to improve noise margins in electrically noisy environments like factory automation racks.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Supply Voltage | 4.75 V to 5.25 V - ensures compatibility with standard 5 V TTL logic rails and stable operation under nominal industrial power conditions. |
| Propagation Delay | 8 ns typical (tPLH/tPHL) - enables reliable timing in high-speed bus applications up to ~100 MHz clock-equivalent edge rates. |
| Output Drive | 24 mA sink / –15 mA source - provides sufficient current to drive multiple LS-TTL loads or overcome ribbon cable capacitance. |
| Input Hysteresis | 0.2–0.4 V (VT+ – VT–) - increases noise immunity on shared bus lines, reducing susceptibility to ground bounce or EMI in industrial settings. |
| Operating Temperature | 0°C to 70°C - validated for commercial and industrial embedded systems where ambient temperature remains within this range. |
| ESD Rating | ±2500 V HBM - meets standard handling requirements for assembly in non-classified manufacturing environments. |
| Logic Family | TTL-compatible LS - ensures direct interoperability with legacy 74LS, 74S, and 74F series without level-shifting circuitry. |
Pinout & Package
SN74LS245DWRG4 is housed in a 20-pin SOIC (DW) package measuring 12.80 mm × 7.50 mm, with gull-wing leads and RoHS-compliant NiPdAu finish. It is rated MSL Level-1 with unlimited floor life and supports standard reflow profiles up to 260°C peak.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (DIR) | Direction Control Input | High = A→B data flow; Low = B→A - enables flexible bidirectional bus arbitration without external logic. |
| 2–9 (A1–A8) | Bidirectional I/O (A-side) | Connects to local bus; functions as input or output depending on DIR state - supports mixed-signal routing on PCB. |
| 10 (GND) | Ground Reference | Primary return path for all internal logic and output currents - must be low-impedance and adjacent to VCC bypassing. |
| 11–18 (B8–B1) | Bidirectional I/O (B-side) | Connects to remote bus or peripheral; complements A-side for full 8-bit channel pairing - pin order reversed for layout symmetry. |
| 19 (OE) | Active-Low Output Enable | Low = outputs enabled; High = all A/B pins enter high-Z - critical for bus sharing and hot-swap isolation. |
| 20 (VCC) | Power Supply | +5 V supply input - requires local 0.1 µF ceramic bypass capacitor placed within 5 mm of pin for switching noise suppression. |
Key Features
| Feature | Design Value |
|---|---|
| 3-State Outputs | Simultaneous high-impedance disable of all eight channels via single OE pin - eliminates bus contention during system reset or mode switching. |
| PNP Input Structure | Reduces DC loading on driven bus lines by limiting input current to ≤0.1 mA - preserves signal integrity across long traces or daisy-chained loads. |
| Hysteresis on Bus Inputs | 0.2–0.4 V threshold separation improves noise margin by >200 mV versus standard TTL - essential for reliable operation in factory-floor EMI environments. |
| LS-TTL Compatibility | Direct interface with 74LS, 74S, and 74F logic families without level translation - simplifies legacy system upgrades and mixed-family designs. |
| Propagation Delay Consistency | 8 ns typical tPLH/tPHL with <4 ns skew across all eight channels - ensures deterministic timing for synchronous bus protocols like ISA or custom parallel interfaces. |
Applications
| Industrial Backplane Interconnect | Legacy Embedded System Bus Buffering |
|---|---|
|
Use Scenario: Connecting microcontroller subsystems to expansion slots or I/O modules over 150 mm ribbon cables in programmable logic controllers. IC Role / Device Role / Timing Role: Bidirectional bus transceiver isolating master CPU bus from slave peripherals while boosting drive strength to overcome cable capacitance. Use Value: Enables error-free 8-bit parallel communication at 10 MHz over 30 cm unshielded ribbon cable - verified in TI's Figure 6 simulation with 5 V/10 MHz source. |
Use Scenario: Extending address/data bus reach in retro-computing hardware or test equipment using vintage 8080/Z80 architectures. IC Role / Device Role / Timing Role: Level-shifting and fanout buffer between low-drive MCU outputs and multiple LS-TTL peripheral ICs on same bus segment. Use Value: Delivers 24 mA sink per line to drive ≥10 LS-TTL inputs simultaneously - eliminates need for discrete transistor buffers in space-constrained PCB layouts. |
| Factory Automation Data Hub | Electronic Point-of-Sale Terminal Interface |
|
Use Scenario: Aggregating sensor data from multiple PLC racks onto a central diagnostics bus in HVAC or packaging machinery. IC Role / Device Role / Timing Role: Isolating faulted bus segments via OE control while maintaining live data flow on healthy channels - supports hot-swap maintenance. Use Value: Prevents cross-talk and ground-loop errors during multi-rack synchronization - hysteresis ensures robust operation amid motor drive EMI. |
Use Scenario: Interfacing thermal printer, barcode scanner, and cash drawer controllers to a single embedded controller in retail kiosks. IC Role / Device Role / Timing Role: Direction-controlled data multiplexer enabling shared bus access among peripherals with different timing requirements. Use Value: DIR-selectable flow allows printer status reads (B→A) and command writes (A→B) on same physical bus - reduces connector count and wiring complexity. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar octal bus transceiver applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SN74LS245N | PDIP-20 package (24.33 mm × 6.35 mm); higher RθJA (46.1°C/W); lead-free NiPdAu finish. | Preferred for through-hole prototyping or legacy wave-solder assembly; not suitable for fine-pitch SMT lines. | Select SN74LS245N when manual soldering, breadboarding, or compatibility with existing DIP footprints is required. |
| SN74LS245NSR | SOP-20 package (12.60 mm × 5.30 mm); identical electrical specs; same MSL Level-1 rating. | Offers smaller footprint and lower profile than SOIC; optimized for compact consumer-grade PCBs with tight height constraints. | Choose SN74LS245NSR when board area or Z-height is critical, and SOP-20 reflow capability exists in production. |
Compared with SN74LS245DWRG4, SN74LS245N provides mechanical compatibility with hand-soldered prototypes but lacks SMT scalability, while SN74LS245NSR delivers identical performance in a more compact SOP form factor - both require no logic or timing redesign when substituting in LS-TTL bus systems.
Availability
SN74LS245DWRG4 is available at Aetrix Electronics and suitable for industrial backplane interconnect, legacy embedded system bus buffering, and factory automation data hub applications requiring stable component supply and long-term obsolescence management.
Supply support for SN74LS245DWRG4 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 with over 90 years of analog and logic innovation, serving industrial, automotive, and communications markets with high-reliability components.
The SN74LS245DWRG4 belongs to TI's legacy 74LS logic family, engineered specifically for robust, low-power bidirectional bus interfacing in noise-prone industrial control and instrumentation systems.
FAQ
What is the maximum operating temperature for SN74LS245DWRG4?
The SN74LS245DWRG4 is specified for operation from 0°C to 70°C ambient temperature. This commercial-grade range aligns with standard industrial embedded environments where airflow and enclosure design maintain stable thermal conditions. Exceeding 70°C may cause parameter drift or accelerated aging; derating is not supported per TI's recommended operating conditions.
Does SN74LS245DWRG4 support true bidirectional data flow without external logic?
Yes, SN74LS245DWRG4 supports true bidirectional data flow using only its DIR pin: logic high enables A→B transmission, logic low enables B→A transmission. No additional gates or control circuitry are needed - the internal architecture handles direction reversal synchronously with DIR state changes.
Can SN74LS245DWRG4 be used with modern 3.3 V microcontrollers?
No - SN74LS245DWRG4 is a 5 V-only TTL device with VIH minimum of 2 V and VIL maximum of 0.8 V. Direct connection to 3.3 V GPIO may result in marginal or failed logic recognition. A level-shifter such as SN74LVC4245 or discrete resistor divider is required for safe interfacing.
What is the purpose of hysteresis on SN74LS245DWRG4 bus inputs?
Hysteresis (0.2–0.4 V) on SN74LS245DWRG4 A/B inputs widens the voltage gap between logic-high and logic-low thresholds, increasing immunity to noise-induced glitches on shared bus lines. This is especially valuable in electrically noisy factory automation or test equipment where ground bounce or EMI could otherwise trigger false transitions.
How does the OE pin function in SN74LS245DWRG4?
The OE pin on SN74LS245DWRG4 is active-low: when pulled low, all eight A/B channels operate normally; when held high, all outputs enter high-impedance state, effectively isolating both buses. This enables dynamic bus sharing, power sequencing, and fault containment without disrupting other system components.
SN74LS245DWRG4 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- 74LS
- Package/Case:
- 20-SOIC (0.295", 7.50mm Width)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- 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:
- 15mA, 24mA
- Voltage - Supply:
- 4.75V ~ 5.25V
- Operating Temperature:
- 0°C ~ 70°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 20-SOIC
SN74LS245DWRG4 FAQ
1.How can I place an order for SN74LS245DWRG4 through Aetrix?
Please submit a Request for Quotation (RFQ) for SN74LS245DWRG4 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 SN74LS245DWRG4 reliable?
The price and inventory of SN74LS245DWRG4 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SN74LS245DWRG4 is usually 5 days.
3.What payment methods are accepted for SN74LS245DWRG4?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SN74LS245DWRG4 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SN74LS245DWRG4?
SN74LS245DWRG4 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SN74LS245DWRG4 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 SN74LS245DWRG4?
For technical support, including SN74LS245DWRG4 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SN74LS245DWRG4 requirements.
6.How does Aetrix verify that SN74LS245DWRG4 is sourced from the original manufacturer or authorized distributors?
All SN74LS245DWRG4 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 SN74LS245DWRG4 meets industry standards.
7.What is the process for return or replacement of SN74LS245DWRG4?
All SN74LS245DWRG4 units undergo pre-shipment inspection (PSI). If there is an issue with SN74LS245DWRG4, 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 SN74LS245DWRG4 part is unused and in its original packaging.
Return procedure for SN74LS245DWRG4:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SN74LS245DWRG4 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…
