SN74LVTH245APW - 3.3V ABT Octal Bus Transceiver TSSOP-20 | TI
MPN: SN74LVTH245APW ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.42 | $1.42 |
| 10 | $1.18 | $11.80 |
| 100 | $0.92 | $92.00 |
| 500 | $0.78 | $390.00 |
| 1,000 | $0.69 | $690.00 |
SN74LVTH245APW Overview
A bus transceiver (also known as a bus driver/receiver pair, octal transceiver, or bidirectional buffer) is a digital logic device that converts and bridges signals between two buses while providing 3-state isolation. In the system hierarchy, transceivers sit between microprocessors and peripherals: transceiver -> bus driver -> buffer/driver -> logic IC -> integrated circuit. The bidirectional architecture allows data to flow in either direction on a shared data path, making bus transceivers fundamental building blocks in any system that needs to multiplex or isolate parallel buses.
Key features of the SN74LVTH245APW include support for live insertion through Ioff and power-up 3-state, hot-insertion capability, bus-hold on data inputs (eliminates external pull-up resistors), and typical VOLP (output ground bounce) performance under 0.8V at 25°C with VCC = 3.3V. The device supports unregulated battery operation down to 2.7V, allowing direct connection to single Li-ion cells or other battery sources without a regulated supply.
The SN74LVTH245A family uses TI's ABT (Advanced BiCMOS Technology) process, combining bipolar and CMOS transistors to deliver TTL-compatible voltage thresholds with low static power dissipation. The bus-hold circuitry uses a small active feedback circuit on each I/O pin to retain the last driven logic state, eliminating the need for external pull-up or pull-down resistors on idle or tri-stated lines. The 3-state outputs isolate either bus when disabled, supporting bus multiplexing across multiple sources.
Typical applications include point-to-point asynchronous data transfer between data buses in networking switches, memory modules, and embedded CPU/memory expansion boards. The wide VCC range and TTL input compatibility also suit industrial backplane designs, PCI bus interfaces, and 3.3V/5V mixed-voltage systems. The hot-insertion capability makes it suitable for hot-swappable cards and field-replaceable modules.
Designers should note that the A-port and B-port pins are not 5V tolerant unless VCC is at least 3.0V; for 5V-only legacy buses, a level shifter such as the SN74LVC4245A should be considered. Place VCC decoupling capacitors of 0.1 µF ceramic as close as possible to the device supply pin, with a bulk 10 µF tantalum or ceramic on the same rail.
This page consolidates distributor pricing, drop-in alternatives including both same-brand and cross-brand TSSOP-20 devices, and practical design notes that are not collected in the manufacturer datasheet, giving engineers a single authoritative source for procurement and substitution decisions.
Drop-in alternatives for SN74LVTH245APW — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with SN74LVTH245APW (same form factor and footprint) — differing in Operating Temperature, RoHS Status, Live Insertion Support, Logic Family, Logic Type.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
SN74LVTH245APWR
✅ Drop-In✓ In Stock
$0.34 / Unit
View Datasheet →SN74LVTH245APWT
✅ Drop-In📋 Reference alternative (not in catalog)
SN74LVTH245AIPW
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
SN74LVC245APW
✅ Drop-In📋 Reference alternative (not in catalog)
74LVT245PW
✅ Drop-In📋 Reference alternative (not in catalog)
74LCX245PW
✅ Drop-In📋 Reference alternative (not in catalog)
74LVCH245APW
✅ Drop-In📋 Reference alternative (not in catalog)
SN74LVTH245APW Maximum Ratings & Electrical Characteristics
| Function | Octal Bus Transceiver with 3-State Outputs |
| Number of Elements | 1 |
| Bits per Element | 8 |
| Logic Type | Non-Inverting Transceiver |
| Output Type | 3-State |
| Direction Control Pin | Yes (DIR) |
| Output Enable Pin | Yes (active-low OE) |
| Supply Voltage (VCC) | 2.7 V to 3.6 V |
| Operating Temperature | -40 °C to +85 °C |
| Input Compatibility | TTL-compatible |
| Output Compatibility | LVTTL (3.3V system, interfaces to 5V TTL) |
| Package Type | TSSOP-20 (PW) |
| Pin Count | 20 |
| Mounting Type | Surface Mount |
| Live Insertion Support | Yes (Ioff + power-up 3-state) |
| Bus-Hold Inputs | Yes |
| RoHS Status | Compliant |
SN74LVTH245APW Pin Configuration
| Pin 1 | DIR — Direction control input (HIGH: B=A, LOW: A=B) |
| Pin 2 | A1 — A-bus data I/O, channel 1 |
| Pin 3 | A2 — A-bus data I/O, channel 2 |
| Pin 4 | A3 — A-bus data I/O, channel 3 |
| Pin 5 | A4 — A-bus data I/O, channel 4 |
| Pin 6 | A5 — A-bus data I/O, channel 5 |
| Pin 7 | A6 — A-bus data I/O, channel 6 |
| Pin 8 | A7 — A-bus data I/O, channel 7 |
| Pin 9 | A8 — A-bus data I/O, channel 8 |
| Pin 10 | GND — Ground |
| Pin 11 | B8 — B-bus data I/O, channel 8 |
| Pin 12 | B7 — B-bus data I/O, channel 7 |
| Pin 13 | B6 — B-bus data I/O, channel 6 |
| Pin 14 | B5 — B-bus data I/O, channel 5 |
| Pin 15 | B4 — B-bus data I/O, channel 4 |
| Pin 16 | B3 — B-bus data I/O, channel 3 |
| Pin 17 | B2 — B-bus data I/O, channel 2 |
| Pin 18 | B1 — B-bus data I/O, channel 1 |
| Pin 19 | OE — Output enable, active low (HIGH = high-Z) |
| Pin 20 | VCC — Power supply (2.7 V to 3.6 V) |
Typical Applications
SN74LVTH245APW is suitable for 6 applications: 3.3V Data Bus Multiplexing, Hot-Swappable Card Interface, Memory Module Buffering, Industrial Backplane Bus Driver, PCI / Embedded Bus Expansion, Portable / Battery-Powered Devices.
3.3V Data Bus Multiplexing
The SN74LVTH245APW is purpose-built for 3.3V data bus multiplexing in networking switches, memory modules, and embedded CPU/memory expansion boards. Its eight non-inverting bidirectional channels, controlled by DIR (direction) and active-low OE, allow two buses to share a single data path with full 3-state isolation. The 2.7-3.6V VCC range supports unregulated battery-backed designs, while TTL-compatible I/O cleanly bridges to legacy 5V peripheral chips. Hot-insertion (Ioff + power-up 3-state) makes it suitable for live-backplane and hot-swap card applications where signal integrity during insertion is critical.
Recommended
Hot-Swappable Card Interface
The SN74LVTH245APW's Ioff and power-up 3-state features make it ideal for hot-swappable card interfaces in networking, telecom, and storage systems. When a card is inserted, the Ioff circuitry prevents backflow current through partially-powered I/O pins, protecting both the card and the backplane. Once VCC stabilizes, the bus-hold inputs maintain the last valid logic state until the controller drives DIR/OE. The 64 mA drive capability cleanly drives backplane traces with proper termination, while the TSSOP-20 footprint suits dense mezzanine card designs.
Recommended
Memory Module Buffering
Use the SN74LVTH245APW to buffer address and data lines between a memory controller and DRAM/NOR flash modules in 3.3V embedded systems. Its 4 ns propagation delay at 3.3V adds minimal timing overhead, and the 32-64 mA drive strength easily handles multi-load memory buses. Bus-hold inputs eliminate external pull-up resistors on shared lines, simplifying PCB layout and reducing BOM cost. The device's 2.7V minimum VCC allows direct connection to Li-ion battery rails in portable memory products without an additional regulator.
Recommended
Industrial Backplane Bus Driver
The SN74LVTH245APW operates over the -40 °C to +85 °C industrial temperature range, making it suitable for factory automation backplanes, PLC I/O modules, and industrial Ethernet switch line cards. Its TTL-compatible inputs interface cleanly with legacy 5V PLC logic while the 3.3V core supply integrates with modern processors. Bus-hold on data inputs prevents floating-line faults in noisy industrial environments where long cables and EMI can otherwise drive inputs to intermediate voltages. The TSSOP-20 package supports dense backplane routing.
Recommended
PCI / Embedded Bus Expansion
The SN74LVTH245APW bridges 3.3V embedded CPU buses and 5V peripheral chips in PCI card designs and SoC expansion interfaces. Its TTL-compatible inputs accept 5V signals from legacy peripherals while operating from a 3.3V supply, eliminating the need for a separate level shifter on TTL-level lines. The bidirectional DIR control allows the CPU and peripheral to share a bus in half-duplex fashion. Hot-insertion support protects the backplane during card swap events, and the wide operating voltage range simplifies power tree engineering.
Recommended
Portable / Battery-Powered Devices
In portable and battery-powered designs such as handheld instruments, wearables, and IoT edge devices, the SN74LVTH245APW operates directly from a single Li-ion cell (2.7-3.6V) without a regulated 3.3V rail. The TTL-compatible I/O bridges the device to legacy 5V sensors and peripherals, while the low quiescent current extends battery life. Bus-hold eliminates external pull-up resistors on idle lines, reducing leakage paths. TSSOP-20 packaging suits space-constrained wearable designs where every square millimeter of PCB matters.
Recommended
Recommended Products Summary
Engineering reference data for SN74LVTH245APW — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | SN74LVTH245APWR | SN74LVTH245APWT | SN74LVC245APW | 74LVT245PW | 74LCX245PW |
|---|---|---|---|---|---|---|
| Package | TSSOP-20 (PW) | TSSOP-20 (PW) - same | TSSOP-20 (PW) - same | TSSOP-20 (PW) - same | TSSOP-20 (PW) - same | TSSOP-20 (PW) - same |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | NXP Semiconductors | NXP Semiconductors |
| VCC Range | 2.7 V to 3.6 V | 2.7 V to 3.6 V | 1.65 V to 3.6 V | 2.7 V to 3.6 V | 2.0 V to 3.6 V | |
| Bus-Hold Inputs | Yes | Yes | No | Yes | No | |
| Ioff / Hot-Insertion | Yes | Yes | No | Yes | Yes | |
| Output Drive (typ) | ±64 mA | ±64 mA | ±24 mA | ±64 mA | ±24 mA | |
| Propagation Delay (max) | 4 ns at 3.3 V | 4 ns at 3.3 V | 5 ns at 3.3 V | 4 ns at 3.3 V | 5 ns at 3.3 V | |
| Operating Temperature | -40 °C to +85 °C | -40 °C to +85 °C | -40 °C to +125 °C | -40 °C to +85 °C | -40 °C to +85 °C |
Key Differentiators
- Bus-hold inputs eliminate external pull-up resistors (vs SN74LVC245APW)
- Ioff and power-up 3-state for true hot-insertion (vs SN74LVC245APW)
- Higher output drive for backplane applications (vs SN74LVC245APW)
Design Notes
Place a 0.1 µF X7R ceramic decoupling capacitor as close as possible to the VCC pin (pin 20) of the SN74LVTH245APW, with the loop area kept under 5 mm². Add a bulk 10 µF tantalum or ceramic capacitor on the same 3.3 V rail within 25 mm. The device draws modest supply current (~50 µA quiescent plus load-dependent active current), but hot-plug inrush during VCC ramp can briefly demand higher current; sufficient bulk capacitance prevents backplane droop during insertion events.
Do not assume 5V tolerance on the SN74LVTH245APW inputs - the device's inputs are TTL-compatible but not 5V tolerant when VCC is below 3.0V. For true 5V input tolerance, choose the SN74LVC4245A (dual-supply) or the NXP 74LCX245PW (5V tolerant, VCC-independent). Additionally, the DIR pin must be driven to a valid logic level - never left floating - because floating inputs can cause both buses to drive simultaneously, creating contention. Use a 10 kΩ pull-up to VCC if DIR is driven by an open-drain source.
Route the A-bus and B-bus traces on separate layers or with adequate spacing to minimize crosstalk on the TSSOP-20 footprint. Match trace lengths within each bus to within 25 mm (150 ps skew) for parallel-interface timing budgets above 50 MHz. The TSSOP-20 (PW) thermal pad is not present on this package (only on the RGT/RGW variants), so standard TSSOP land pattern with 0.65 mm pitch is sufficient. Reserve a guard trace around DIR and OE pins if they run parallel to high-frequency switching signals.
Compliance Information
RoHS and REACH compliant per TI product page. Industrial temperature grade (-40 °C to +85 °C); not AEC-Q100 qualified. Halogen-free per TI material declaration.
