SN74HC245DWR - 8-Bit 3-State Bus Transceiver | Texas Instruments
Référence : SN74HC245DWR ✓ Actif| Qté | Prix unitaire | Total |
|---|---|---|
| 1 | $0.78 | $0,78 |
| 10 | $0.67 | $6,70 |
| 100 | $0.46 | $46,00 |
| 500 | $0.32 | $160,00 |
| 1 000 | $0.24 | $240,00 |
SN74HC245DWR Présentation
A bus transceiver is a logic-interface device that connects two digital buses while allowing each side to drive the other in a controlled sequence. The SN74HC245 belongs to the 74HC CMOS logic family, combining low-power CMOS operation with TTL-compatible high-current outputs. Its eight parallel channels are useful for processor, peripheral, memory, and industrial-control data paths where a shared bidirectional bus must avoid contention.
Key features include a 2 V to 6 V operating supply range, 8-bit parallel operation, 3-state output control, and propagation-delay performance specified for bus-oriented digital systems. The device is designed for asynchronous two-way communication, and its control implementation minimizes external timing requirements. The non-inverting architecture preserves the logical state of each data bit while transferring it in either direction.
The SN74HC245DWR is useful when several devices share a bus and only one device should actively drive the line at a time. DIR determines whether data travels from A to B or B to A, and the output-enable control provides a common way to disconnect the transceiver during reset, idle periods, arbitration, or bus multiplexing. Because outputs can be disabled, the device helps prevent driver contention when multiple bus agents share the same conductors.
Typical applications include microprocessor and microcontroller bus isolation, parallel peripheral interfaces, memory-bus fanout, test and measurement equipment, communications equipment, and industrial control systems. Designers should check timing margins, enable sequencing, and input/output loading against the specific bus architecture. For high-speed or long interconnect paths, trace topology, capacitance, and signal-integrity margin should be evaluated rather than relying only on the nominal propagation delay.
This page combines manufacturer specifications, distributor availability references, application guidance, and verified comparison data to support component selection and PCB-compatible replacement decisions.
Alternatives de remplacement direct pour SN74HC245DWR — même boîtier, compatible broche à broche. Les références à boîtier différent nécessitant une retouche du PCB sont exclues.
Outil de comparaison rapide — sélectionnez des références alternatives pour une comparaison côte à côte :
CD74HC245E
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
MC74HC245ADWG
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
SN74HC245DW
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
SN74AHC245DW
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
SN74HC244DW
✅ Remplacement direct ⚠️ Spécifications non vérifiées📋 Alternative de référence (hors catalogue)
SN74HC245DWR Valeurs maximales et caractéristiques électriques
| Device Type | Octal bus transceiver |
| Number of Elements | 1 element |
| Bits per Element | 8 bits |
| Type de sortie | 3-state, non-inverting |
| Supply Voltage Range | 2 V to 6 V |
| Température de fonctionnement | -40 C to +85 C |
| Boîtier | 20-pin SOIC |
| Type de montage | Surface mount |
| Technology | CMOS |
| Bus Direction Control | DIR input |
| Output Enable Control | Output-enable input |
| Largeur du bus de données | 8 bits |
| High-Current Output Capability | Drive up to 15 LSTTL loads |
| Low Power Consumption | 80 uA maximum ICC |
| Nombre de broches | 20 pins |
| Manufacturer Description | Octal bus transceivers with 3-state outputs |
Configuration des broches de SN74HC245DWR
| Broche 1 | 1A — A-side bus input/output 1 |
| Broche 2 | 1B — B-side bus input/output 1 |
| Broche 3 | 2A — A-side bus input/output 2 |
| Broche 4 | 2B — B-side bus input/output 2 |
| Broche 5 | 3A — A-side bus input/output 3 |
| Broche 6 | 3B — B-side bus input/output 3 |
| Broche 7 | 4A — A-side bus input/output 4 |
| Broche 8 | 4B — B-side bus input/output 4 |
| Broche 9 | OE — Output enable control |
| Broche 10 | DIR — Data-direction control |
| Broche 11 | 5B — B-side bus input/output 5 |
| Broche 12 | 5A — A-side bus input/output 5 |
| Broche 13 | 6B — B-side bus input/output 6 |
| Broche 14 | 6A — A-side bus input/output 6 |
| Broche 15 | 7B — B-side bus input/output 7 |
| Broche 16 | 7A — A-side bus input/output 7 |
| Broche 17 | 8B — B-side bus input/output 8 |
| Broche 18 | 8A — A-side bus input/output 8 |
| Broche 19 | GND — Ground |
| Broche 20 | VCC — Positive supply voltage |
Applications typiques
SN74HC245DWR convient pour 7 applications: Microprocessor Bus Isolation, Peripheral Data Interfaces, Memory-Bus Fanout, Industrial Control Data Paths, Communications and Test Equipment, Embedded Controller Bus, General Digital Signal Interfacing.
Microprocessor Bus Isolation
The SN74HC245DWR is appropriate for a bidirectional processor bus because it provides eight data channels, DIR-based direction control, and a common 3-state output enable. It can isolate a peripheral bus during reset or when another bus master takes ownership, preventing sustained driver contention. The 2 V-to-6 V supply range fits 74HC-compatible systems, while the 20-pin SOIC package supports conventional surface-mount assembly. Designers should confirm propagation delay and bus-loading margins against the processor clock and peripheral timing specifications.
Recommandé
Peripheral Data Interfaces
Use the SN74HC245DWR when a parallel peripheral interface needs a controlled connection to a shared data bus. Eight bits can be transferred in parallel, and DIR lets the controller select the A-to-B or B-to-A direction. The 3-state outputs are useful when the peripheral must be disconnected while another device drives the bus. Check that the enabled outputs meet the peripheral’s input thresholds, that the disabled outputs have acceptable leakage, and that the interface timing includes sufficient setup and hold margin.
Recommandé
Memory-Bus Fanout
The SN74HC245DWR can buffer an eight-bit memory or register bus where multiple logic sections need a controlled connection point. Its non-inverting channels preserve data, while DIR and output-enable controls allow the designer to prevent multiple sections from driving simultaneously. The 20-pin SOIC footprint is practical for conventional PCB routing, and the 2 V-to-6 V operation supports 74HC-family rails. Validate memory access time, bus capacitance, and contention-free sequencing for the specific memory device.
Recommandé
Industrial Control Data Paths
The SN74HC245DWR is suitable for industrial control systems that need an eight-bit bidirectional logic interface within a 2 V-to-6 V environment. The verified operating-temperature range of -40 C to +85 C supports many industrial equipment designs, while the 3-state outputs permit bus sharing and controlled isolation. The final enclosure temperature, grounding strategy, isolation requirements, and ESD protection must be evaluated separately because the supplied data does not specify automotive qualification or system-level protection ratings.
Recommandé
Communications and Test Equipment
In communications and test equipment, an eight-bit bus transceiver can connect control or status lines between modules while allowing one side to disconnect electrically during another side’s active drive period. The SN74HC245DWR’s DIR and output-enable controls help structure bus ownership, and its CMOS 2 V-to-6 V operation aligns with many digital subsystems. For high-speed instruments or long traces, use the manufacturer timing characteristics to assess propagation delay, capacitance loading, crosstalk, and the need for series termination.
Recommandé
Embedded Controller Bus
An embedded controller can use the SN74HC245DWR to place an eight-bit parallel data bus into a high-impedance state when the controller is not the active bus master. This is useful in systems containing multiple address or data sources that must share conductors. The DIR pin should be changed only after the current output enable is inactive, and the controller should retain control of reset and power-up states. Verify the selected microcontroller’s voltage, timing, and output-drive requirements against the transceiver datasheet.
Recommandé
General Digital Signal Interfacing
The SN74HC245DWR can serve as a general-purpose eight-channel interface when two logic domains must exchange non-inverting data over a shared bus. Its 3-state outputs reduce the need for discrete isolation components when bus ownership can be managed by DIR and output-enable logic. The 20-pin SOIC package and -40 C to +85 C specified range make it broadly useful, but the circuit must still account for supply sequencing, signal levels, trace capacitance, and timing margins. The component does not provide level translation between unrelated voltage domains by itself.
Recommandé
Récapitulatif des produits recommandés
Données de référence d'ingénierie pour SN74HC245DWR — comparaison, recommandations de conception et informations de conformité.
Guide de sélection
Comparaison avec les alternatives
| Paramètre | Ce produit | CD74HC245E | MC74HC245ADWG | SN74HC245DW | SN74AHC245DW |
|---|---|---|---|---|---|
| Package | 20-pin SOIC | 20-pin SOIC - same package | 20-pin SOIC - same package | 20-pin SOIC - same package | 20-pin SOIC - same package |
| Brand | Texas Instruments | Texas Instruments | onsemi | Texas Instruments | Texas Instruments |
| Function | 8-bit bidirectional transceiver | 8-bit bidirectional transceiver | Octal bus transceiver | Octal bus transceiver | 8-bit transceiver |
| Output State | 3-state | 3-state | 3-state | 3-state | 3-state |
| Data Width | 8 bits | 8 bits | 8 bits | 8 bits | 8 bits |
| Direction Control | DIR input | DIR input | Direction control | DIR input | Direction control |
Principaux différenciateurs
- True bidirectional eight-bit bus interface (vs SN74HC244DW)
- Cross-brand sourcing path (vs MC74HC245ADWG)
- Broad 74HC voltage compatibility (vs SN74AHC245DW)
Notes de conception
Never change DIR while the transceiver is still enabled and driving. Assert the output-enable control first, allow the required disable interval from the datasheet, change DIR, and then re-enable the new direction. This sequencing prevents two external bus drivers from fighting each other and reduces the risk of excessive current, undefined levels, or data corruption.
Place the 20-pin SOIC close to the supported bus and keep the ground return continuous. Route the eight A-side and eight B-side nets as an orderly parallel group, minimize stubs, and keep DIR and output-enable traces away from sensitive clock or analog lines. Confirm the PCB footprint against the manufacturer package drawing because SOIC land patterns can differ between vendors even when the nominal package is the same.
Check propagation delay, setup and hold time, trace capacitance, and the number of enabled loads against the system timing budget. The verified data confirms an 8-bit, 3-state transceiver but does not provide every timing value in the supplied snippets. For long PCB traces, high fanout, or unusually fast buses, measure edge behavior and consider termination, series damping, or a different logic family rather than assuming the nominal logic delay is sufficient.
Operate the device only within its verified 2 V-to-6 V supply range and connect the VCC and GND pins with low-impedance paths. The supplied data identifies CMOS technology and low power consumption of up to 80 uA ICC, but the actual system power depends on enabled duration, load capacitance, switching activity, and supply voltage. Confirm signal-level compatibility at every enabled and disabled state rather than treating the family-level voltage range as automatic level translation.
Informations de conformité
The supplied verified web data does not explicitly state RoHS, REACH, lead-free, halogen-free, or conflict-minerals status for the exact ordering code. AEC-Q100 is marked not_applicable because the component is a general-purpose logic IC and no automotive qualification is stated.
