My Inquiry
My Account
Texas Instruments 74CBT1G125DBVRE4
- Part No.:
- 74CBT1G125DBVRE4
- Manufacturer:
- Texas Instruments
- Category:
- Signal Switches, Multiplexers, Decoders
- Package:
- SC-74A, SOT-753
- Datasheet:
-
74CBT1G125DBVRE4.pdf
- Description:
- IC BUS SWITCH 1 X 1:1 SOT23-5
- Quantity:
- Payment:
- Shipping:
Inventory:3,448
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
74CBT1G125DBVRE4 from Texas Instruments is a single-channel FET bus switch used for high-speed digital signal isolation and bidirectional data routing in 3.3-V/5-V logic systems. It features 5-Ω on-state resistance, TTL-compatible OE control input, and supports ±128 mA continuous channel current. It operates across –40°C to 85°C and is commonly deployed in I²C bus buffering and hot-swap interface isolation.
For engineers reviewing the 74CBT1G125DBVRE4 datasheet, 74CBT1G125DBVRE4 pinout, 74CBT1G125DBVRE4 application, or 74CBT1G125DBVRE4 equivalent, key selection criteria include on-resistance matching, OE logic polarity, thermal performance in SOT-23 packages, and compatibility with 50-pF load switching timing requirements.
Technical Context
This device implements a single NMOS transmission gate architecture with no internal level-shifting circuitry, enabling true bidirectional signal flow between A and B ports when OE is low. Its control logic uses standard TTL voltage thresholds (VIL ≤ 0.8 V, VIH ≥ 2 V) and draws only 1 µA ICC at 5.5 V.
The switch exhibits fast enable/disable timing (ten = 4.9 ns, tdis = 4.2 ns at VCC = 5 V) and propagation delay (tpd = 0.25 ns) due to low on-resistance and minimal parasitic capacitance (Cio(OFF) = 4 pF). ESD protection meets JESD22-A114 (2000-V HBM) and JESD22-A115 (200-V MM).
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| On-state resistance (ron) | 5 Ω typical at VCC = 4.5 V, II = 30 mA - ensures minimal voltage drop and signal integrity for 3.3-V/5-V digital signals. |
| Supply voltage range (VCC) | 4 V to 5.5 V - compatible with standard 5-V TTL and mixed-voltage 3.3-V system interfaces. |
| Control input logic | TTL-compatible (VIH ≥ 2 V, VIL ≤ 0.8 V) - directly driven by legacy 5-V microcontrollers and logic families without level shifters. |
| Switching speed (tpd) | 0.25 ns at VCC = 5 V, CL = 50 pF - supports high-frequency data paths up to ~1 GHz bandwidth under light capacitive loads. |
| ESD rating (HBM) | 2000 V per JESD22-A114-A - provides robust handling margin during board assembly and field operation. |
| Operating temperature | –40°C to +85°C - qualified for industrial-grade embedded control and communications equipment. |
| Package thermal impedance (θJA) | 206°C/W for DBV package - enables sustained 128 mA conduction with <10°C junction rise at ambient 70°C. |
Pinout & Package
SOT-23 (DBV) 5-pin plastic package, 1.45 mm max height, 2.9 mm × 1.6 mm footprint, lead-free NiPdAu finish, MSL Level-1.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (OE) | Output-enable control input | Active-low TTL-compatible signal; drives switch ON when low (≤0.8 V), OFF when high (≥2 V). |
| 2 (A) | Input/output port A | Bidirectional signal terminal; electrically identical to B port; connects directly to source/load without directionality. |
| 3 (GND) | Ground reference | Power return path for internal FET bias and signal reference; must be low-impedance for noise immunity. |
| 4 (VCC) | Positive supply | Provides operating voltage for internal FET gate drive; decoupling capacitor required within 1 cm of pin. |
| 5 (B) | Input/output port B | Bidirectional signal terminal; mirror of A port; forms low-resistance conductive path with A when OE is active low. |
Key Features
| Feature | Design Value |
|---|---|
| Bidirectional signal routing | True analog switch behavior with no internal direction control - preserves signal polarity and timing symmetry between A and B. |
| Low on-resistance drift | ron remains stable across VCC (4–5.5 V) and temperature (–40°C to 85°C), minimizing insertion loss variation in precision data paths. |
| Fast enable/disable transition | ten = 4.9 ns and tdis = 4.2 ns at 5 V - enables precise timing control for burst-mode or clock-gated bus applications. |
| Latch-up immunity | Exceeds 250 mA per JESD17 - prevents destructive latch-up during transient overvoltage or hot-insertion events. |
| Minimal off-state leakage | II = ±1 µA max - avoids signal coupling or DC loading in high-impedance standby states. |
Applications
| I²C Bus Isolation | Hot-Swap Interface Protection |
|---|---|
Use Scenario: Isolating I²C master and slave segments to prevent bus contention during partial system power-up or firmware update. IC Role / Device Role / Timing Role: Bidirectional pass-through switch placed between SDA/SCL lines; enabled only after both sides are powered and stable. Use Value: Prevents back-powering of unpowered devices and eliminates cross-talk during hot-plug events while maintaining sub-1-ns signal fidelity. | Use Scenario: Protecting downstream peripherals from voltage transients during live insertion of expansion cards or modules. IC Role / Device Role / Timing Role: Signal gate inserted between host controller and peripheral interface; disabled during insertion until power and reset sequencing completes. Use Value: Eliminates glitch propagation and ground bounce during hot-swap transitions, supporting JEDEC-compliant insertion protocols. |
| Logic-Level Translation Aid | Test Access Port Multiplexing |
Use Scenario: Enabling interoperability between 3.3-V and 5-V logic domains where full level-shifter ICs are overkill. IC Role / Device Role / Timing Role: Passive switch placed between voltage domains; relies on external pull-ups at appropriate VCC levels on each side. Use Value: Provides low-latency, low-cost bridging without added propagation delay or power consumption of active translators. | Use Scenario: Sharing JTAG or SWD debug pins among multiple MCUs on a shared test access port. IC Role / Device Role / Timing Role: Selectively connecting one MCU's TCK/TMS/TDI/TDO to the common test header under software control via OE. Use Value: Enables deterministic debug access without physical rework or manual jumpering; maintains signal integrity up to 50 MHz. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar FET bus switch applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SN74CBT1G125DBVR | Identical electrical specs and pinout; differs only in tape-and-reel packaging (3000 pcs vs. 3000 pcs) and RoHS marking variant (NIPDAU vs. NIPDAU/SN). | No functional difference; suitable for same PCB layout and design-in; preferred for TI-standard distribution channels. | Select SN74CBT1G125DBVR if sourcing through authorized TI distributors requiring standard part-number suffixes. |
| 74LVC1G3157GW,125 | Higher on-resistance (10 Ω typ), wider VCC range (1.65–5.5 V), CMOS-compatible control (VIH = 70% VCC), smaller SC-70-6 package. | Better for ultra-low-voltage (1.8-V) systems but slower switching (tpd = 3.5 ns); not TTL-compatible. | Choose 74LVC1G3157GW,125 only when operating below 3 V or requiring wider supply flexibility; not drop-in for 5-V TTL control. |
Compared with 74CBT1G125DBVRE4, SN74CBT1G125DBVR offers identical performance and layout compatibility, while 74LVC1G3157GW,125 trades speed and TTL compatibility for broader voltage support and lower static power-making it unsuitable for legacy 5-V control environments but viable in modern mixed-supply designs.
Availability
74CBT1G125DBVRE4 is available at Aetrix Electronics and suitable for industrial automation interfaces, embedded communication buses, and test equipment signal routing requiring stable component supply and long-term manufacturability.
Supply support for 74CBT1G125DBVRE4 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 over 50 years of innovation in high-reliability logic and interface solutions.
The CBT (CrossBar Technology) family, including the 74CBT1G125DBVRE4, was engineered for high-speed, low-distortion digital signal switching in industrial and telecom infrastructure where timing precision and signal integrity are critical.
FAQ
What is the maximum continuous current rating for the 74CBT1G125DBVRE4?
The 74CBT1G125DBVRE4 supports a continuous channel current of 128 mA, verified per absolute maximum ratings in the official Texas Instruments datasheet SCDS046G. This rating applies across the full operating temperature range (–40°C to +85°C) and ensures reliable conduction without thermal runaway when proper PCB copper area and airflow are maintained. Exceeding this current may degrade on-resistance stability or trigger thermal shutdown in adjacent components.
Does the 74CBT1G125DBVRE4 support bidirectional signal flow?
Yes, the 74CBT1G125DBVRE4 supports true bidirectional signal flow between its A and B ports. As a single NMOS transmission gate with no internal direction logic, it passes signals identically in either direction when OE is low. This behavior is confirmed in the function table and logic diagram of the SCDS046G datasheet, making it ideal for I²C, SMBus, and other bidirectional bus applications.
Can the 74CBT1G125DBVRE4 operate with a 3.3-V supply?
No-the 74CBT1G125DBVRE4 requires a minimum VCC of 4 V per recommended operating conditions in SCDS046G. While absolute maximum ratings allow down to –0.5 V, functional operation below 4 V is not guaranteed. For 3.3-V systems, consider alternatives like the SN74LVC1G3157 or SN74AUC1G66, which are explicitly characterized at 3.3 V and below.
What is the thermal resistance (θJA) of the 74CBT1G125DBVRE4 in its SOT-23 package?
The 74CBT1G125DBVRE4 in the SOT-23 (DBV) package has a junction-to-ambient thermal resistance (θJA) of 206°C/W, as specified in the "Absolute Maximum Ratings" section of SCDS046G. This value assumes standard JEDEC 2-layer board conditions and confirms suitability for continuous 128 mA operation with ≤10°C junction-to-ambient rise at 70°C ambient-provided adequate PCB copper pour is used beneath the exposed pad area.
Is the 74CBT1G125DBVRE4 pin-compatible with other members of the SN74CBT1Gxxx family?
Yes-the 74CBT1G125DBVRE4 shares identical pinout (OE, A, GND, VCC, B) and SOT-23 (DBV) package with other single-channel CBT switches such as SN74CBT1G32, SN74CBT1G126, and SN74CBT1G08. However, logic functions differ: 74CBT1G125DBVRE4 is an OE-controlled switch, while others implement gates or inverters. Electrical characteristics (e.g., on-resistance, timing) also vary by part number and must be verified individually.
74CBT1G125DBVRE4 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- 74CBT
- Package/Case:
- SC-74A, SOT-753
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Discontinued at Digi-Key
- Type:
- Bus Switch
- Circuit:
- 1 x 1:1
- Independent Circuits:
- 1
- Current - Output High, Low:
- -
- Voltage Supply Source:
- Single Supply
- Voltage - Supply:
- 4V ~ 5.5V
- Operating Temperature:
- -40°C ~ 85°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23-5
74CBT1G125DBVRE4 FAQ
1.How can I place an order for 74CBT1G125DBVRE4 through Aetrix?
Please submit a Request for Quotation (RFQ) for 74CBT1G125DBVRE4 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 74CBT1G125DBVRE4 reliable?
The price and inventory of 74CBT1G125DBVRE4 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 74CBT1G125DBVRE4 is usually 5 days.
3.What payment methods are accepted for 74CBT1G125DBVRE4?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 74CBT1G125DBVRE4 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 74CBT1G125DBVRE4?
74CBT1G125DBVRE4 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 74CBT1G125DBVRE4 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 74CBT1G125DBVRE4?
For technical support, including 74CBT1G125DBVRE4 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 74CBT1G125DBVRE4 requirements.
6.How does Aetrix verify that 74CBT1G125DBVRE4 is sourced from the original manufacturer or authorized distributors?
All 74CBT1G125DBVRE4 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 74CBT1G125DBVRE4 meets industry standards.
7.What is the process for return or replacement of 74CBT1G125DBVRE4?
All 74CBT1G125DBVRE4 units undergo pre-shipment inspection (PSI). If there is an issue with 74CBT1G125DBVRE4, 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 74CBT1G125DBVRE4 part is unused and in its original packaging.
Return procedure for 74CBT1G125DBVRE4:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
74CBT1G125DBVRE4 Tags
-
SN74HC138DR
Texas Instruments
-
TC7SB3157CFU,LF(CT
Toshiba Semiconductor and Storage
-
74CBTLV3257PW,118
Nexperia USA Inc.
-
SN74CBTLV3257PWR
Texas Instruments
-
74CBTLV3257GUX
Nexperia USA Inc.
-
74HC154BQ,118
Nexperia USA Inc.
-
P3S0200GMX
NXP USA Inc.
-
SN74CB3Q3245PWR
Texas Instruments
-
SN74CB3Q3257RGYR
Texas Instruments
-
TCA9543APWR
Texas Instruments
-
TCA9546APWR
Texas Instruments
-
SN74HC138N
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…
