My Inquiry
My Account
Texas Instruments SN74CBT3306D
- Part No.:
- SN74CBT3306D
- Manufacturer:
- Texas Instruments
- Category:
- Signal Switches, Multiplexers, Decoders
- Package:
- 8-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
SN74CBT3306D.pdf
- Description:
- IC BUS SWITCH 1 X 1:1 8SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:1,552
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SN74CBT3306D from Texas Instruments is a dual FET bus switch IC with independent 5-Ω on-state resistance switches, TTL-compatible control inputs (VIH = 2 V, VIL = 0.8 V), and operation across −40°C to 85°C. It enables bidirectional signal routing in low-voltage data paths such as address/data buses in microcontroller peripherals and memory interfaces.
For engineers reviewing the SN74CBT3306D datasheet, SN74CBT3306D pinout, SN74CBT3306D application, or SN74CBT3306D equivalent, key selection criteria include on-resistance matching (5–7 Ω), sub-1 ns propagation delay (tpd = 0.25 ns at VCC = 5 V), OE-controlled isolation, and SOIC-8 thermal performance (θJA = 97°C/W).
Technical Context
The SN74CBT3306D implements two independent transmission-gate-based FET switches, each controlled by a dedicated OE input operating in positive logic: OE low enables A↔B conduction; OE high disconnects both ports. No internal level-shifting or biasing circuitry is present - the switch passes signals bi-directionally with minimal voltage drop.
Each channel supports rail-to-rail analog/digital signal switching up to 128 mA continuous current, with input/output voltage range extending from −0.5 V to 7 V. The device draws only 3 μA ICC at VCC = 5.5 V and exhibits low capacitive loading: Ci = 3 pF (control), Cio(OFF) = 4 pF (switch off-state).
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| On-state resistance (ron) | 5–7 Ω typical at VI = 2.4 V, II = 15 mA - ensures minimal signal attenuation and voltage drop in 3.3 V/5 V digital buses. |
| Propagation delay (tpd) | 0.25 ns at VCC = 5 V, CL = 50 pF - enables use in high-speed parallel interfaces up to ~1 GHz effective bandwidth. |
| Supply voltage (VCC) | 4–5.5 V recommended - compatible with standard 5 V TTL and mixed 3.3 V/5 V system backplanes. |
| Control input thresholds | VIH = 2 V, VIL = 0.8 V - guarantees reliable TTL-level compatibility without external level shifters. |
| Off-state capacitance (Cio) | 4 pF at VO = 3 V or 0 V - minimizes crosstalk and loading on adjacent high-impedance nodes during disable. |
| Thermal resistance (θJA) | 97°C/W for SOIC-8 package - defines maximum power dissipation (≤125 mW at ΔT = 12°C rise) under natural convection. |
Pinout & Package
SN74CBT3306D is housed in an 8-pin SOIC (D) package per JEDEC MS-012AA, 3.91 mm body width, 1.75 mm max height, 1.27 mm lead pitch. Pin 1 marked by beveled corner or notch.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (1OE) | Channel 1 output-enable input | Active-low control: drives 1A↔1B path when low; high-impedance isolation when high. |
| 2 (1A) | Channel 1 port A terminal | Bidirectional signal node - connects to upstream source (e.g., MCU address line) with no polarity constraint. |
| 3 (1B) | Channel 1 port B terminal | Bidirectional signal node - connects to downstream load (e.g., memory chip input) with no polarity constraint. |
| 4 (GND) | Ground reference | Return path for all internal FET sources and control logic; must be low-impedance for stable switching. |
| 5 (VCC) | Positive supply | Power rail for internal gate drive and level translation; bypass capacitor required near pin. |
| 6 (2OE) | Channel 2 output-enable input | Independent active-low control for second switch - enables asynchronous enable/disable of dual channels. |
| 7 (2B) | Channel 2 port B terminal | Second bidirectional node - supports separate data path (e.g., I/O expansion bus segment). |
| 8 (2A) | Channel 2 port A terminal | Second bidirectional node - electrically isolated from Channel 1 except via shared VCC/GND. |
Key Features
| Feature | Design Value |
|---|---|
| 5-Ω matched on-resistance | Ensures <10 mV drop at 2 mA, preserving logic margins in 3.3 V systems and reducing timing skew between parallel lines. |
| TTL-compatible OE inputs | Eliminates need for pull-up resistors or level translators when driven directly from 74LS/74HC outputs. |
| Sub-nanosecond propagation delay | Supports clean edge integrity in >500 MHz clock domains without added jitter or duty-cycle distortion. |
| Low off-state capacitance (4 pF) | Maintains signal integrity on stubbed or unterminated traces by minimizing capacitive loading during disable. |
| Rail-to-rail analog/digital switching | Allows use beyond digital buses - e.g., analog sensor multiplexing or audio signal gating without DC blocking. |
Applications
| Memory Address Bus Switching | Microcontroller I/O Expansion |
|---|---|
Use Scenario: Isolating multiple SRAM chips sharing a common address bus on an 8-bit MCU design. IC Role / Device Role / Timing Role: Dual-channel bidirectional bus switch enabling time-multiplexed access to two memory banks without contention. Use Value: Prevents address-line loading and signal reflection using 5 Ω Ron and 4 pF Cio(OFF), maintaining setup/hold timing at 12 MHz bus rates. | Use Scenario: Adding GPIO extension capability to an STM32F103 via SPI-connected I/O expander with shared data lines. IC Role / Device Role / Timing Role: Signal isolator between main MCU and peripheral I/O expander, controlled by dedicated OE pins. Use Value: Enables hot-plug-safe I/O reconfiguration with <0.25 ns tpd, avoiding metastability during dynamic enable transitions. |
| Legacy Peripheral Interface Multiplexing | Test Access Port (TAP) Signal Gating |
Use Scenario: Sharing JTAG/SWD debug lines between two ARM Cortex-M cores on a dual-core PCB layout. IC Role / Device Role / Timing Role: Bidirectional pass-gate for TCK/TMS/TDI/TDO lines, enabled only during active debug session. Use Value: Reduces debug-port crosstalk and EMI with 4 pF off-capacitance while preserving signal edge rate via 5 Ω Ron. | Use Scenario: Gating boundary-scan test signals into FPGA configuration banks during production ICT testing. IC Role / Device Role / Timing Role: Controlled isolation element inserted between test controller and DUT to prevent back-driving. Use Value: Guarantees safe 128 mA channel current handling and −0.5 V to 7 V fault tolerance during test fixture contact bounce. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar bus switch applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SN74CBTD3306D | Higher VCC rating (up to 7 V), lower Ron (3.5 Ω typ), but requires ≥2.3 V VIH - not TTL-compatible. | Preferred in 5 V-only systems needing tighter resistance matching; unsuitable for legacy 74LS-driven controls. | Select SN74CBTD3306D only if VIH > 2.3 V is guaranteed and Ron < 4 Ω is critical. |
| 74LVC1G3157DP | Single-channel, 5-pin SC70 package, Ron = 6 Ω, VIH = 1.7 V - smaller footprint but half the channel count. | Suitable for space-constrained single-line gating (e.g., reset or interrupt lines); not a drop-in replacement for dual-bus routing. | Use 74LVC1G3157DP when board area is limiting and only one switch is needed per location. |
Compared with SN74CBT3306D, SN74CBTD3306D offers better on-resistance and voltage margin but sacrifices TTL compatibility, while 74LVC1G3157DP trades channel count and package size for integration density - neither is pin-compatible, requiring layout revision.
Availability
SN74CBT3306D is available at Aetrix Electronics and suitable for memory interface isolation, microcontroller I/O expansion, legacy peripheral multiplexing, and test access port gating requiring stable component supply and long-term industrial availability.
Supply support for SN74CBT3306D 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 company headquartered in Dallas, Texas, delivering analog, embedded processing, and connectivity solutions since 1930.
The SN74CBT3306D belongs to TI's CBT (CrossBar Technology) family of FET bus switches, designed specifically for low-latency, low-distortion signal routing in mixed-voltage digital systems.
FAQ
What is the maximum continuous current rating per channel of the SN74CBT3306D?
The SN74CBT3306D supports up to 128 mA continuous channel current per switch, verified under absolute maximum ratings. This allows safe operation driving terminated 50 Ω transmission lines or fan-out to multiple CMOS inputs without thermal derating at ambient ≤85°C. Exceeding this current risks permanent damage due to junction overheating.
Does the SN74CBT3306D require external pull-up or pull-down resistors on its OE inputs?
No, the SN74CBT3306D does not require external pull-up or pull-down resistors on its OE inputs. Its TTL-compatible thresholds (VIH = 2 V, VIL = 0.8 V) allow direct connection to standard logic outputs. However, TI recommends tying unused OE inputs to VCC or GND to prevent floating states that may cause undefined switching behavior.
Can the SN74CBT3306D be used to switch analog signals such as audio or sensor outputs?
Yes, the SN74CBT3306D can switch analog signals including audio and sensor outputs because it uses FET transmission gates with rail-to-rail voltage handling (−0.5 V to 7 V) and no internal clamping diodes. Its 5–7 Ω Ron introduces negligible distortion below 100 kHz, and 4 pF Cio(OFF) limits crosstalk - making it suitable for DC-coupled analog multiplexing where bandwidth and linearity requirements are moderate.
What is the thermal resistance (θJA) of the SN74CBT3306D in its SOIC-8 package?
The SN74CBT3306D in the SOIC-8 (D) package has a junction-to-ambient thermal resistance (θJA) of 97°C/W, measured per JESD 51-7. This value assumes standard JEDEC 2-layer board conditions. For sustained 128 mA operation, power dissipation remains below 100 mW, resulting in a junction temperature rise of <10°C above ambient - well within safe operating limits.
Is the SN74CBT3306D pin-compatible with other members of the CBT bus switch family?
No, the SN74CBT3306D is not universally pin-compatible across the CBT family. While it shares the same SOIC-8 pinout with SN74CBT3305D (single-channel variant), it differs from SN74CBT3244D (octal non-inverting buffer) and SN74CBT3245D (octal inverting buffer) in both pin function and count. Always verify pin mapping against the specific device's datasheet before substitution.
SN74CBT3306D Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- 74CBT
- Package/Case:
- 8-SOIC (0.154", 3.90mm Width)
- Packaging:
- Bulk
- Product Status:
- Obsolete
- Type:
- Bus Switch
- Circuit:
- 1 x 1:1
- Independent Circuits:
- 2
- Current - Output High, Low:
- -
- Voltage Supply Source:
- Single Supply
- Voltage - Supply:
- 4.5V ~ 5.5V
- Operating Temperature:
- -40°C ~ 85°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 8-SOIC
SN74CBT3306D FAQ
1.How can I place an order for SN74CBT3306D through Aetrix?
Please submit a Request for Quotation (RFQ) for SN74CBT3306D 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 SN74CBT3306D reliable?
The price and inventory of SN74CBT3306D are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SN74CBT3306D is usually 5 days.
3.What payment methods are accepted for SN74CBT3306D?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SN74CBT3306D transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SN74CBT3306D?
SN74CBT3306D orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SN74CBT3306D 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 SN74CBT3306D?
For technical support, including SN74CBT3306D datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SN74CBT3306D requirements.
6.How does Aetrix verify that SN74CBT3306D is sourced from the original manufacturer or authorized distributors?
All SN74CBT3306D 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 SN74CBT3306D meets industry standards.
7.What is the process for return or replacement of SN74CBT3306D?
All SN74CBT3306D units undergo pre-shipment inspection (PSI). If there is an issue with SN74CBT3306D, 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 SN74CBT3306D part is unused and in its original packaging.
Return procedure for SN74CBT3306D:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SN74CBT3306D 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…
