My Inquiry
My Account
Texas Instruments SN74CB3Q3245ZQNR
- Part No.:
- SN74CB3Q3245ZQNR
- Manufacturer:
- Texas Instruments
- Category:
- Signal Switches, Multiplexers, Decoders
- Package:
- 20-VFBGA
- Datasheet:
-
SN74CB3Q3245ZQNR.pdf
- Description:
- IC BUS SWITCH 8 X 1:1 20BGA
- Quantity:
- Payment:
- Shipping:
Inventory:1,912
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SN74CB3Q3245ZQNR from Texas Instruments is a high-bandwidth 32-bit FET bus switch with four independent 8-bit sections, rail-to-rail 0–5-V switching at 3.3-V VCC, 5-Ω typical ON-state resistance, 4-pF typical OFF-state I/O capacitance, and bidirectional operation supporting PCI, memory interleaving, and bus isolation applications.
For engineers reviewing the SN74CB3Q3245ZQNR datasheet, SN74CB3Q3245ZQNR pinout, SN74CB3Q3245ZQNR application, or SN74CB3Q3245ZQNR equivalent, key selection criteria include partial-power-down (Ioff) support, 20-MHz max OE switching frequency, −40°C to 85°C industrial temperature range, and LFBGA-48 (ZKE) Pb-free package compatibility with high-speed digital signal gating.
Technical Context
The SN74CB3Q3245ZQNR implements charge-pump-enhanced FET switches per channel to maintain flat, low ON-state resistance across input voltage (0–5 V) and supply (2.3–3.6 V) ranges. Its internal enable logic drives all 32 data paths synchronously via four independent OE inputs (1OE–4OE), enabling flexible partitioning as one 32-bit, two 16-bit, or four 8-bit switches.
Each switch supports undervoltage-tolerant I/Os with built-in undershoot clamp diodes, 5-V-tolerant operation regardless of VCC state (powered up/down), and isolation during power-off via Ioff circuitry that limits backflow current to ≤1 µA at VCC = 0 V.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCC Range | 2.3 V to 3.6 V - Enables interoperability with 2.5-V and 3.3-V logic domains while maintaining 5-V I/O tolerance. |
| ron (Typical) | 5 Ω - Ensures minimal voltage drop and near-zero propagation delay (0.18 ns) for high-fidelity signal pass-through. |
| Cio(OFF) | 4 pF typical - Reduces capacitive loading on buses, preserving signal integrity in high-speed parallel interfaces. |
| fOE Max | 20 MHz - Supports fast enable/disable cycling for dynamic bus segmentation in real-time systems. |
| Ioff | 1 µA at VCC = 0 V - Guarantees safe partial-power-down operation without damaging current flow between live and unpowered subsystems. |
| VI/O Range | 0 V to 5.5 V - Allows seamless interfacing with mixed-voltage systems including 1.2-V, 1.8-V, 2.5-V, 3.3-V, and 5-V signaling standards. |
| Propagation Delay | 0.18 ns (VCC = 2.5 V) - Delivers sub-nanosecond timing for time-critical data gating in broadband communications. |
Pinout & Package
LFBGA-48 (ZKE) package, 6 mm × 6 mm, 0.8-mm pitch, Pb-free, moisture sensitivity level 3. Pin count: 48 terminals. Package supports automated optical inspection and fine-pitch PCB assembly.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1A1–1A8, 1B1–1B8 | Data I/O Port A/B for Section 1 | Bidirectional signal path; no direction control - A and B ports electrically interchangeable when 1OE = L. |
| 1OE | Output Enable for Section 1 | Active-low control; pulls internal switch gate to enable conduction between 1A and 1B ports. |
| 2A1–2A8, 2B1–2B8 | Data I/O Port A/B for Section 2 | Independent 8-bit bus segment; isolated from other sections when respective OE is high. |
| 2OE | Output Enable for Section 2 | Enables/disables only Section 2; allows granular power and signal domain control. |
| 3A1–3A8, 3B1–3B8 | Data I/O Port A/B for Section 3 | Supports differential pair routing or split-bus configurations due to symmetrical pin layout. |
| 3OE | Output Enable for Section 3 | Permits selective activation of memory channels or peripheral interfaces without affecting others. |
| 4A1–4A8, 4B1–4B8 | Data I/O Port A/B for Section 4 | Final 8-bit segment; enables full 32-bit bus isolation when all OEs are controlled independently. |
| 4OE | Output Enable for Section 4 | Allows hot-plug or firmware-controlled bus reconfiguration in embedded controllers. |
| VCC | Supply Voltage | Single 2.3–3.6-V rail powers all logic and switch circuitry; no auxiliary supplies required. |
| GND | Ground Reference | Eight dedicated ground pins distributed across package corners and center for low-inductance return paths. |
| NC | No Internal Connection | Four NC pads (pins A1, C1, H1, J1 per top-view drawing) - must remain unconnected on PCB. |
Key Features
| Feature | Design Value |
|---|---|
| Rail-to-rail 0–5-V switching at 3.3-V VCC | Eliminates level-shifter ICs in mixed-voltage systems such as DDR memory interfaces and legacy PCI bridges. |
| 5-V-tolerant I/Os with device powered up or down | Prevents latch-up and enables hot-swap capability in modular backplane designs without sequencing constraints. |
| Charge-pump gate drive architecture | Maintains flat 5-Ω ron across full VI/O range (0–5 V), ensuring consistent timing and amplitude response. |
| Undershoot clamp diodes on all I/Os | Protects against negative transients down to −1.8 V, reducing need for external TVS components in noisy environments. |
| 4-pF typical OFF-state I/O capacitance | Minimizes signal distortion and crosstalk in high-density parallel buses like address/data multiplexed memory channels. |
Applications
| PCI Interface | Differential Signal Interface |
|---|---|
Use Scenario: Isolating legacy PCI add-in cards from modern host controllers during reset or configuration changes. IC Role / Device Role / Timing Role: Bidirectional 32-bit bus switch providing glitch-free signal gating with sub-ns propagation delay. Use Value: Prevents bus contention and ensures clean power-up sequencing without requiring additional glue logic or level shifters. | Use Scenario: Routing LVDS or RSDS differential pairs through shared backplane traces while maintaining impedance continuity. IC Role / Device Role / Timing Role: Low-capacitance, low-ron analog switch enabling transparent signal pass-through for high-speed differential signals. Use Value: Preserves signal rise/fall times and minimizes jitter accumulation across multiple switch stages in video or test equipment. |
| Memory Interleaving | Bus Isolation |
Use Scenario: Dynamically connecting alternate DRAM banks to a single memory controller based on access patterns. IC Role / Device Role / Timing Role: Four independent 8-bit switches allowing bank-selective enablement with <8 ns turn-on/turn-off times. Use Value: Enables real-time memory bandwidth optimization without interrupting active transfers on other banks. | Use Scenario: Segregating functional blocks (e.g., RF front-end, baseband processor, sensor hub) in battery-powered IoT devices. IC Role / Device Role / Timing Role: Ioff-enabled switch providing galvanic isolation between powered-down and active subsystems. Use Value: Reduces system standby current by >95% versus passive resistive isolation, extending battery life in always-on sensors. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar bus switch applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SN74CBTLV3245PWR | Lower VCC range (2.3–3.6 V same), but no charge pump → ron = 7 Ω typical, Cio(OFF) = 5 pF, fOE = 15 MHz max. | Less suitable for >400-MHz data paths due to higher ron and capacitance; acceptable for 100–200-MHz memory expansion. | Select when cost sensitivity outweighs marginal performance loss and full 500-MHz bandwidth is not required. |
| PI3CH485LE | Same 32-bit architecture, but 1.8–5.5-V VCC range, ron = 6 Ω typical, Cio(OFF) = 4.5 pF, no Ioff support. | Lacks partial-power-down protection; requires external power sequencing for safe multi-rail operation. | Choose for wider supply flexibility in 1.8-V–5-V mixed-signal systems where Ioff is managed externally. |
Compared with SN74CB3Q3245ZQNR, SN74CBTLV3245PWR trades 20% higher ON-resistance and reduced switching speed for lower unit cost, while PI3CH485LE extends voltage range at the expense of Ioff safety - making SN74CB3Q3245ZQNR optimal for industrial-grade hot-pluggable bus architectures demanding both performance and robustness.
Availability
SN74CB3Q3245ZQNR is available at Aetrix Electronics and suitable for PCI interface design, memory interleaving systems, differential signal routing, and bus isolation applications requiring stable component supply across extended temperature and mixed-voltage operating conditions.
Supply support for SN74CB3Q3245ZQNR 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 for industrial, automotive, and communications markets.
The Widebus+™ family, including SN74CB3Q3245ZQNR, was designed specifically for high-bandwidth digital signal routing in systems requiring low-distortion, rail-to-rail switching with robust power-down safety and mixed-voltage interoperability.
FAQ
What is the maximum data bandwidth supported by the SN74CB3Q3245ZQNR?
The SN74CB3Q3245ZQNR supports up to 500 MHz high-bandwidth data paths, validated by TI's characterization of the CB3Q family. This performance stems from its 5-Ω typical ON-state resistance and 4-pF typical OFF-state I/O capacitance, which jointly minimize RC delay and signal distortion. The SN74CB3Q3245ZQNR achieves this bandwidth while maintaining rail-to-rail 0–5-V switching at 3.3-V VCC, making it suitable for PCI Express Gen 1–2 sideband and DDR2 memory channel applications.
Does the SN74CB3Q3245ZQNR support partial-power-down operation?
Yes, the SN74CB3Q3245ZQNR fully supports partial-power-down operation via its Ioff circuitry. When VCC = 0 V, Ioff limits current backflow to ≤1 µA even with 0–5.5-V signals applied to I/O ports. This feature ensures safe isolation between powered and unpowered subsystems - critical in hot-pluggable modules, battery-backed peripherals, and modular computing platforms where SN74CB3Q3245ZQNR is deployed for bus segmentation.
What is the pin-compatible replacement for SN74CB3Q3245ZQNR in LFBGA-48?
There is no documented pin-compatible replacement for SN74CB3Q3245ZQNR in the LFBGA-48 (ZKE) package. While SN74CB3Q3245GKER shares identical pinout and functionality, it uses the GKE package (non-Pb-free). The SN74CB3Q3245ZQNR is uniquely specified with Pb-free ZKE packaging and −40°C to 85°C operation. Substituting other variants requires verification of thermal profile compatibility, solder paste specification, and JEDEC moisture sensitivity level (MSL 3) compliance for the SN74CB3Q3245ZQNR.
How does the charge-pump architecture in SN74CB3Q3245ZQNR improve switching performance?
The charge-pump architecture in SN74CB3Q3245ZQNR elevates the gate voltage of the internal FET pass transistors above VCC, ensuring strong enhancement-mode conduction across the full 0–5-V I/O voltage range. This results in flat 5-Ω typical ON-state resistance independent of input voltage - unlike standard FET switches whose ron rises sharply near rail extremes. Consequently, the SN74CB3Q3245ZQNR delivers consistent sub-ns propagation delay and minimal signal attenuation, directly enabling its 500-MHz bandwidth rating.
Can the SN74CB3Q3245ZQNR be used for analog signal switching?
Yes, the SN74CB3Q3245ZQNR supports both digital and analog applications, as explicitly stated in its datasheet. Its low and flat ON-state resistance (5 Ω typical), low OFF-state capacitance (4 pF), and rail-to-rail signal handling (0–5 V) make it suitable for low-distortion analog signal gating - such as audio routing, sensor multiplexing, and test equipment signal path selection. However, it is not optimized for precision DC accuracy or ultra-low leakage; for those requirements, dedicated analog switches like TMUX series should be evaluated alongside SN74CB3Q3245ZQNR.
SN74CB3Q3245ZQNR Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- 74CB
- Package/Case:
- 20-VFBGA
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Type:
- Bus Switch
- Circuit:
- 8 x 1:1
- Independent Circuits:
- 1
- Current - Output High, Low:
- -
- Voltage Supply Source:
- Single Supply
- Voltage - Supply:
- 2.3V ~ 3.6V
- Operating Temperature:
- -40°C ~ 85°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 20-BGA MICROSTAR JUNIOR (4x3)
SN74CB3Q3245ZQNR FAQ
1.How can I place an order for SN74CB3Q3245ZQNR through Aetrix?
Please submit a Request for Quotation (RFQ) for SN74CB3Q3245ZQNR 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 SN74CB3Q3245ZQNR reliable?
The price and inventory of SN74CB3Q3245ZQNR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SN74CB3Q3245ZQNR is usually 5 days.
3.What payment methods are accepted for SN74CB3Q3245ZQNR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SN74CB3Q3245ZQNR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SN74CB3Q3245ZQNR?
SN74CB3Q3245ZQNR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SN74CB3Q3245ZQNR 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 SN74CB3Q3245ZQNR?
For technical support, including SN74CB3Q3245ZQNR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SN74CB3Q3245ZQNR requirements.
6.How does Aetrix verify that SN74CB3Q3245ZQNR is sourced from the original manufacturer or authorized distributors?
All SN74CB3Q3245ZQNR 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 SN74CB3Q3245ZQNR meets industry standards.
7.What is the process for return or replacement of SN74CB3Q3245ZQNR?
All SN74CB3Q3245ZQNR units undergo pre-shipment inspection (PSI). If there is an issue with SN74CB3Q3245ZQNR, 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 SN74CB3Q3245ZQNR part is unused and in its original packaging.
Return procedure for SN74CB3Q3245ZQNR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SN74CB3Q3245ZQNR 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…
