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Renesas QS34X245Q3G
- Part No.:
- QS34X245Q3G
- Manufacturer:
- Renesas
- Category:
- Signal Switches, Multiplexers, Decoders
- Package:
- 80-FSOP (0.154", 3.90mm Width)
- Datasheet:
-
QS34X245Q3G.pdf
- Description:
- IC BUS SWITCH 8 X 1:1 80QVSOP
- Quantity:
- Payment:
- Shipping:
Inventory:4,333
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Product details
Overview
QS34X245Q3G from Renesas Electronics is a 32-bit high-speed CMOS bus switch with flow-through pinout, zero propagation delay, 5Ω typical ON-resistance at VCC = 5V, and industrial temperature range (–40°C to +85°C). It enables bidirectional voltage translation between 5V and 3.3V buses and supports hot-swapping in server backplanes.
For engineers reviewing the QS34X245Q3G datasheet, QS34X245Q3G pinout, QS34X245Q3G application, or QS34X245Q3G equivalent, key selection criteria include guaranteed TTL-compatible control inputs, undershoot clamp diodes on all I/Os, 0.25ns max propagation delay, and 80-pin MilliPaQ™ package compatibility with dense PCB layouts.
Technical Context
The QS34X245Q3G implements 32 independent N-channel FET switches with no inherent body diode to VCC, enabling true bidirectional signal pass-through without DC blocking. Each switch is controlled by one of four OE pins (OE1–OE4), allowing segmented bus isolation.
It operates with zero ground bounce and zero propagation delay beyond RC time constant (≤0.25ns for 50pF load), driven solely by its 5Ω typical RON and low input/output capacitance (7–8pF per channel off-state). Control logic uses TTL-compatible thresholds (VIH ≥2V, VIL ≤0.8V) and draws ≤1.5mA per active OE input.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCC Range | 5.0V ±5% - supports standard 5V logic rails with margin for supply variation |
| RON (Typ) | 5Ω at VCC = 5V, VIN = 0V - ensures minimal signal attenuation and impedance matching for high-speed buses |
| tPLH/tPHL (Max) | 0.25ns - adds negligible delay beyond driver/load RC, preserving timing integrity in 100+ MHz systems |
| Operating Temp | –40°C to +85°C - qualified for industrial and telecom infrastructure environments |
| Input Capacitance | 3–4pF (control), 7–8pF (switch channels off) - reduces loading on upstream drivers and eases timing closure |
| Undershoot Clamp | Integrated on all A/B/OE pins - protects against negative transients down to –3V (20ns pulse), eliminating external TVS needs |
| Power Dissipation | 1.4W max at TA = 70°C - enables operation in thermally constrained modules without forced air |
Pinout & Package
QS34X245Q3G is housed in an 80-pin MilliPaQ™ package - a small-outline, surface-mount solution optimized for 32-bit bus density. Pin layout follows flow-through topology to minimize trace crossovers and reduce parasitic inductance.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| OEn (OE1–OE4) | Active-low enable control | Each OE controls 8 adjacent A/B pairs; low = conductive path, high = Hi-Z isolation |
| An (A0–A31) | Bidirectional data I/O | Connects directly to local bus segment; no direction pin required due to symmetric FET structure |
| Bn (B0–B31) | Bidirectional data I/O | Connects to remote bus segment; supports 5V↔3.3V level shifting without external resistors |
| VCC | Power supply | Single 5V rail powers all switches and control logic; no separate I/O voltage required |
| GND | Ground reference | Four dedicated GND pins distributed across package for low-impedance return paths and noise suppression |
| NC | No-connect | Unbonded pins; must remain unconnected per design - not usable as spare I/O or thermal pads |
Key Features
| Feature | Design Value |
|---|---|
| Zero-propagation-delay switching | RC-limited delay <0.25ns (CL=50pF) - preserves setup/hold timing in DDR and PCIe interconnects |
| Enhanced N-channel FET architecture | No intrinsic source-body diode to VCC - prevents unintended current paths during hot-swap insertion |
| Flow-through pinout | A/B signals enter and exit opposite edges - eliminates layer jumps and vias in 4-layer PCBs |
| TTL-compatible control inputs | VIH ≥2V, VIL ≤0.8V - interfaces directly with legacy 5V microcontrollers and FPGAs without level shifters |
| Integrated undershoot clamps | Clamps to –3V (20ns) on all A/B/OE pins - meets IEC 61000-4-2 Level 4 ESD immunity requirements |
Applications
| Server Backplane Isolation | Hot-Swappable Module Interface |
|---|---|
Use Scenario: Isolating CPU/memory subsystems from expansion slots during live insertion/removal in rack-mounted servers. IC Role / Device Role / Timing Role: Bidirectional bus switch enabling glitch-free disconnection of 32-bit address/data lines while maintaining signal integrity. Use Value: Prevents system lockup or data corruption during hot-swap events via zero-delay switching and undershoot protection. | Use Scenario: Enabling safe insertion of PCIe or SATA mezzanine cards into embedded carrier boards without powering down. IC Role / Device Role / Timing Role: Voltage-translating bus gate that isolates 5V host logic from 3.3V peripheral logic during power sequencing. Use Value: Eliminates need for discrete level shifters and external clamping diodes, reducing BOM count by 7 components per interface. |
| Industrial PLC I/O Expansion | Test Equipment Signal Routing |
Use Scenario: Adding modular analog/digital I/O banks to programmable logic controllers operating in harsh factory environments. IC Role / Device Role / Timing Role: High-reliability bus switch providing galvanic isolation between controller core and field-side peripherals. Use Value: Withstands –40°C to +85°C ambient and suppresses ground bounce-induced false triggers in noisy 24VDC industrial settings. | Use Scenario: Reconfigurable signal path selection in automated test equipment for multi-DUT parallel testing. IC Role / Device Role / Timing Role: Low-capacitance, low-RON multiplexer routing clock, trigger, and data lines between instruments and devices under test. Use Value: Enables sub-nanosecond timing resolution and maintains signal fidelity up to 500MHz due to <8pF off-state capacitance. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar bus switching applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SN74CBT3245APM | 80-pin TSSOP; RON = 6Ω typ; tPLH = 0.25ns max; no integrated undershoot clamps | Lacks built-in transient protection - requires external diodes for IEC 61000-4-2 compliance | Preferred where board space allows larger TSSOP and cost sensitivity outweighs protection integration |
| PI3CH3245LEX | 80-pin QFN; RON = 7Ω typ; supports 3.3V-only VCC; VIH = 2.0V min (same) | Not 5V-tolerant on I/O - incompatible with mixed-voltage hot-swap where 5V signaling persists | Selected when system operates exclusively at 3.3V and thermal performance demands QFN over MilliPaQ™ |
Compared with SN74CBT3245APM and PI3CH3245LEX, QS34X245Q3G uniquely combines 5V tolerance, integrated undershoot clamps, and MilliPaQ™ footprint - making it the only option qualified for industrial hot-swap without supplemental protection circuitry.
Availability
QS34X245Q3G is available at Aetrix Electronics and suitable for server backplane isolation, industrial PLC I/O expansion, and automated test equipment requiring stable component supply and long-term lifecycle support.
Supply support for QS34X245Q3G 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
Renesas Electronics Corporation is a global semiconductor leader delivering microcontrollers, analog, power, and SoC solutions for automotive, industrial, and enterprise applications.
The QS34X245Q3G belongs to Renesas' QuickSwitch® MultiWidth™ bus switch family, engineered specifically for high-density, low-latency board-level interconnects in space-constrained computing and communications systems.
FAQ
What is the maximum operating voltage for QS34X245Q3G?
The QS34X245Q3G supports a supply voltage range of –0.5V to +7V on all terminals except VCC, and –0.5V to +7V on VCC pins. Its specified operational VCC is 5.0V ±5%, and it tolerates transient overvoltage up to +7V without damage. This rating enables robustness against power rail overshoot during hot-plug events and ensures compatibility with legacy 5V logic families.
Does QS34X245Q3G support voltage translation between 5V and 3.3V buses?
Yes, QS34X245Q3G supports bidirectional 5V-to-3.3V voltage translation without external components. Its enhanced N-channel FET architecture lacks a body diode to VCC, preventing reverse current flow, and its TTL-compatible control inputs (VIH ≥2V, VIL ≤0.8V) interface directly with both 5V and 3.3V logic. The device passes signals with ≤0.25ns added delay and maintains signal integrity across the translation boundary.
How many independent enable controls does QS34X245Q3G provide?
QS34X245Q3G provides four independent active-low Output Enable inputs: OE1, OE2, OE3, and OE4. Each controls eight adjacent A/B channel pairs (e.g., OE1 controls A0–A7/B0–B7), enabling granular bus segmentation. This allows partial isolation of 32-bit data paths - for example, disabling memory address lines while keeping data lines active - improving system-level power management and fault containment.
Is QS34X245Q3G compatible with RoHS and lead-free assembly processes?
Yes, QS34X245Q3G is RoHS-compliant and qualified for lead-free reflow soldering. The "Q3G" suffix explicitly denotes green (halogen-free, lead-free) packaging in the 80-pin MilliPaQ™ format. It meets JEDEC J-STD-020 moisture sensitivity level 3 and supports peak reflow temperatures up to 260°C, making it suitable for modern SMT production lines without process modification.
What is the thermal performance of QS34X245Q3G in sustained operation?
QS34X245Q3G has a maximum power dissipation of 1.4W at TA = 70°C and a storage temperature range of –65°C to +150°C. Its thermal resistance (θJA) is optimized for the MilliPaQ™ package, supporting continuous operation at full 32-bit switching in industrial enclosures with natural convection. Derating begins above 70°C ambient, and full specification compliance is maintained from –40°C to +85°C without thermal throttling.
QS34X245Q3G Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Renesas
- Series:
- 34X
- Package/Case:
- 80-FSOP (0.154", 3.90mm Width)
- Packaging:
- Tube
- Product Status:
- Obsolete
- Type:
- Bus Switch
- Circuit:
- 8 x 1:1
- Independent Circuits:
- 4
- Current - Output High, Low:
- -
- Voltage Supply Source:
- Single Supply
- Voltage - Supply:
- 4.75V ~ 5.25V
- Operating Temperature:
- -40°C ~ 85°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 80-QVSOP
QS34X245Q3G FAQ
1.How can I place an order for QS34X245Q3G through Aetrix?
Please submit a Request for Quotation (RFQ) for QS34X245Q3G 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 QS34X245Q3G reliable?
The price and inventory of QS34X245Q3G are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for QS34X245Q3G is usually 5 days.
3.What payment methods are accepted for QS34X245Q3G?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for QS34X245Q3G transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for QS34X245Q3G?
QS34X245Q3G orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your QS34X245Q3G 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 QS34X245Q3G?
For technical support, including QS34X245Q3G datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your QS34X245Q3G requirements.
6.How does Aetrix verify that QS34X245Q3G is sourced from the original manufacturer or authorized distributors?
All QS34X245Q3G 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 QS34X245Q3G meets industry standards.
7.What is the process for return or replacement of QS34X245Q3G?
All QS34X245Q3G units undergo pre-shipment inspection (PSI). If there is an issue with QS34X245Q3G, 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 QS34X245Q3G part is unused and in its original packaging.
Return procedure for QS34X245Q3G:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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