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Renesas QS3244PAG8
- Part No.:
- QS3244PAG8
- Manufacturer:
- Renesas
- Category:
- Signal Switches, Multiplexers, Decoders
- Package:
- 20-TSSOP (0.173", 4.40mm Width)
- Datasheet:
-
QS3244PAG8.pdf
- Description:
- IC BUS SWITCH 4 X 1:1 20TSSOP
- Quantity:
- Payment:
- Shipping:
Inventory:2,567
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Product details
Overview
QS3244PAG8 from Renesas Electronics is an 8-bit high-speed CMOS bus switch with TTL-compatible pinout, 5Ω ON resistance, zero propagation delay, and industrial temperature range (–40°C to +85°C). It functions as a bidirectional signal path controller for hot-swappable I/O isolation in 5V/3.3V mixed-voltage systems.
For engineers reviewing the QS3244PAG8 datasheet, QS3244PAG8 pinout, QS3244PAG8 application, or QS3244PAG8 equivalent, key selection criteria include ON-resistance stability across input voltage, undershoot clamp diode protection, enable-controlled dual 4-bit channel isolation, and compatibility with legacy 74FCT244-based layouts.
Technical Context
The QS3244PAG8 implements eight independent N-channel FET switches without intrinsic body diodes to VCC, enabling true bidirectional signal flow with no DC blocking. Each switch exhibits 5Ω typical ON resistance at VCC = 5V and 30mA drive, supporting sub-nanosecond RC-limited timing.
Two independent active-low enable inputs (1G, 2G) control two groups of four I/O pairs (1A1–1Y1 through 1A4–1Y4 and 2A1–2Y1 through 2A4–2Y4), allowing selective bus segmentation. Undershoot clamp diodes on all A/Y and G pins protect against –3V transient spikes.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| ON Resistance | 5 Ω typical at VCC = 5V, 30mA - enables near-zero insertion loss and minimal signal distortion in high-speed data paths |
| Propagation Delay | 0.25 ns max - contributes negligible timing overhead beyond system RC delay, preserving setup/hold margins |
| Input Voltage Range | –0.5 V to +7 V - supports hot-swap transients and 5V-to-3.3V level translation without external biasing |
| Off-State Leakage | ±1 μA max - ensures robust signal isolation between enabled/disabled channels during power sequencing |
| Operating Temperature | –40°C to +85°C - validated for industrial-grade embedded control and communications equipment |
| Power Supply Current | 3 μA quiescent - reduces standby power in battery-backed or energy-sensitive subsystems |
| Capacitance (OFF) | 7 pF max per channel - minimizes loading on upstream drivers and improves signal integrity at >100 MHz |
Pinout & Package
QS3244PAG8 is housed in a 20-pin TSSOP package (PAG suffix), 4.4 mm × 6.5 mm body, 0.65 mm pitch, RoHS-compliant and green-processed.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1G, 2G | Active-low output enable | Controls conduction state of Group 1 (pins 2–9) and Group 2 (pins 12–19); logic LOW enables corresponding Yx outputs |
| 1A1–1A4, 2A1–2A4 | Data input/output (bidirectional) | Pass signals directly to paired Yx pins when respective G is LOW; high-impedance when disabled |
| 1Y1–1Y4, 2Y1–2Y4 | Data input/output (bidirectional) | Electrically identical to corresponding Ax pins; no directionality or internal buffering |
| VCC | Positive supply | 5V ±5% only; powers internal clamp diodes and gate drive - not tolerant of 3.3V-only operation |
| GND | Ground reference | Return path for all I/O and control currents; must be low-inductance for ground-bounce suppression |
Key Features
| Feature | Design Value |
|---|---|
| No intrinsic body diode to VCC | Eliminates unintended current paths during voltage sequencing - critical for safe hot-plug insertion into live backplanes |
| Undershoot clamp diodes | Protects all A/Y/G pins against –3V transients - prevents latch-up in noisy industrial environments |
| Pin compatibility with 74FCT244 | Enables drop-in replacement in existing 74FCT244-based PCB layouts without redesign or re-spin |
| Zero ground bounce | Minimizes simultaneous switching noise - preserves signal integrity in dense digital systems with shared ground planes |
| 5Ω ON resistance | Ensures <10 mV voltage drop at 20 mA - maintains TTL logic thresholds across full operating temperature range |
Applications
| Hot-Swappable Backplane Interface | Voltage-Level Translating Bus Isolation |
|---|---|
Use Scenario: Inserting/removing mezzanine cards in powered telecom or industrial chassis without disrupting main system operation. IC Role / Device Role / Timing Role: Bidirectional signal gate isolating card-side and backplane-side buses during insertion/removal sequences. Use Value: Prevents bus contention and ground bounce via controlled enable timing and clamped I/Os - meets IEC 61000-4-2 Level 4 ESD immunity requirements. | Use Scenario: Interfacing 5V microcontrollers to 3.3V FPGA peripherals in mixed-supply embedded systems. IC Role / Device Role / Timing Role: Passive voltage translator enabling logic-level compatibility without active level-shifting circuitry or timing skew. Use Value: Maintains signal fidelity up to 200 MHz with <0.25 ns added delay - eliminates need for dual-supply translators or series resistors. |
| Low-Power Clock Gating | Capacitance-Reduced Data Path Switching |
Use Scenario: Dynamically disabling clock distribution to idle IP blocks in battery-powered IoT edge nodes. IC Role / Device Role / Timing Role: Low-leakage, low-capacitance switch inserted in clock tree to gate unused domains. Use Value: Reduces dynamic power by >95% in gated domains while preserving clock edge integrity - achieves sub-μA sleep current. | Use Scenario: Selecting between multiple sensor interfaces sharing a single ADC input in automotive body controllers. IC Role / Device Role / Timing Role: High-isolation analog/digital multiplexer minimizing crosstalk and load capacitance on sensitive measurement lines. Use Value: Limits OFF-state capacitance to 7 pF - improves settling time by 3× versus standard logic buffers in 12-bit SAR ADC applications. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar bus switching applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SN74CBT3244PWR | Higher typical RON (7Ω), no undershoot clamps, 3.3V-only supply | Limited to 3.3V systems; unsuitable for 5V hot-swap or mixed-voltage translation | Prefer QS3244PAG8 where 5V tolerance, clamping, or industrial temp range is required |
| 74FCT244CTSO20 | Traditional TTL buffer with propagation delay (~5 ns), higher ICCQ (10 μA), no hot-swap protection | Provides logic amplification but adds delay and noise; lacks isolation and transient protection | Choose QS3244PAG8 when zero-delay pass-through, low leakage, or ESD-hardened I/O is mandatory |
Compared with SN74CBT3244PWR and 74FCT244CTSO20, QS3244PAG8 uniquely delivers 5V-tolerant bidirectional switching with integrated undershoot protection and sub-ns timing - essential for robust hot-plug and mixed-voltage interconnects.
Availability
QS3244PAG8 is available at Aetrix Electronics and suitable for hot-swappable backplane interfaces, voltage-level translating bus isolation, and low-power clock gating requiring stable component supply across industrial temperature ranges.
Supply support for QS3244PAG8 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 connectivity solutions for automotive, industrial, and enterprise applications.
QS3244PAG8 belongs to the QuickSwitch® bus switch product line, engineered specifically for zero-delay, high-isolation signal routing in hot-pluggable and mixed-voltage digital systems.
FAQ
What is the maximum allowable input voltage on QS3244PAG8 A/Y pins?
The QS3244PAG8 supports DC input voltages from –0.5 V to +7 V on all A/Y and control pins. This allows safe operation during hot-swap events where transient undershoot or overshoot may occur. The integrated clamp diodes limit negative excursions to –3 V for pulse widths ≤20 ns, protecting against ESD and inductive kickback without external components.
Does QS3244PAG8 support true bidirectional signal flow?
Yes, QS3244PAG8 implements enhancement-mode N-channel FETs with no inherent body diode to VCC, enabling symmetrical, low-resistance conduction in both directions. Signal integrity is preserved regardless of whether the driving source is connected to the A or Y side - confirmed by identical RON, capacitance, and timing specs for both terminals.
Can QS3244PAG8 operate with a 3.3V supply instead of 5V?
No, QS3244PAG8 requires a 5V ±5% supply (4.75V–5.25V) on VCC. Its internal gate drive and clamp diode structure are optimized for 5V operation. Applying 3.3V will result in incomplete turn-on, elevated RON, and failure to meet guaranteed timing or leakage specifications - the device is not specified for 3.3V-only use.
How does QS3244PAG8 achieve zero ground bounce?
QS3244PAG8 eliminates ground bounce by using a low-impedance, diode-free FET architecture with tightly controlled switching edges and minimized internal charge injection. Unlike conventional buffers, it draws no significant transient current during switching - ICCD is only 0.25 mA/MHz - preventing localized ground potential shifts that corrupt adjacent signals.
Is QS3244PAG8 pin-compatible with standard 74-series logic devices?
Yes, QS3244PAG8 is explicitly pin-compatible with 74FCT244, 74F244, and 74FCT244T in the same 20-pin SOIC, QSOP, or TSSOP footprint. Pin assignments for enables (1G/2G), I/O pairs (1A1/1Y1 through 2A4/2Y4), VCC, and GND match exactly - enabling direct replacement without PCB modification.
QS3244PAG8 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Renesas
- Series:
- -
- Package/Case:
- 20-TSSOP (0.173", 4.40mm Width)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Type:
- Bus Switch
- Circuit:
- 4 x 1:1
- Independent Circuits:
- 2
- 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:
- 20-TSSOP
QS3244PAG8 FAQ
1.How can I place an order for QS3244PAG8 through Aetrix?
Please submit a Request for Quotation (RFQ) for QS3244PAG8 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 QS3244PAG8 reliable?
The price and inventory of QS3244PAG8 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for QS3244PAG8 is usually 5 days.
3.What payment methods are accepted for QS3244PAG8?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for QS3244PAG8 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for QS3244PAG8?
QS3244PAG8 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your QS3244PAG8 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 QS3244PAG8?
For technical support, including QS3244PAG8 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your QS3244PAG8 requirements.
6.How does Aetrix verify that QS3244PAG8 is sourced from the original manufacturer or authorized distributors?
All QS3244PAG8 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 QS3244PAG8 meets industry standards.
7.What is the process for return or replacement of QS3244PAG8?
All QS3244PAG8 units undergo pre-shipment inspection (PSI). If there is an issue with QS3244PAG8, 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 QS3244PAG8 part is unused and in its original packaging.
Return procedure for QS3244PAG8:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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