SN74HC126QPWRQ1 - Quad 3-State Buffer AEC-Q100 | Texas Instruments
부품 번호: SN74HC126QPWRQ1 ✓ 활성| 수량 | 단가 | 합계 |
|---|---|---|
| 1 | $0.62 | $0.62 |
| 10 | $0.55 | $5.50 |
| 100 | $0.41 | $41.00 |
| 500 | $0.33 | $165.00 |
| 1,000 | $0.27 | $270.00 |
| 3,000 | $0.23 | $690.00 |
SN74HC126QPWRQ1 개요
A buffer with 3-state outputs is a digital logic element that passes its input level to the output when enabled and presents a high-impedance (Hi-Z) state when disabled, allowing multiple devices to share a common bus. Within the logic hierarchy, it belongs to the buffer/line-driver family of high-speed CMOS (HC) logic, itself a branch of the broader CMOS voltage-regulated logic category used in nearly every digital system.
Key features include four independent 1-bit buffers with separate OE control per channel, active-high enable inputs (the OE low state disables the output), and automotive qualification per AEC-Q100 for operation in harsh environments. The HC CMOS process delivers low static power consumption and balanced drive characteristics across the 2 V to 6 V operating range, with TTL-friendly noise margins at 5 V.
The 74HC126 architecture derives from the industry-standard 74126 pinout: each gate passes input A to output Y when OE is high; when OE is low the output enters Hi-Z. TI recommends tying OE to GND through a pull-down resistor during power-up and power-down to guarantee the high-impedance state, preventing bus contention in shared-bus systems such as microcontroller data buses and memory interfaces.
Typical applications include automotive body electronics and infotainment bus isolation, industrial PLC I/O line driving, and microcontroller GPIO buffering where tri-state control prevents driver conflicts. The TSSOP-14 package suits space-constrained automotive modules.
Design consideration: keep unused inputs (especially OE) tied to a defined logic level through a pull resistor; floating enables can cause unpredictable bus contention and increased supply current.
This page synthesizes distributor pricing, drop-in alternatives including Schmitt-trigger and AHC variants, and practical design notes not found in the manufacturer datasheet. Pricing data is as of 2026-09-10.
드롭인 대체품: SN74HC126QPWRQ1 — 동일 패키지, 핀 호환. PCB 재작업이 필요한 다른 패키지 부품은 제외됩니다.
이 시리즈의 변형
다음과 드롭인 호환되는 동일 시리즈 모델: SN74HC126QPWRQ1 (동일 폼 팩터 및 풋프린트) — 차이점: Input Type, Operating Temperature, Output Type, Package, Qualification.
빠른 비교 도구 — 나란히 비교할 대체 부품을 선택하십시오:
SN74HCS126QPWRQ1
✅ 드롭인✓ 재고 있음
$0.35 / 개
데이터시트 보기 →SN74AHC126QPWRQ1
✅ 드롭인📋 참조 대체품 (카탈로그에 없음)
SN74AHCT126QPWRQ1
✅ 드롭인📋 참조 대체품 (카탈로그에 없음)
SN74HC126PW
✅ 드롭인 ⚠️ 사양 미검증📋 참조 대체품 (카탈로그에 없음)
SN74HCS126QPWRQ1
✅ 드롭인✓ 재고 있음
$0.35 / 개
데이터시트 보기 →SN74HC126QPWRQ1 최대 정격 & 전기적 특성
| 기능 | Quadruple bus buffer with 3-state outputs (non-inverting) |
| Number of Elements | 4 |
| Bits per Element | 1 |
| 출력 유형 | 3-State |
| Input Type | Standard CMOS (HC) |
| Supply Voltage Range | 2 V to 6 V |
| Output Enable | Active-high, per channel (OE low disables output) |
| Qualification | AEC-Q100 (automotive) |
| 패키지 | TSSOP-14 (PW) |
| 실장 유형 | Surface Mount |
| 동작 온도 | -40C to +125C (automotive range) |
| Logic Family | 74HC (High-Speed CMOS) |
| RoHS 상태 | Compliant |
SN74HC126QPWRQ1 핀 구성
| 핀 1 | 1OE — Output enable for buffer 1 (active high) |
| 핀 2 | 1A — Input of buffer 1 |
| 핀 3 | 1Y — 3-state output of buffer 1 |
| 핀 4 | 2OE — Output enable for buffer 2 (active high) |
| 핀 5 | 2A — Input of buffer 2 |
| 핀 6 | 2Y — 3-state output of buffer 2 |
| 핀 7 | GND — Ground |
| 핀 8 | 3Y — 3-state output of buffer 3 |
| 핀 9 | 3A — Input of buffer 3 |
| 핀 10 | 3OE — Output enable for buffer 3 (active high) |
| 핀 11 | 4Y — 3-state output of buffer 4 |
| 핀 12 | 4A — Input of buffer 4 |
| 핀 13 | 4OE — Output enable for buffer 4 (active high) |
| 핀 14 | VCC — Power supply, 2 V to 6 V |
일반적인 애플리케이션
SN74HC126QPWRQ1 적합 용도: 6 애플리케이션s: Automotive Bus Isolation, Microcontroller GPIO Buffering, Industrial PLC I/O Modules, Memory and Peripheral Bus Sharing, Automotive Infotainment Modules, Test and Measurement Fixtures.
Automotive Bus Isolation
The SN74HC126QPWRQ1 fits automotive bus isolation because its AEC-Q100 qualification, -40C to +125C operating range, and 2 V to 6 V supply directly match body-control-module and gateway power rails. Each buffer's independent active-high OE pin lets the MCU tri-state a shared data or control bus during reset, fault, or diagnostics, preventing bus contention between multiple drivers. Placed between the MCU GPIO bank and a shared harness signal, the device adds no propagation-budget burden at typical HC speeds while providing a guaranteed Hi-Z state; the datasheet-recommended pull-down on OE ensures the bus stays released during power-up and power-down transients.
추천
Microcontroller GPIO Buffering
For MCU GPIO buffering, the SN74HC126QPWRQ1 provides four independently enabled 3-state drivers that offload drive current from sensitive microcontroller pins. When the 5 V MCU rail feeds the buffer, HC CMOS inputs switch at mid-supply thresholds compatible with 3.3 V logic at relaxed noise margins, and outputs deliver stronger drive than typical MCU GPIOs on capacitive harness or cable loads. The per-channel OE architecture supports one-wire or shared-line patterns where a single MCU pin must alternate between driving and releasing the line. Keep total prop-delay of the HC buffer in the timing budget and add 0.1 uF decoupling at pin 14.
추천
Industrial PLC I/O Modules
In industrial PLC I/O modules, the SN74HC126QPWRQ1 serves as a tri-state line driver between the logic controller and field-side circuitry on a 5 V rail. Its high-impedance output state allows multiple plug-in I/O channels to share a backplane data or enable line, and the 6 V maximum rating adds headroom against industrial rail tolerances. HC CMOS static current is negligible in the idle state, which matters in high-channel-count racks. When field signals arrive through long cables with slow edges, substitute the pin-compatible SN74HCS126QPWRQ1 whose Schmitt-trigger inputs reject ringing; both are footprint-identical, enabling one PCB for both variants.
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Memory and Peripheral Bus Sharing
The SN74HC126QPWRQ1 is well suited to memory and peripheral bus sharing, the classic 74126 use case. Multiple peripherals can drive a common data bus because each buffer's OE pin is gated by a decoder output, guaranteeing at most one active driver. With OE tied low through a pull-down during power-up, the datasheet-required Hi-Z default prevents contention while MCU supplies stabilize. HC propagation delay at 5 V is short enough for most parallel peripheral timing at moderate clock rates; for tight-setup buses, the pin-compatible SN74AHC126QPWRQ1 provides faster edges in the identical TSSOP-14 footprint, allowing a speed upgrade without respin.
추천
Automotive Infotainment Modules
Infotainment head units and display modules use the SN74HC126QPWRQ1 to gate enable and control lines between the SoC domain and power-management or backlight circuitry. The -40C to +125C AEC-Q100 range covers cabin and near-dashboard environments, and the tri-state outputs let the module release control lines during software reset so analog sections default safely off. On the 5 V rail, HC inputs cleanly resolve SoC GPIO levels and the buffers drive status LEDs or enable pins directly. Because OE polarity is active-high, firmware-controlled enables map naturally to a logic-high-means-on convention used by most power sequencing schemes in these modules.
추천
Test and Measurement Fixtures
In test and measurement fixtures, the SN74HC126QPWRQ1 implements addressable, tri-state stimulus channels: a fixture controller enables one of many buffer outputs onto a shared line while all others present high impedance, so the device-under-test sees a single defined driver. The 2 V to 6 V supply range lets one fixture design test parts at 3.3 V, 5 V, and margin conditions by simply varying the buffer supply. HC inputs tolerate the slow edges of relay-switched signal paths in many fixture cases, though the SN74HCS126QPWRQ1 Schmitt variant is the safer choice where relay settling produces sub-threshold ramps. Q1 qualification adds robustness for production-line environments.
추천
추천 제품 요약
엔지니어링 참조 데이터: SN74HC126QPWRQ1 — 비교, 설계 지침 및 규정 준수 정보.
선택 가이드
대체품과의 비교
| 파라미터 | 이 제품 | SN74HCS126QPWRQ1 | SN74AHC126QPWRQ1 | SN74AHCT126QPWRQ1 | SN74HC126PW |
|---|---|---|---|---|---|
| Package | TSSOP-14 (PW) | TSSOP-14 (PW) - same | TSSOP-14 (PW) - same | TSSOP-14 (PW) - same | TSSOP-14 (PW) - same |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Input Stage | Standard CMOS (HC) | Schmitt-trigger | Standard CMOS (AHC) | TTL-compatible thresholds | Standard CMOS (HC) |
| Supply Voltage Range | 2 V to 6 V | 2 V to 6 V | 2 V to 5.5 V | 4.5 V to 5.5 V | 2 V to 6 V |
| AEC-Q100 Qualification | Yes | Yes | Yes | Yes | No (commercial grade) |
| Speed / Drive | HC family (moderate) | HC family (moderate) | Faster (AHC family) | Faster (AHCT family) | HC family (moderate) |
| Relative Cost | Low | Moderate (Schmitt feature premium) | Moderate (faster process premium) | Moderate | Lowest (non-automotive) |
주요 차별점
- Wide 6 V supply tolerance (vs SN74AHC126QPWRQ1)
- Lowest cost in same footprint (vs SN74HCS126QPWRQ1)
- Automotive qualification retained (vs SN74HC126PW)
설계 노트
TI datasheet guidance for the 74x126 family: tie each OE input to GND through a pull-down resistor (e.g. 10 kOhm) so outputs default to high impedance during power-up and power-down. A floating OE can glitch high mid-ramp, causing two drivers to contend on a shared bus and potentially overstress outputs. Never leave buffer inputs floating either - unused A inputs should be tied to GND or VCC to prevent oscillation and excess ICC.
Estimated: HC CMOS static supply current is near zero, but dynamic ICC scales with frequency and load capacitance per P = C*V^2*f. For four outputs driving 50 pF loads at 5 V and 10 MHz, dissipation is roughly 4 * 50e-12 * 25 * 1e7 = 50 mW - negligible in TSSOP-14, so no thermal design is required. Add a 0.1 uF ceramic decoupling capacitor at pin 14 close to the device, plus bulk capacitance per board rail.
On long harness or cable-driven signals, the standard HC input lacks hysteresis and can oscillate on slow edges near the switching threshold. If input rise/fall times approach the HC family's specified maximum, switch to the pin-identical SN74HCS126QPWRQ1 with Schmitt-trigger inputs - no layout change needed. Series termination (22-33 ohm) on outputs driving unterminated cables reduces ringing.
규정 준수 정보
AEC-Q100 qualification per the Q1 suffix and TI automotive product listing. RoHS/lead-free per current TI catalog production; REACH and halogen declarations should be confirmed via TI material certificates.
