SN74HCS541QPWRQ1 - AEC-Q100 Octal Buffer 3-State | TI
MPN: SN74HCS541QPWRQ1 ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $0.62 | $0.62 |
| 10 | $0.56 | $5.60 |
| 100 | $0.44 | $44.00 |
| 500 | $0.36 | $180.00 |
| 1,000 | $0.3 | $300.00 |
SN74HCS541QPWRQ1 Overview
An octal buffer/line driver is a digital logic IC in the CMOS logic family that provides signal buffering, drive-current amplification, and bus isolation between a controller and its loads. Within the logic hierarchy, it belongs to the buffer and line-driver category of specialty logic, sitting between simple gates and full bus transceivers. The 3-state (tri-state) outputs allow multiple devices to share a common bus by high-impedance disconnection when disabled.
Key features include Schmitt-trigger inputs with hysteresis that tolerate slow or noisy input edges typical of automotive harnesses, wide VCC operation of the HCS Schmitt-CMOS family, two independent active-low output-enable pins (OE1 and OE2) for flexible bus control, and a flow-through pinout that simplifies PCB routing by keeping inputs on one side and outputs on the other. The Q1 grade ensures AEC-Q100 qualification and PPAP support for automotive designs.
The HCS (HC with Schmitt input) architecture combines high-speed CMOS output drive with hysteresis-enhanced input stages, improving noise margin on long or filtered signal lines. Outputs are non-inverting, so logic polarity is preserved, making the device suitable for address and control bus buffering in MCU-based systems.
Typical applications include automotive body electronics and ADAS control modules, buffering GPIO or SPI/control lines from MCUs such as the TMS320F2800xx series, industrial PLC I/O isolation, and level-tolerant interfacing to switches and sensors with slow edge rates.
Design tip: tie both OE pins low for always-enabled operation, and keep VCC decoupling (100 nF ceramic) close to the supply pins; the Schmitt inputs allow RC-filtered inputs but do not eliminate the need for controlled signal routing.
Drop-in alternatives for SN74HCS541QPWRQ1 — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with SN74HCS541QPWRQ1 (same form factor and footprint) — differing in Output Enable, Input Type, Output Type, Bits per Element, Function.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
SN74HCS541PWR
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$0.22 / Unit
View Datasheet →SN74LVC244QAPWRQ1
✅ Drop-In✓ In Stock
$0.26 / Unit
View Datasheet →SN74AHC9541-Q1
⚡ Same Package✓ In Stock
Contact for price
View Datasheet →SN74HC541APWR
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
MC74HC541AFL2
⚡ Same Package ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
SN74HCS541QPWRQ1 Maximum Ratings & Electrical Characteristics
| Function | Octal buffer / line driver, non-inverting |
| Bits per Element | 8 |
| Elements | 1 |
| Input Type | Schmitt-Trigger |
| Output Type | 3-State |
| Polarity | Non-Inverting |
| Output Enable | 2 active-low OE pins |
| Family | HCS (HC Schmitt CMOS) |
| Automotive Qualification | AEC-Q100 |
| Operating Temperature | -40C to +125C |
| Package | 20-TSSOP (PW) |
| Mounting Type | Surface Mount |
| Pinout Style | Flow-Through |
| Packaging | Tape & Reel (R) |
| RoHS Status | Compliant |
SN74HCS541QPWRQ1 Pin Configuration
| Pin 1 | OE1 — Output enable 1 (active low) |
| Pin 2 | 1A1 — Input A1, buffer 1 |
| Pin 3 | 1A2 — Input A2, buffer 1 |
| Pin 4 | 1A3 — Input A3, buffer 1 |
| Pin 5 | 1A4 — Input A4, buffer 1 |
| Pin 6 | 2A1 — Input A1, buffer 2 |
| Pin 7 | 2A2 — Input A2, buffer 2 |
| Pin 8 | 2A3 — Input A3, buffer 2 |
| Pin 9 | 2A4 — Input A4, buffer 2 |
| Pin 10 | GND — Ground |
| Pin 11 | 2Y1 — Output Y1, buffer 2 (3-state) |
| Pin 12 | 2Y2 — Output Y2, buffer 2 (3-state) |
| Pin 13 | 2Y3 — Output Y3, buffer 2 (3-state) |
| Pin 14 | 2Y4 — Output Y4, buffer 2 (3-state) |
| Pin 15 | 1Y4 — Output Y4, buffer 1 (3-state) |
| Pin 16 | 1Y3 — Output Y3, buffer 1 (3-state) |
| Pin 17 | 1Y2 — Output Y2, buffer 1 (3-state) |
| Pin 18 | 1Y1 — Output Y1, buffer 1 (3-state) |
| Pin 19 | OE2 — Output enable 2 (active low) |
| Pin 20 | VCC — Supply voltage |
Typical Applications
SN74HCS541QPWRQ1 is suitable for 6 applications: Automotive Body Electronics, MCU Control Bus Buffering, Industrial PLC I/O, Switch and Sensor Interface, LED Display and Driver Enable, Test and Measurement Fixtures.
Automotive Body Electronics
In body control modules, door modules, and lighting controllers, the SN74HCS541QPWRQ1 buffers MCU GPIO to lamp drivers, relays, and switch matrices. Its AEC-Q100 qualification and -40C to +125C rating meet automotive Grade 1 requirements, while Schmitt-trigger inputs reject noise coupled from injectors, motors, and switched loads on harness lines. Placed between the MCU port and fan-out loads, it provides strong CMOS drive and 3-state bus isolation for diagnostics, with the flow-through pinout simplifying routing between the connector side and MCU side of the PCB.
Recommended
MCU Control Bus Buffering
For address, control, and chip-select lines from MCUs such as the TMS320F2800xx series, the SN74HCS541QPWRQ1 fans out drive capability to multiple peripheral ICs without loading the MCU pins. The 3-state outputs let a boot-time supervisor or FPGA share the bus, with OE1/OE2 enabling sequenced bus handoff. The non-inverting buffers preserve logic polarity, and the HCS Schmitt inputs tolerate the slow RC-filtered reset and enable lines commonly found on control boards, reducing false clocking from ground-bounce during switching events.
Recommended
Industrial PLC I/O
In PLC digital input cards, field signals arrive through optocouplers and RC filters that produce slow, noisy edges. The SN74HCS541QPWRQ1 Schmitt-trigger inputs convert these edges into clean logic transitions, while the octal 3-state outputs feed an MCU or backplane bus that multiple cards share. Its -40C to +125C temperature range and tape-and-reel supply support high-volume industrial manufacturing. The flow-through pinout aligns naturally with terminal-block-to-processor signal routing on standard PLC card layouts.
Recommended
Switch and Sensor Interface
Mechanical switches,Hall latches, and analog-comparator outputs frequently generate slow or bouncy edges. The SN74HCS541QPWRQ1 hysteresis specification prevents multiple transitions on such signals, making it suitable as a Schmitt buffer stage before MCU timers or counters. Two active-low enables allow firmware to gate sensor data onto a shared bus only during sampling windows, reducing bus contention. Its AEC-Q100 rating extends this interface architecture from consumer appliances into automotive switch clusters and steering-column modules.
Recommended
LED Display and Driver Enable
In automotive and industrial LED matrices and instrument clusters, the SN74HCS541QPWRQ1 buffers row/column enable and blanking lines from the controller to LED driver ICs. The 3-state outputs allow other controllers to take over display control during diagnostic modes, and the fast CMOS outputs keep enable skew low across eight parallel channels. Its 20-TSSOP footprint fits dense cluster PCBs, and the automotive qualification covers the elevated cabin temperatures near displays and lighting electronics.
Recommended
Test and Measurement Fixtures
Automated test equipment and bench fixtures use the SN74HCS541QPWRQ1 to route control signals to device-under-test sockets without loading the host controller. The 3-state outputs permit safe sharing of test-bus lines between multiple fixture cards, and Schmitt inputs clean up long-cable signals from the test host. Operation to +125C supports burn-in racks, and the widely available 20-TSSOP package simplifies socketed adapter-board designs and quick BOM replenishment across test stations.
Recommended
Recommended Products Summary
Engineering reference data for SN74HCS541QPWRQ1 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | SN74HCS541PWR | SN74LVC244QAPWRQ1 | MC74HC541AFL2 |
|---|---|---|---|---|
| Package | 20-TSSOP (PW) | 20-TSSOP (PW) - same | 20-TSSOP (PW) - same | 20-TSSOP - same footprint, verify datasheet |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | onsemi |
| Automotive AEC-Q100 | Yes (Q1) | No | Yes (Q1) | No |
| Schmitt-Trigger Inputs | Yes | Yes | No | No |
| Channels | 8 (non-inverting) | 8 (non-inverting) | 8 (non-inverting) | 8 (non-inverting) |
| Output Type | 3-State | 3-State | 3-State | 3-State |
| Operating Temperature | -40C to +125C | -40C to +125C | -40C to +125C | -40C to +85C |
| Output Enable Pins | 2 (active-low) | 2 (active-low) | 2 (active-low) | 2 (active-low) |
Key Differentiators
- Schmitt-trigger inputs for noisy/slow edges (vs SN74LVC244QAPWRQ1)
- Automotive qualification at HC price point (vs SN74HCS541PWR)
- Wider VCC range than LVC family (vs SN74LVC244QAPWRQ1)
Design Notes
Place a 100 nF ceramic decoupling capacitor within 3 mm of the VCC (pin 20) and GND (pin 10) pins, with an additional 1 uF bulk capacitor nearby. The flow-through pinout lets you keep input traces on one board side and output traces on the other, minimizing crosstalk between buffered groups. Avoid routing high-dv/dt automotive load lines parallel to the Schmitt inputs.
Both OE1 (pin 1) and OE2 (pin 19) must be low for outputs to drive; leaving either floating causes indeterminate states. Always use pull-up resistors (10k to VCC) on OE lines so outputs default to high-impedance during MCU reset - critical in shared-bus systems to prevent contention during power-up sequencing.
The Schmitt-trigger inputs tolerate slow RC-filtered edges, but hysteresis does not protect against supply-dip-induced misreads. Keep series resistance on input filters modest (1k-10k) so leakage currents do not shift the switching thresholds. Unused inputs should be tied to VCC or GND, never left floating on CMOS logic.
Compliance Information
AEC-Q100 automotive qualified per TI product page. RoHS/lead-free per standard TI Q1 flow; other values not stated in provided data.
