NL27WZ125USG - Dual Buffer, 3-State, US8 | onsemi
MPN: NL27WZ125USG ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $0.2691 | $0.27 |
NL27WZ125USG Overview
Background: A logic buffer (also called a line driver) is a non-inverting digital building block whose primary function is to amplify the current drive of a digital signal without changing its logic level. Buffers sit in the signal path between a low-power source (microcontroller GPIO, ASIC output, or another logic device) and a load that demands more current than the source can supply (long PCB traces, multiple receivers, bus participants, or low-impedance loads). Buffers with 3-state outputs extend this role by adding a high-impedance state, allowing multiple drivers to share a common bus (bus arbitration) without contention. The NL27WZ125USG is a dual buffer (two buffers in one package) with 3-state outputs, occupying the mid-position in the logic hierarchy: gate -> buffer/inverter -> flip-flop -> complex function.
Key features include 24 mA balanced output drive, LVTTL/LVCMOS compatibility with 5 V TTL when VCC = 3 V, near-zero static supply current, and very low quiescent supply current. The 3-state OE input is active-low (logic 0 enables the output, logic 1 places it in high-impedance). The US8 package offers an extremely small footprint ideal for portable and space-constrained applications, and the device is specified over the -40C to +85C commercial operating temperature range.
The NL27WZ125USG is pin-compatible with and serves as a direct replacement for the industry-standard NC7WZ125, allowing drop-in substitution in legacy designs. The CMOS architecture delivers low power consumption, low propagation delay (typically a few nanoseconds at 5 V), and minimal signal degradation.
Typical applications include bus interface buffering, signal isolation, level shifting between logic domains (with external pass elements), LED driver control, and general-purpose logic interfacing in portable electronics, IoT devices, and consumer products.
When designing with this part, observe input rise/fall time limits to avoid excessive supply current, and ensure the OE pin is never left floating (tie to GND through a resistor or to VCC to define the default state). Decouple VCC with a 0.1 uF ceramic capacitor placed close to the supply pin.
This page synthesizes distributor pricing, drop-in pin-compatible alternatives, and practical design notes that complement the manufacturer datasheet.
Drop-in alternatives for NL27WZ125USG — 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 NL27WZ125USG (same form factor and footprint) — differing in Operating Temperature, Output Enable, Package, RoHS Status.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
NL27WZ125US
✅ Drop-In📋 Reference alternative (not in catalog)
NL27WZ125USG-Q
✅ Drop-In📋 Reference alternative (not in catalog)
NC7WZ125P6X
✅ Drop-In📋 Reference alternative (not in catalog)
NL27WZ126USG
✅ Drop-In📋 Reference alternative (not in catalog)
SN74LVC2G125DCUR
✅ Drop-In✓ In Stock
$0.14 / Unit
View Datasheet →MC74VHC1G125DFT1G
✅ Drop-In📋 Reference alternative (not in catalog)
NL27WZ125USG Maximum Ratings & Electrical Characteristics
| Function | Dual Buffer, Non-Inverting |
| Number of Elements | 2 |
| Bits per Element | 1 |
| Output Type | 3-State |
| Logic Family | VHC / CMOS |
| Supply Voltage (VCC) | 1.65 V to 5.5 V |
| Output Drive (IOH/IOL) | ±24 mA (balanced at VCC = 3 V) |
| Output Enable | Active-Low (per channel) |
| Static Supply Current | Near-zero (sub-uA) |
| Input Compatibility | LVCMOS, LVTTL (5 V TTL with VCC = 3 V) |
| Operating Temperature | -40C to +85C |
| Package | US8 (MicroPak, 8-pin) |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant (Pb-Free) |
| Lead-Free | Yes |
| Pin Count | 8 |
NL27WZ125USG Pin Configuration
| Pin 1 | OE1 — Output Enable for channel 1 (active-low) |
| Pin 2 | A1 — Input for channel 1 |
| Pin 3 | GND — Ground reference |
| Pin 4 | Y1 — Output for channel 1 (3-state) |
| Pin 5 | VCC — Positive supply (1.65 V to 5.5 V) |
| Pin 6 | Y2 — Output for channel 2 (3-state) |
| Pin 7 | A2 — Input for channel 2 |
| Pin 8 | OE2 — Output Enable for channel 2 (active-low) |
Typical Applications
NL27WZ125USG is suitable for 6 applications: Bus Interface Buffer, Signal Isolation, Logic Level Translation, LED Driver Control, Memory Address/Data Buffer, Portable Consumer Electronics.
Bus Interface Buffer
The NL27WZ125USG provides ±24 mA balanced drive with 3-state outputs for shared bus applications, making it ideal for microcontroller GPIO expansion to multi-device buses. Each buffer has an independent active-low output enable pin, allowing multiple NL27WZ125USG devices to share a common bus line with proper OE sequencing to prevent contention. The 1.65 V to 5.5 V supply range lets it bridge 1.8 V MCUs and 5 V peripherals without level shifters. Compared to discrete pull-ups, this buffer reduces power consumption and improves signal integrity on heavily loaded traces.
Recommended
Signal Isolation
Use the NL27WZ125USG to break ground loops and isolate sensitive analog/digital domains on mixed-signal PCBs. The buffer's near-zero static supply current and small US8 footprint allow point-of-use isolation without significant power or board area penalty. The 24 mA drive isolates long trace runs from high-impedance sources, reducing EMI pickup and improving noise immunity. This is particularly valuable in audio, sensor, and instrumentation designs where digital switching noise must be kept away from analog signal paths. Pair it with bulk decoupling for clean rail delivery to the buffer.
Recommended
Logic Level Translation
The NL27WZ125USG supports voltage domain translation between 1.8 V, 2.5 V, 3.3 V, and 5 V logic levels within its 1.65 V to 5.5 V VCC range. The TTL-compatible inputs accept 5 V signals when VCC = 3 V (per the onsemi datasheet's LVTTL compatibility specification), simplifying mixed-voltage interfacing. The 24 mA output drive ensures clean edges on level-translated signals driving multiple loads or long cables. This application is common in portable electronics where the MCU runs at 1.8 V but peripheral modules operate at 3.3 V or 5 V.
Recommended
LED Driver Control
The NL27WZ125USG can directly drive small-signal LEDs and LED-driver logic inputs thanks to its ±24 mA balanced output drive. Connect a buffer output to the gate of an external MOSFET or directly to a low-current LED via a current-limiting resistor. The 3-state OE pin allows PWM brightness control by toggling enable at audio or sub-audio frequencies without burdening the MCU timer. The US8 package fits easily in handheld consumer products where board space is at a premium. The low quiescent current makes this an efficient choice for battery-powered indicator designs.
Recommended
Memory Address/Data Buffer
Use the NL27WZ125USG as an address or data line buffer in memory subsystems where fan-out exceeds the MCU's GPIO drive capability. The 24 mA drive and 3-state output cleanly multiplex address lines between memory banks or peripheral devices. The buffer's low propagation delay adds only a few nanoseconds to memory access time, negligible for most embedded applications. The US8 footprint saves board space versus larger SOIC-8 buffers, enabling compact designs for IoT endpoints, wearables, and embedded modules.
Recommended
Portable Consumer Electronics
The NL27WZ125USG excels in portable consumer products due to its tiny US8 footprint, 1.65 V to 5.5 V supply range, and near-zero static supply current. Smart watches, fitness bands, earbuds, and remote controls benefit from its ability to buffer low-power MCU signals to higher-current peripherals without draining the battery. The buffer's wide voltage tolerance supports single-cell Li-ion (3.0 V to 4.2 V) and coin-cell applications. The CMOS low-power design keeps standby consumption negligible even when permanently enabled in always-on devices.
Recommended
Recommended Products Summary
Engineering reference data for NL27WZ125USG — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | NL27WZ125US | NL27WZ125USG-Q | NC7WZ125P6X | SN74LVC2G125DCUR | MC74VHC1G125DFT1G |
|---|---|---|---|---|---|---|
| Brand | onsemi | onsemi | onsemi | onsemi (Fairchild legacy) | Texas Instruments | onsemi |
| Package | US8 (MicroPak, 8-pin) | US8 - same | US8 - same | SC-88 (US8-equivalent) | US8 (VSSOP-8) - same | US8 (SOT-353) - same |
| Channels | 2 (dual) | 2 (dual) | 2 (dual) | 2 (dual) | 2 (dual) | 1 (single) |
| Output Type | 3-State | 3-State | 3-State | 3-State | 3-State | 3-State |
| Output Enable Polarity | Active-Low | Active-Low | Active-Low | Active-Low | Active-Low | Active-Low |
| Supply Voltage Range | 1.65 V to 5.5 V | 1.65 V to 5.5 V | 1.65 V to 5.5 V | 1.65 V to 5.5 V | 1.65 V to 5.5 V | 2.0 V to 5.5 V |
| Output Drive (mA) | ±24 mA | ±24 mA | ±24 mA | ±24 mA | ±24 mA | ±8 mA |
| Automotive Grade (AEC-Q100) | No | No | Yes | No | No | No |
| Logic Family | VHC (CMOS) | VHC (CMOS) | VHC (CMOS) | TinyLogic (CMOS) | LVC (CMOS) | VHC (CMOS) |
Key Differentiators
- Direct NC7WZ125 replacement in identical US8 footprint (vs NC7WZ125P6X)
- Wide 1.65 V to 5.5 V supply supports more applications than 2.0 V minimum parts (vs MC74VHC1G125DFT1G)
- Higher ±24 mA drive vs ±8 mA single-channel alternative (vs MC74VHC1G125DFT1G)
- Automotive-qualified variant available (NL27WZ125USG-Q) (vs SN74LVC2G125DCUR)
Design Notes
Never leave the OE pin unconnected - a floating OE can drift into the threshold region, causing the output to oscillate between high-impedance and driven states. Always tie OE LOW (GND) to keep the buffer permanently enabled, or HIGH (VCC) to keep it disabled, ideally through a 10 kOhm resistor. Also ensure input rise/fall times are faster than the datasheet limit (typically < 20 ns/V) to avoid excessive dynamic supply current from the CMOS input stage. Slow edges cause the input buffer to draw shoot-through current for the transition window.
Place a 0.1 uF ceramic decoupling capacitor as close as physically possible to the VCC pin (pin 5) and a parallel 1 uF or 10 uF bulk capacitor on the supply rail near the device. For high-frequency bus signaling, add a ferrite bead between the buffer VCC and the digital supply to prevent buffer switching noise from coupling back into sensitive analog rails. The NL27WZ125USG's near-zero static supply current means total current draw is dominated by load capacitance charging (C*V*F), so bus frequency and load capacitance directly control total power.
Route the input traces (A1, A2) and output traces (Y1, Y2) with short, direct paths and avoid running them parallel to switching signals for more than a few millimeters to minimize crosstalk. Place the device near the bus midpoint when driving long traces to balance source and load impedances. The US8 package's exposed diepad (where present in the US8 family) should be soldered to a copper pad to improve thermal dissipation, although the NL27WZ125USG's low power dissipation rarely requires thermal management.
The NL27WZ125USG is suitable for moderate-speed digital signals (up to ~100 MHz typical) but is not optimized for high-speed buses like DDR memory or gigabit serial interfaces. For bus speeds above 50 MHz, calculate the trace propagation delay vs. signal rise time - if rise time < 2x propagation delay, controlled impedance and termination become necessary. The ±24 mA output drive can source significant current, but heavily loaded or long buses may still require additional series damping resistors (22-33 ohm) to suppress ringing.
Compliance Information
Standard NL27WZ125USG is Pb-Free per onsemi datasheet. For AEC-Q100 automotive applications, use the NL27WZ125USG-Q variant. Halogen-free status not explicitly stated in provided data - marked as unknown per data authenticity rules.
