Nexperia USA Inc. HEF4049BT,653

Overview

HEF4049BT,653 from Nexperia is a hex CMOS inverting buffer with overvoltage-tolerant inputs rated to 15.0 V, enabling HIGH-to-LOW level shifting between logic families. It operates across 3.0 V to 15.0 V supply, delivers ±24 mA sink/source drive at 15 V, and features symmetrical output characteristics for TTL/DTL interfacing in industrial control and legacy system upgrades.

For engineers reviewing the HEF4049BT,653 datasheet, HEF4049BT,653 pinout, HEF4049BT,653 application, or HEF4049BT,653 equivalent, this device is selected for robust level translation, high-noise immunity in mixed-voltage systems, and direct drive of two standard TTL loads without external buffering.

Technical Context

The HEF4049BT,653 implements six independent CMOS inverter stages with input clamping diodes enabling 15.0 V overvoltage tolerance while powered from as low as 3.0 V. Its static operation supports zero-static-current latching and eliminates dynamic power concerns in low-frequency control paths.

Each inverter exhibits matched VOH/VOL (≤0.05 V low-level, ≥14.95 V high-level at 15 V), guaranteed fan-out of 16 for 74L and 2 for standard TTL, and propagation delays ranging from 12 ns (15 V, CL = 50 pF) to 70 ns (5 V, CL = 50 pF), supporting both legacy and modern timing budgets.

Key Specifications

Pinout & Package

HEF4049BT,653 is housed in a plastic SO16 (SOT109-1) package: 16-pin small outline, 3.9 mm body width, gull-wing leads, JEDEC MS-012 compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar hex inverting buffer applications.

Compared with CD4049UBE and 74HC4049PW, the HEF4049BT,653 uniquely supports true 15 V input tolerance at any VDD ≥3 V, making it the only drop-in solution for mixed-voltage level translation without redesign.

Availability

HEF4049BT,653 is available at Aetrix Electronics and suitable for industrial control panels, legacy system upgrades, mixed-voltage sensor interfaces, and embedded instrumentation requiring stable component supply across extended temperature and voltage ranges.

Supply support for HEF4049BT,653 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

Nexperia is a global semiconductor expert specializing in high-performance, reliable standard logic and power devices, with manufacturing rooted in process innovation and automotive-grade quality systems.

The HEF4049BT,653 belongs to Nexperia's legacy-compatible CMOS logic family, engineered for backward compatibility with 4000-series designs while adding robustness for modern industrial voltage interoperability.

FAQ

Can HEF4049BT,653 operate with VDD = 3.3 V and accept 5 V inputs?

Yes. The device supports VDD from 3.0 V to 15.0 V and tolerates input voltages up to 15.0 V regardless of supply level. At VDD = 3.3 V, inputs up to 5 V are safely clamped and translated to valid LOW/HIGH outputs meeting 3.3 V logic thresholds (VIH = 2.3 V min, VIL = 1.0 V max).

What is the maximum capacitive load each output can drive reliably?

Each output is characterized up to 50 pF load capacitance per the datasheet's dynamic test conditions. For reliable operation beyond 50 pF, propagation delay increases linearly (e.g., tPHL ≈ 9 ns + 0.05 ns/pF × CL at 15 V); keep total load ≤100 pF to maintain <25 ns delay and avoid excessive transition time degradation.

Are pins 13 and 16 internally connected or truly isolated?

Pins 13 and 16 are explicitly designated "n.c." (not connected) in the official Nexperia datasheet and functional diagram. They are electrically isolated from all internal circuitry and must remain unconnected or tied to ground per PCB layout guidelines - no internal bonding or parasitic coupling exists.

Does HEF4049BT,653 require external pull-up or pull-down resistors on unused inputs?

No. Unused inputs should be tied to VDD or VSS to prevent floating states and minimize supply current. The device has no internal pull-ups; leaving inputs unconnected risks oscillation, increased IDD, and ESD susceptibility due to unterminated CMOS gates.