Texas Instruments CD4068BM

Overview

CD4068BM from Texas Instruments is an 8-input NAND gate CMOS logic IC in a 14-pin SOIC package, operating across -55°C to +125°C, with typical propagation delay of 90 ns at 5 V and supply current of 20 µA at 10 V. It serves as a high-noise-immunity combinational logic element in industrial control timing circuits and sensor interface signal conditioning.

For engineers reviewing the CD4068BM datasheet, CD4068BM pinout, CD4068BM application, or CD4068BM equivalent, key selection considerations include its wide temperature range, low static power consumption, dual-supply compatibility (3–18 V), and compatibility with legacy CD4000-series logic families in mixed-voltage system designs.

Technical Context

The CD4068BM implements a single 8-input NAND function using standard CMOS transistor pairs, with symmetrical input thresholds at 50% V_DD and rail-to-rail output swing. Its architecture supports direct interfacing with TTL, NMOS, and other CMOS families without level-shifting.

All eight inputs are fully buffered and electrically identical, with no internal fan-in hierarchy or cascaded gates-each input drives the same NAND core directly. The device exhibits no internal latching, clocking, or state retention; it operates strictly as a combinatorial logic gate with no setup/hold timing requirements.

Key Specifications

Pinout & Package

CD4068BM is housed in a 14-lead SOIC (D) package, 3.9 mm wide, 8.75 mm long, and 1.75 mm maximum height, compliant with JEDEC MS-012 variation AB and RoHS-compliant NIPDAU lead finish.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 8-input NAND gate applications.

Compared with CD4068BM, CD4068BM96.A offers identical functionality with optimized packaging for volume SMT, while CD4068BNSR provides the same logic in a wider SOP package requiring layout revision - neither is pin-compatible without footprint adaptation.

Availability

CD4068BM is available at Aetrix Electronics and suitable for industrial sequence control, multi-sensor alarm aggregation, and programmable logic interface applications requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for CD4068BM 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

Texas Instruments is a global semiconductor company founded in 1930, specializing in analog, embedded processing, and logic ICs with broad industrial and automotive qualification.

The CD4068BM belongs to TI's legacy CD4000B series of radiation-tolerant, wide-voltage CMOS logic devices, designed for reliability-critical applications where long-term stability and temperature resilience outweigh speed requirements.

FAQ

What is the maximum operating frequency of the CD4068BM?

The CD4068BM is not characterized for maximum clock frequency due to its combinatorial nature. Its usable toggle rate depends on propagation delay (90 ns max at 5 V) and load capacitance. For a 50 pF load, the practical limit is approximately 5 MHz under worst-case conditions. The CD4068BM does not include internal clock circuitry or synchronous elements, so frequency limits derive solely from RC time constants in the application layout.

Can CD4068BM drive TTL loads directly?

Yes, the CD4068BM can drive standard TTL loads directly when operated at V_DD ≥ 4.5 V. At 5 V supply, its output sink current (I_OL) exceeds 4 mA, satisfying the 1.6 mA requirement for one TTL unit load. However, fan-out is limited to ~2 LS-TTL loads at 15 V due to reduced voltage margin; verify logic thresholds in your specific V_DD and temperature conditions using the CD4068BM datasheet graphs.

Is CD4068BM pin-compatible with CD4068BE (PDIP) or CD4068BF (CDIP)?

Yes, CD4068BM is functionally and pinout-compatible with CD4068BE and CD4068BF - all share identical 14-pin numbering: inputs on pins 1–6, 8–9; GND on pin 7; output on pin 10; V_DD on pin 14. Mechanical differences exist (SOIC vs. PDIP/CDIP), but the CD4068BM pin mapping matches the industry-standard 4000-series logic layout, enabling direct PCB footprint substitution where package height and thermal constraints allow.

Does CD4068BM support mixed-voltage operation (e.g., 3.3 V inputs with 12 V V_DD)?

No, CD4068BM does not support true mixed-voltage operation. Its input thresholds scale with V_DD (V_IL/V_IH ≈ 0.5 × V_DD), so 3.3 V inputs applied to a 12 V-powered CD4068BM will register as logic low. To interface lower-voltage signals, use resistive dividers or dedicated level translators - the CD4068BM itself requires input voltages referenced to its own V_DD.

What is the MSL rating and reflow profile for CD4068BM?

The CD4068BM carries an MSL Level-1 rating with unlimited floor life and a peak reflow temperature of 260°C. This applies to both CD4068BM and CD4068BM96.A variants. Reflow must follow JEDEC J-STD-020 guidelines for Level-1 components, with ramp rates ≤ 3°C/s and time above 217°C limited to 60–150 seconds. No pre-baking is required prior to reflow soldering.