SN74LS76ADR Equivalent & Substitute Parts

Part Overview

The SN74LS76ADR is a dual JK-type flip-flop logic integrated circuit manufactured by Texas Instruments in the 74LS series. This component features two independent 1-bit JK flip-flops with complementary outputs, set/preset and reset functions, and negative edge triggering. The device is classified as obsolete, making identification of functionally compatible alternatives essential for ongoing system support and component procurement.

Substiute Parts

SN74LS76ADR

Texas InstrumentsIn Stock: 973SN74LS76ADR Datasheet

Current PartRFQ

SN74LS109ADR

Texas InstrumentsIn Stock: 3365SN74LS109ADR Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution compatibility for the SN74LS76ADR is determined by the following critical parameters:

• Package / Case: 16-SOIC (0.154", 3.90mm Width) — mechanical and electrical interface compatibility
• Series: 74LS — logic family and voltage specifications
• Type: JK Type Flip-Flop — functional logic configuration
• Number of Elements: 2 — quantity of independent flip-flops
• Number of Bits per Element: 1 — bit width per element
• Output Type: Complementary — Q and Q̄ output availability
• Voltage - Supply: 4.75V ~ 5.25V — power supply compatibility
• Operating Temperature: 0°C ~ 70°C (TA) — thermal operating range
• Function: Set(Preset) and Reset — control functionality

The SN74LS109ADR is identified as a direct substitute based on matching package, series, element count, bit width, output type, supply voltage, and operating temperature range. Both devices are 16-SOIC surface-mount components within the 74LS logic family with dual 1-bit JK flip-flops and complementary outputs.

Parameter Comparison

Engineering Selection Recommendations

The SN74LS109ADR is available as an active product from Texas Instruments, whereas the SN74LS76ADR is obsolete. Both devices maintain ROHS3 compliance and unlimited moisture sensitivity rating (MSL 1), ensuring equivalent environmental and regulatory compatibility.

The primary distinction between these components is the trigger type: the SN74LS76ADR operates on negative edge triggering, while the SN74LS109ADR operates on positive edge triggering. This difference affects clock signal timing in sequential logic circuits. Additionally, the SN74LS109ADR exhibits higher propagation delay (40 ns versus 20 ns) and higher quiescent current (8 mA versus 4 mA).

Selection between these devices depends on circuit timing requirements and clock signal polarity. The SN74LS109ADR's active product status provides superior long-term availability and supply chain continuity compared to the obsolete SN74LS76ADR.

Frequently Asked Questions (FAQ)

Q: Can the SN74LS109ADR directly replace the SN74LS76ADR in existing designs?

A: Physical and electrical interface compatibility is confirmed through matching 16-SOIC package, 4.75V–5.25V supply voltage range, and identical output current specifications. However, the positive edge triggering of the SN74LS109ADR differs from the negative edge triggering of the SN74LS76ADR. Circuit redesign or clock signal inversion may be required depending on timing requirements.

Q: What are the key differences in performance between these devices?

A: The SN74LS76ADR operates at 45 MHz maximum clock frequency with 20 ns propagation delay and 4 mA quiescent current. The SN74LS109ADR operates at 33 MHz maximum clock frequency with 40 ns propagation delay and 8 mA quiescent current. These differences may impact system timing margins and power consumption.

Q: Are both devices compliant with current environmental standards?

A: Both the SN74LS76ADR and SN74LS109ADR are ROHS3 compliant with MSL 1 (unlimited moisture sensitivity), confirming equivalent environmental and regulatory compatibility.

Q: Why is the SN74LS76ADR listed as obsolete?

A: The SN74LS76ADR is classified as obsolete by Texas Instruments. The SN74LS109ADR maintains active product status, providing ongoing manufacturing support and supply availability.

Q: Are there packaging options available for the SN74LS109ADR?

A: The SN74LS109ADR is available in Tape & Reel (TR) packaging. Both devices utilize the 16-SOIC (0.154", 3.90mm Width) surface-mount package.