KA555 Equivalent & Substitute Parts

Part Overview

The KA555 is a 555 Type Timer/Oscillator (Single) IC manufactured by onsemi in 8-DIP packaging. This component is classified as obsolete, making equivalent and substitute parts necessary for ongoing design support and procurement. The KA555 operates within a supply voltage range of 4.5V to 16V with a maximum supply current of 7.5 mA and an operating temperature range of 0°C to 70°C. Identifying compatible alternatives ensures design continuity and component availability for applications requiring timer and oscillator functionality.

Substiute Parts

KA555

onsemiIn Stock: 1281KA555 Datasheet

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NA555P

Texas InstrumentsIn Stock: 1619NA555P Datasheet

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SA555P

Texas InstrumentsIn Stock: 47037SA555P Datasheet

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LM555CN/NOPB

Texas InstrumentsIn Stock: 2247LM555CN/NOPB Datasheet

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LMC555CN/NOPB

Texas InstrumentsIn Stock: 3101LMC555CN/NOPB Datasheet

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NE555P

Texas InstrumentsIn Stock: 156362NE555P Datasheet

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SE555P

Texas InstrumentsIn Stock: 8748SE555P Datasheet

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TLC555CP

Texas InstrumentsIn Stock: 20432TLC555CP Datasheet

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TLC555IP

Texas InstrumentsIn Stock: 18103TLC555IP Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the KA555 are grouped based on strict electrical and mechanical compatibility criteria. The primary substitution parameters are:

Critical Compatibility Parameters:

• Package / Case: 8-DIP (0.300", 7.62mm) — all substitutes maintain identical physical form factor
• Mounting Type: Through Hole — all substitutes use through-hole mounting
• Type: 555 Type, Timer/Oscillator (Single) — functional equivalence maintained across all alternatives
• Voltage - Supply Range: Must encompass or overlap with 4.5V ~ 16V
• Operating Temperature Range: Must support minimum 0°C ~ 70°C operation

Upgrade Parts (NA555P, SA555P) represent active, higher-specification alternatives with extended temperature ranges and RoHS3 compliance, suitable for direct replacement with enhanced reliability.

Similar Parts (LM555CN/NOPB, LMC555CN/NOPB, NE555P, SE555P, TLC555CP, TLC555IP) provide functional equivalence with variations in frequency capability, supply current, and temperature performance. Selection depends on specific application requirements within the defined parameter ranges.

Parameter Comparison

Engineering Selection Recommendations

For Direct Replacement with Enhanced Specifications: NA555P and SA555P are active Texas Instruments products with ROHS3 compliance. Both maintain the 4.5V ~ 16V supply voltage range and 8-DIP package of the KA555. NA555P extends the operating temperature to -40°C ~ 105°C, while SA555P operates to -40°C ~ 85°C. Both are suitable for applications requiring improved temperature performance and regulatory compliance.

For Standard Operating Conditions (0°C ~ 70°C): LM555CN/NOPB and NE555P provide direct functional equivalence with identical electrical specifications to the KA555 within the standard temperature range. Both are active products with ROHS3 compliance and 100kHz frequency capability.

For Extended Temperature Range Applications: SE555P operates across -55°C ~ 125°C with supply voltage range of 4.5V ~ 18V, providing the widest temperature coverage among available substitutes. This part is suitable for industrial and automotive applications requiring extreme temperature performance.

For Low-Power Applications: LMC555CN/NOPB and TLC555IP offer significantly reduced supply current (150 µA and 360 µA respectively) compared to the KA555 (7.5 mA). LMC555CN/NOPB operates at 1.5V ~ 15V with 3MHz frequency capability, while TLC555IP operates at 3V ~ 15V with 2.1MHz frequency. Both are suitable for battery-powered and low-power timer applications.

For High-Frequency Applications: LMC555CN/NOPB (3MHz) and TLC555CP/TLC555IP (2.1MHz) provide higher frequency operation than standard 555 variants, enabling faster timing and oscillation applications.

All substitute parts maintain the 8-DIP through-hole package form factor, ensuring mechanical compatibility with existing PCB designs.

Frequently Asked Questions (FAQ)

Q: Can I use NA555P or SA555P as a direct replacement for KA555? A: Yes. Both NA555P and SA555P maintain the identical 8-DIP package, 4.5V ~ 16V supply voltage range, and 555 Type timer/oscillator functionality. Both are active products with ROHS3 compliance, making them suitable direct replacements with improved temperature performance and regulatory compliance.

Q: What is the difference between NE555P and LM555CN/NOPB? A: Both parts are functionally equivalent with identical electrical specifications (4.5V ~ 16V supply, 10 mA current, 100kHz frequency, 0°C ~ 70°C operating temperature) and 8-DIP packaging. The primary difference is manufacturer designation and part numbering convention. Both are active Texas Instruments products with ROHS3 compliance.

Q: Which substitute should I use for low-power applications? A: LMC555CN/NOPB and TLC555IP are optimized for low-power operation with supply currents of 150 µA and 360 µA respectively, compared to 7.5 mA for the KA555. LMC555CN/NOPB operates at 1.5V ~ 15V with 3MHz capability, while TLC555IP operates at 3V ~ 15V with 2.1MHz capability. Selection depends on your specific voltage and frequency requirements.

Q: Are all substitute parts RoHS compliant? A: All substitute parts listed are ROHS3 compliant. The original KA555 does not specify RoHS status. If RoHS compliance is required for your application, all listed substitutes meet this requirement.

Q: Can I use SE555P in place of KA555? A: Yes. SE555P maintains the 8-DIP package and 555 Type functionality. It operates at 4.5V ~ 18V (slightly higher upper limit than KA555's 16V) and -55°C ~ 125°C (extended temperature range). SE555P is suitable for applications requiring extreme temperature performance and is ROHS3 compliant.

Q: What is the difference between TLC555CP and TLC555IP? A: Both are LinCMOS™ series parts with identical 2.1MHz frequency and 8-DIP packaging. TLC555CP operates at 0°C ~ 70°C with 2V ~ 15V supply voltage, while TLC555IP operates at -40°C ~ 85°C with 3V ~ 15V supply voltage. TLC555IP is suitable for extended temperature and higher minimum voltage applications.

Q: Will higher supply current in substitute parts affect my circuit design? A: Substitute parts specify maximum supply current ratings. The KA555 specifies 7.5 mA, while most substitutes specify 10 mA. Actual current consumption depends on circuit configuration and operating conditions. Ensure your power supply can deliver the specified maximum current for the selected substitute part.

Q: Can I use LMC555CN/NOPB in a circuit designed for standard 555 operation? A: LMC555CN/NOPB is functionally compatible but operates at lower supply voltage (1.5V minimum vs. 4.5V for KA555) and lower supply current (150 µA vs. 7.5 mA). It is suitable for circuits operating within its 1.5V ~ 15V range. Verify your circuit design operates within these parameters before substitution.