TLC556IN Equivalent & Substitute Parts

Part Overview

The TLC556IN is a dual timer/oscillator integrated circuit manufactured by Texas Instruments, classified as a 555-type timing device. This component operates at a maximum frequency of 2.1MHz and is housed in a 14-pin DIP package suitable for through-hole mounting applications. The device is currently in active production status and maintains full RoHS3 compliance.

Substitute parts become necessary when the primary component experiences supply constraints, extended lead times, or when design requirements permit operation within the electrical and mechanical tolerances of alternative qualified devices. The TLC556IN can be substituted with functionally equivalent dual timer ICs that share the same package configuration and core 555-type architecture.

Substiute Parts

TLC556IN

Texas InstrumentsIn Stock: 2159TLC556IN Datasheet

Current PartRFQ

ICM7556IPD+

Analog Devices Inc./Maxim IntegratedIn Stock: 1358ICM7556IPD+ Datasheet

MFR RecommendedRFQ

ICM7556IPDZ

Renesas Electronics CorporationIn Stock: 3634ICM7556IPDZ Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the TLC556IN is determined by the following mandatory criteria:

Package Compatibility: All substitute parts must use the 14-DIP (0.300", 7.62mm) package configuration with through-hole mounting to ensure direct PCB compatibility without layout modifications.

Functional Type: All candidates must be 555-type dual timer/oscillator devices to maintain circuit functionality and pin-level compatibility.

Electrical Operating Range: Substitute parts must support supply voltage ranges that encompass or exceed the TLC556IN operating window of 3V to 15V. Operating temperature ranges must be compatible with the application's thermal requirements.

Frequency Capability: The substitute device's maximum frequency rating must meet or exceed the application's timing requirements. The TLC556IN operates at 2.1MHz; substitute parts with lower frequency ratings may be used only if the application does not require operation above that substitute's maximum frequency specification.

Compliance Status: All substitute parts must maintain RoHS3 compliance and REACH unaffected status to satisfy regulatory requirements equivalent to the primary device.

Parameter Comparison

Engineering Selection Recommendations

ICM7556IPD+ (Analog Devices Inc./Maxim Integrated): This device maintains active product status and provides the widest supply voltage range (3V to 16.5V), which encompasses the TLC556IN operating window. The lower maximum frequency of 500kHz restricts this substitute to applications where timing requirements do not exceed this specification. The significantly reduced supply current (60 µA versus 720 µA) offers power consumption advantages in battery-powered or low-power applications. This part is suitable for direct substitution in designs where the 500kHz frequency ceiling is acceptable.

ICM7556IPDZ (Renesas Electronics Corporation): This device carries obsolete product status, indicating discontinued manufacturing and potential future supply unavailability. While the 1MHz frequency rating and extended supply voltage range (2V to 18V) provide broader operational flexibility than the ICM7556IPD+, the obsolete classification makes this option unsuitable for new designs or long-term production requirements. This part may only be considered for legacy system maintenance where existing inventory is available.

For new designs and ongoing production, the ICM7556IPD+ is the preferred substitute when frequency requirements permit operation at or below 500kHz. The TLC556IN should remain the primary selection for applications requiring the full 2.1MHz frequency capability.

Frequently Asked Questions (FAQ)

Q: Can the ICM7556IPD+ be used as a direct replacement for the TLC556IN in all applications?

A: Direct substitution is possible only if the application's timing frequency requirements do not exceed 500kHz. The ICM7556IPD+ has a maximum frequency rating of 500kHz, compared to the TLC556IN's 2.1MHz capability. If the circuit requires operation above 500kHz, this substitute is not compatible. Both devices share identical 14-DIP package dimensions and pin configurations, ensuring mechanical and electrical interface compatibility within the frequency constraint.

Q: Why is the ICM7556IPDZ listed as a substitute if it is obsolete?

A: The ICM7556IPDZ is included in the substitute list based on historical cross-reference data and may be available through existing inventory channels. However, its obsolete status means manufacturing has been discontinued. This part should not be selected for new designs or applications requiring long-term component availability. It is listed for reference only in cases where legacy system maintenance requires identification of previously used alternatives.

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

A: The TLC556IN draws 720 µA under typical operating conditions, while the ICM7556IPD+ draws only 60 µA and the ICM7556IPDZ draws 120 µA. These differences reflect different circuit design approaches and manufacturing processes. For applications with strict power consumption budgets, the ICM7556IPD+ offers significant advantages. However, this lower current consumption does not affect functional compatibility; it represents an efficiency improvement in the substitute devices.

Q: Are all three devices RoHS3 compliant?

A: Yes, all three devices—TLC556IN, ICM7556IPD+, and ICM7556IPDZ—maintain RoHS3 compliance and REACH unaffected status. This ensures regulatory equivalence across all three options for applications subject to environmental compliance requirements.

Q: What is the significance of the operating temperature range differences?

A: The TLC556IN operates from -40°C to 85°C, providing the widest temperature range. The ICM7556IPD+ operates from -20°C to 85°C, and the ICM7556IPDZ from -25°C to 85°C. For applications requiring operation below -25°C, only the TLC556IN is suitable. For standard industrial and commercial temperature ranges (-20°C to 85°C or warmer), all three devices are compatible. Application thermal requirements must be verified before selecting a substitute.