TLC552CD Equivalent & Substitute Parts

Part Overview

The TLC552CD is a dual timer/oscillator IC manufactured by Texas Instruments, classified as a 555-type timing circuit. This component operates at 2.8MHz and is housed in a 14-SOIC surface mount package. The TLC552CD is currently in Last Time Buy status, indicating that Texas Instruments has discontinued or will discontinue production. This necessitates identification of functionally equivalent substitute components to maintain design continuity and ensure long-term component availability for new production runs and field replacements.

Substiute Parts

TLC552CD

Texas InstrumentsIn Stock: 1168TLC552CD Datasheet

Current PartRFQ

TLC556CDR

Texas InstrumentsIn Stock: 32720TLC556CDR Datasheet

MFR RecommendedRFQ

ICM7556ISD+

Analog Devices Inc./Maxim IntegratedIn Stock: 2740ICM7556ISD+ Datasheet

MFR RecommendedRFQ

ICM7556ISD+T

Analog Devices Inc./Maxim IntegratedIn Stock: 1428ICM7556ISD+T Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the TLC552CD is determined by the following critical parameters:

• Package Compatibility: All substitute parts must use the 14-SOIC (0.154", 3.90mm Width) surface mount package to ensure PCB footprint compatibility without redesign.
• Functional Type: All parts must be 555-type dual timer/oscillator ICs to maintain functional equivalence.
• Voltage Supply Range: Substitute parts must support the operating voltage range of the application. The TLC552CD operates from 1V to 18V; substitutes with narrower ranges (such as 2V ~ 15V or 2V ~ 16.5V) are acceptable if the application voltage falls within the substitute's range.
• Operating Temperature Range: The TLC552CD operates from 0°C to 70°C. Substitutes with extended temperature ranges (such as -20°C to 85°C) provide broader operational capability and are acceptable.
• Compliance: All substitute parts must maintain ROHS3 compliance and MSL Level 1 rating to meet regulatory and manufacturing requirements.

Frequency differences among 555-type timer ICs do not preclude substitution, as frequency is determined by external timing components (resistors and capacitors) in the application circuit, not solely by the IC itself.

Parameter Comparison

Engineering Selection Recommendations

TLC556CDR (Texas Instruments, Active Status): This part is the direct Texas Instruments successor within the LinCMOS™ series. It maintains identical package, mounting type, and temperature range specifications. The TLC556CDR operates at 2.1MHz with a supply voltage range of 2V ~ 15V and reduced supply current of 720 µA. Selection of this part preserves single-manufacturer sourcing and maintains design continuity within the Texas Instruments product line. This part is recommended for applications where the supply voltage remains within the 2V ~ 15V range.

ICM7556ISD+ and ICM7556ISD+T (Analog Devices Inc./Maxim Integrated, Active Status): Both variants are functionally equivalent 555-type dual timer ICs from Analog Devices Inc./Maxim Integrated. These parts operate at 500kHz with a supply voltage range of 2V ~ 16.5V and significantly reduced supply current of 60 µA. The extended operating temperature range of -20°C ~ 85°C provides broader environmental capability compared to the TLC552CD. The ICM7556ISD+ is supplied in Tube packaging, while the ICM7556ISD+T is supplied in Tape & Reel format. Both parts are suitable for applications requiring lower power consumption and extended temperature operation. Selection between these variants depends on packaging and handling requirements for production processes.

All three substitute parts maintain ROHS3 compliance and MSL Level 1 rating, ensuring regulatory conformance and manufacturing compatibility with the original TLC552CD.

Frequently Asked Questions (FAQ)

Q: Can the TLC556CDR be used as a direct replacement for the TLC552CD?

A: The TLC556CDR is functionally compatible with the TLC552CD in applications where the supply voltage operates within the 2V ~ 15V range. Both parts share identical 14-SOIC packaging, surface mount mounting type, and operating temperature range (0°C ~ 70°C). The primary difference is the maximum supply voltage: the TLC552CD supports 1V ~ 18V, while the TLC556CDR supports 2V ~ 15V. If your application requires operation below 2V or above 15V, the TLC556CDR is not suitable.

Q: What is the difference between ICM7556ISD+ and ICM7556ISD+T?

A: Both parts are electrically and functionally identical. The difference is packaging format: ICM7556ISD+ is supplied in Tube packaging, while ICM7556ISD+T is supplied in Tape & Reel format. Selection depends on your production process requirements and handling preferences. Tape & Reel format is typically preferred for automated assembly lines, while Tube packaging is suitable for manual assembly or lower-volume applications.

Q: Why do the substitute parts have different frequency ratings?

A: The frequency rating of a 555-type timer IC is determined by external timing components (resistors and capacitors) in the application circuit. The IC's maximum operating frequency specification indicates the highest frequency at which the IC can reliably operate. The TLC552CD operates at 2.8MHz maximum, the TLC556CDR at 2.1MHz maximum, and the ICM7556 variants at 500kHz maximum. If your application requires operation at frequencies below these maximums, all parts are suitable. If your application requires operation above 500kHz, the ICM7556 variants are not suitable.

Q: Are all substitute parts RoHS compliant?

A: Yes. The TLC552CD and all three substitute parts (TLC556CDR, ICM7556ISD+, and ICM7556ISD+T) are ROHS3 compliant and carry MSL Level 1 (Unlimited) moisture sensitivity rating. All parts meet current regulatory requirements for hazardous substance restrictions.

Q: Which substitute part offers the lowest power consumption?

A: The ICM7556ISD+ and ICM7556ISD+T both offer the lowest supply current at 60 µA, compared to 1.6 mA for the TLC552CD and 720 µA for the TLC556CDR. If power consumption is a critical design parameter, the Analog Devices Inc./Maxim Integrated variants are the preferred choice.

Q: Can I use the ICM7556 variants in applications requiring operation below 2V?

A: No. The ICM7556ISD+ and ICM7556ISD+T have a minimum supply voltage of 2V. If your application requires operation at 1V, only the TLC552CD supports this voltage level. The TLC556CDR also has a minimum supply voltage of 2V and is not suitable for 1V operation.