TL594ING4 Equivalent & Substitute Parts

Part Overview

The TL594ING4 is a multi-topology DC-DC controller IC manufactured by Texas Instruments, designed for buck, boost, flyback, forward converter, full-bridge, half-bridge, and push-pull regulator applications. It provides positive output step-up, step-down, and step-up/step-down conversion capabilities with integrated transistor driver output. The TL594ING4 is currently discontinued at DiGi Electronics, making equivalent substitute parts necessary for ongoing design support and production requirements.

Substiute Parts

TL594ING4

Texas InstrumentsIn Stock: 760TL594ING4 Datasheet

Current PartRFQ

TL594IN

Texas InstrumentsIn Stock: 7158TL594IN Datasheet

MFR RecommendedRFQ

AZ494AP-E1

Diodes IncorporatedIn Stock: 35472AZ494AP-E1 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the TL594ING4 are qualified based on the following criteria:

Primary Substitution Criteria:

• Identical or compatible package type (16-DIP, 0.300", 7.62mm)
• Through-hole mounting compatibility
• Supply voltage range overlap (7V ~ 40V minimum)
• Switching frequency range compatibility (1kHz ~ 300kHz minimum)
• Positive output configuration
• Transistor driver output type
• Multi-topology support or equivalent functional scope

Substitute Parts Identified:

1. TL594IN (Texas Instruments) — Direct manufacturer equivalent with identical electrical specifications, active product status, and tube packaging
2. AZ494AP-E1 (Diodes Incorporated) — Functional substitute with compatible package, supply voltage, and operating temperature range; limited to buck topology with fixed 4.95V output

Parameter Comparison

Engineering Selection Recommendations

TL594IN (Recommended Primary Substitute)

The TL594IN is the preferred substitute for the discontinued TL594ING4. Both parts share identical electrical specifications, including supply voltage range (7V ~ 40V), switching frequency capability (1kHz ~ 300kHz), duty cycle maximum (97%), and multi-topology support. The TL594IN maintains active product status with Texas Instruments, ensuring long-term availability and supply chain stability. Both parts are ROHS3 compliant and share identical package specifications (16-DIP, 0.300", 7.62mm). The primary difference is packaging format: TL594ING4 uses standard DIP packaging while TL594IN is supplied in tube packaging. Pin-for-pin compatibility and functional equivalence are confirmed.

AZ494AP-E1 (Limited Scope Substitute)

The AZ494AP-E1 from Diodes Incorporated is a functional substitute only for applications requiring buck topology with fixed 4.95V output. This part is not suitable for designs requiring boost, flyback, forward converter, full-bridge, half-bridge, or push-pull topologies. The AZ494AP-E1 has a fixed switching frequency of 40kHz and fixed output voltage, eliminating the frequency control and multi-topology flexibility of the TL594ING4. The product status is obsolete, presenting potential long-term supply concerns. Use this substitute only when application requirements are strictly limited to buck conversion at 4.95V output with 200mA current capability.

Frequently Asked Questions (FAQ)

Q: Can TL594IN be used as a direct replacement for TL594ING4?

A: Yes. The TL594IN is a direct pin-for-pin and functional equivalent. Both parts have identical electrical specifications, operating ranges, and control features. The primary difference is packaging format (tube vs. standard DIP). No circuit modifications are required.

Q: What are the key differences between TL594IN and AZ494AP-E1?

A: The TL594IN is a multi-topology controller supporting buck, boost, flyback, forward converter, full-bridge, half-bridge, and push-pull topologies with programmable frequency (1kHz ~ 300kHz) and output voltage. The AZ494AP-E1 is a fixed-output buck regulator with 4.95V output and 40kHz fixed switching frequency. The AZ494AP-E1 cannot replace the TL594ING4 in applications requiring topology flexibility or variable output voltage.

Q: Is the AZ494AP-E1 suitable for my application?

A: The AZ494AP-E1 is suitable only if your design requires: buck topology exclusively, fixed 4.95V output voltage, 200mA maximum output current, and 40kHz switching frequency. If your application requires any other topology, variable output voltage, or frequency control, use TL594IN instead.

Q: Are all substitute parts RoHS compliant?

A: Yes. Both TL594IN and AZ494AP-E1 are ROHS3 compliant, matching the compliance status of the original TL594ING4.

Q: What is the supply voltage compatibility range across all parts?

A: TL594ING4 and TL594IN both support 7V ~ 40V supply voltage. AZ494AP-E1 supports 7V ~ 36V. Designs operating above 36V require TL594IN.

Q: Is the 16-DIP package identical across all three parts?

A: Yes. All three parts use 16-DIP (0.300", 7.62mm) through-hole packages with identical pin configurations and mechanical dimensions.

Q: What is the product availability status for each substitute?

A: TL594ING4 is discontinued. TL594IN is active and recommended for new designs. AZ494AP-E1 is obsolete and should be avoided for new production due to supply uncertainty.