TL594CNG4 Equivalent & Substitute Parts

Part Overview

The TL594CNG4 is a PWM controller IC manufactured by Texas Instruments, designed for multiple DC-DC converter topologies including buck, boost, flyback, forward converter, full-bridge, half-bridge, and push-pull configurations. This component provides transistor driver outputs with integrated dead time control and frequency control features, supporting supply voltages from 7V to 40V and switching frequencies up to 300kHz.

The TL594CNG4 is discontinued at DiGi Electronics, necessitating identification of functionally equivalent alternatives for ongoing design support and component procurement. Substitute parts must maintain compatibility across topology support, output configuration, control features, and physical packaging to ensure direct replacement capability.

Substiute Parts

TL594CNG4

Texas InstrumentsIn Stock: 1185TL594CNG4 Datasheet

Current PartRFQ

TL594CN

onsemiIn Stock: 9496TL594CN Datasheet

MFR RecommendedRFQ

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 TL594CNG4 are evaluated based on the following critical parameters that determine functional equivalence:

Primary Substitution Criteria:

• Package / Case: 16-DIP (0.300", 7.62mm) form factor
• Output Type: Transistor Driver configuration
• Output Configuration: Positive output
• Voltage - Supply (Vcc/Vdd): 7V ~ 40V range
• Control Features: Dead Time Control and Frequency Control
• Number of Outputs: 2 outputs
• Mounting Type: Through Hole

Topology Compatibility: Substitute parts must support at minimum the buck and push-pull topologies, with preference for parts supporting the full topology range of the original component.

Compliance Considerations: RoHS3 compliance and REACH unaffected status are maintained across all substitute options.

Three substitute parts meet these criteria with varying levels of functional overlap and product status.

Parameter Comparison

Engineering Selection Recommendations

Primary Recommendation: TL594IN

The TL594IN from Texas Instruments is the optimal substitute for the TL594CNG4. This part maintains identical topology support across all seven converter types (buck, boost, flyback, forward converter, full-bridge, half-bridge, push-pull), matching the original component's functional range. The TL594IN preserves the same switching frequency capability (1kHz ~ 300kHz), maximum duty cycle (97%), and control feature set. Both parts are ROHS3 compliant and REACH unaffected. The TL594IN carries active product status, ensuring long-term availability and supply chain stability. Operating temperature range extends to -40°C ~ 85°C, providing broader environmental coverage than the original 0°C ~ 70°C specification.

Secondary Recommendation: TL594CN

The TL594CN from onsemi provides functional substitution with reduced topology support, covering buck and push-pull configurations. This part maintains the 7V ~ 40V supply voltage range, 16-DIP package format, and integrated dead time and frequency control features. The TL594CN operates at a fixed 300kHz switching frequency with 96% maximum duty cycle. However, this part is RoHS non-compliant and carries obsolete product status, limiting its suitability for new designs requiring regulatory compliance.

Limited Compatibility: AZ494AP-E1

The AZ494AP-E1 from Diodes Incorporated is a fixed-output buck regulator with significantly reduced functionality compared to the TL594CNG4. This part supports only step-down topology with a fixed 4.95V output and 200mA current rating, making it unsuitable for applications requiring programmable output voltage or multi-topology support. The AZ494AP-E1 is obsolete and should be considered only for legacy system maintenance where the specific fixed output voltage and current rating match application requirements.

Frequently Asked Questions (FAQ)

Q: Can the TL594IN directly replace the TL594CNG4 in existing designs?

A: Yes. The TL594IN maintains identical topology support, control features, and electrical specifications. Both parts use the 16-DIP package and support the same 7V ~ 40V supply voltage range with switching frequencies from 1kHz to 300kHz. The TL594IN's extended operating temperature range (-40°C ~ 85°C versus 0°C ~ 70°C) provides additional environmental margin. Pin-for-pin compatibility and functional equivalence are confirmed across all specified parameters.

Q: What are the key differences between TL594CN and TL594IN?

A: The primary difference is topology support. The TL594IN supports seven topologies (buck, boost, flyback, forward converter, full-bridge, half-bridge, push-pull), while the TL594CN supports only two (buck, push-pull). The TL594CN operates at a fixed 300kHz switching frequency, whereas the TL594IN provides programmable frequency from 1kHz to 300kHz. The TL594CN includes synchronous rectifier capability; the TL594IN does not. The TL594IN is ROHS3 compliant and active; the TL594CN is RoHS non-compliant and obsolete.

Q: Is the AZ494AP-E1 suitable as a substitute?

A: The AZ494AP-E1 is not a functional substitute for the TL594CNG4. The AZ494AP-E1 is a fixed-output buck regulator with 4.95V output and 200mA current rating, designed for specific low-power applications. The TL594CNG4 is a programmable PWM controller supporting multiple topologies and output configurations. These parts serve fundamentally different application categories and are not interchangeable.

Q: Does package compatibility guarantee electrical compatibility?

A: No. While all substitute parts use the 16-DIP package, electrical compatibility depends on matching topology support, control features, output configuration, and voltage specifications. The AZ494AP-E1, despite sharing the 16-DIP package, is not electrically compatible due to its fixed-output architecture and limited topology support. Always verify topology requirements, frequency range, and control feature compatibility before substitution.

Q: What compliance considerations apply to substitute selection?

A: The TL594CNG4 is ROHS3 compliant and REACH unaffected. The TL594IN maintains both certifications, making it suitable for applications with regulatory compliance requirements. The TL594CN is RoHS non-compliant, restricting its use in regulated markets. The AZ494AP-E1 is ROHS3 compliant but obsolete. For new designs, select parts with active product status and current compliance certifications.

Q: How does switching frequency capability affect substitution?

A: The TL594CNG4 supports programmable switching frequencies from 1kHz to 300kHz, enabling optimization for specific converter designs. The TL594IN maintains this range. The TL594CN operates at fixed 300kHz, limiting frequency optimization. The AZ494AP-E1 operates at fixed 40kHz. Applications requiring frequencies below 300kHz or specific frequency tuning require the TL594IN or TL594CNG4; the TL594CN and AZ494AP-E1 are unsuitable for such designs.