Push-Pull Transformer: VOOHU WHST06E14A1 vs. Würth Elektronik 750315371 Replacement Assessment

1. Competitor Product Overview (Würth Elektronik)

Würth Elektronik 750315371 belongs to the WE-PPTI push-pull transformer portfolio. It has centre-tapped primary and secondary windings with a 1:1.1 turns ratio. Its typical push-pull reference is 4.5-5.5 V input, 5 V / 1 A output and 400 kHz switching. In an alternative review, confirm the centre-tap terminals and polarity first, then magnetising inductance, volt-second capability and DCR; six leads and a similar turns ratio do not make an existing board interchangeable.

2. VOOHU Replacement Overview (Suzhou VOOHU Electronic Technology Co., Ltd.)

VOOHU WHST06E14A1 is a six-lead transformer for automotive applications, and VOOHU lists the WHST06E family among its push-pull transformer series. The part uses a 1CT:1.1CT winding, states 475 μH minimum OCL at 100 kHz, 0.1 V and 25°C, and gives a 3000 VAC, 1 mA, 2 s isolation condition. It is a valid comparison candidate for a centre-tapped push-pull transformer selection, but its magnetic values and footprint differ materially from 750315371. Treat an existing-board change as a redesign and validation exercise, not as a pin-to-pin substitution.

3. Key Parameter Comparison

Handle this pair in two passes: centre-tapped topology and turns ratio decide whether it belongs in the same selection round; inductance, DCR, volt-second capability, package and pads decide whether it can land on the same PCB. The table only brings together conditions stated for both parts. A close-looking number is not a direct replacement decision.

Notes:

1. Both parts use six leads with centre taps on the primary and secondary, and both state a total 1:1.1 ratio. Before connecting a controller, confirm the winding polarity, centre-tap function and real drive waveform across pins 1-2-3 and 6-5-4.
2. The 72 μH and 475 μH values are both stated at 100 kHz, but with 10 mVAC and 0.1 V excitation respectively, and VOOHU labels its value as OCL (TD & RD). They are not values that can be translated to the same operating point. Recalculate magnetising current and core flux with the actual frequency, duty cycle, dead time and volt-second product.
3. Würth lists 0.09 Ω maximum DCR separately for its two wound sides, while VOOHU labels 1000 mΩ maximum as TX & RX. Evaluate real current, allowed drop, PCB trace resistance and temperature rise together; do not decide from the two printed DCR values alone.
4. The Würth typical circuit is 4.5-5.5 V input, 5 V / 1 A output and 400 kHz. The VOOHU approval specification does not state a matching input range, output-current rating or volt-second limit, so those reference-circuit conditions cannot be carried across directly.
5. The two documents show different outlines and recommended pads. A 750315371 board changing to WHST06E14A1 needs package, land-pattern, pin-1, assembly-height and insulation-clearance CAD overlays, then start-up, full-load temperature, hi-pot and EMI validation on samples.
6. Würth explicitly states AEC-Q200 Grade 1; the VOOHU document states Meet AEC-Q200 Standard. For an automotive project that requires Grade 1, request the applicable grade and qualification evidence for WHST06E14A1 from the technical team.

4. Applications

1. New low-voltage isolated push-pull DC/DC designs with centre-tapped primary and secondary windings, where the controller frequency, volt-second product and target power establish the magnetic operating point.
2. Isolated auxiliary supplies for industrial RS485, CAN and isolated SPI interfaces, with common-mode interference, input surge and insulation boundaries checked on the PCB.
3. Automotive or industrial submodules with AEC-Q200 requirements, after the project reliability grade, operating-temperature range and insulation boundary are confirmed.
4. Existing Würth 750315371 board assessments or multi-source introduction for a new design: proceed with PCB redesign, samples and real-load validation, not as a drop-in package replacement.

5. FAQ

Can WHST06E14A1 directly replace Würth 750315371?

No. Both are six-lead centre-tapped structures with a total 1:1.1 turns ratio, but their inductance, DCR, typical operating point and package pads differ. Treat WHST06E14A1 as a comparison candidate that needs circuit recalculation and board validation, not as a pin-to-pin replacement.

Why does the same 1:1.1 turns ratio still require a circuit review?

Turns ratio only establishes the basic voltage relationship. The 750315371 typical application is 4.5-5.5 V to 5 V / 1 A at 400 kHz, while the WHST06E14A1 approval document does not state matching input, output or volt-second conditions. The 72 μH and 475 μH values also use different definitions and excitation levels, so magnetising current, duty margin, temperature rise and EMI must be checked again.

How should the DCR difference be evaluated?

Confirm the actual RMS and peak current for each winding, then calculate winding DCR with copper, via resistance, allowed voltage drop and temperature-rise limits. VOOHU's 1000 mΩ label is not split by side as the Würth values are, so confirm its definition with the technical team and measure samples when needed.

What should be tested on samples first?

Confirm terminal polarity and centre-tap wiring first. Then test start-up, output voltage, switching waveforms, core and winding temperature and efficiency at the real input voltage, frequency and load. Follow with hi-pot, EMI, pad assembly and system insulation-clearance checks.

Can an automotive project accept it as AEC-Q200 Grade 1 directly?

No. Würth explicitly lists Grade 1, while the VOOHU document only states Meet AEC-Q200 Standard. When Grade 1 is required, obtain the applicable grade, test report and customer-specification confirmation for WHST06E14A1 before release.

Why VOOHU?

One-stop sourcing: connectors + magnetics + interface chips, full support from selection to small-batch production.

Custom solutions: just share your application requirements and budget to get a tailored solution with professional technical support.

Fast development: direct from the manufacturer, rapid FAE response, efficient sampling, shorter time-to-market.

Core qualifications: ISO9001, ISO14001, RoHS, REACH; two in-house factories ensure delivery and quality.

For more information, visit VOOHU: China www.voohu.cn | Overseas www.voohuele.com | Technical support: song.lei@voohu.cn

Replacement Cross-Reference

Manufacturer: Würth Elektronik; Part No.: 750315371; key published parameters: six-lead centre-tapped windings, 1:1.1 ratio, 72 μH minimum at 100 kHz / 10 mVAC, 0.09 Ω maximum DCR per listed winding, 2500 V AC insulation test and -40 to +125°C operation. VOOHU WHST06E14A1 is a comparison candidate with 1CT:1.1CT ±5%, 475 μH minimum OCL at 100 kHz / 0.1 V and 3000 VAC at 1 mA for 2 s. It requires circuit and footprint redesign, not direct replacement. Contact VOOHU technical support for selection and validation guidance.