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NXP Semiconductors BY329-1200,127
- Part No.:
- BY329-1200,127
- Manufacturer:
- NXP Semiconductors
- Category:
- Single Diodes
- Package:
- TO-220-2
- Datasheet:
-
BY329-1200,127.pdf
- Description:
- DIODE GEN PURP 1.2KV 8A TO220AC
- Quantity:
- Payment:
- Shipping:
Inventory:5,982
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Product details
Overview
BY329-1200,127 from NXP Semiconductors (formerly Philips) is a fast, soft-recovery glass-passivated rectifier diode in TO220AC (SOD59) package, rated for 1200 V peak repetitive reverse voltage (VRRM), 8 A average forward current (IF(AV)), and 135 ns maximum reverse recovery time (trr). It serves as a primary output rectifier in switched-mode power supplies for TVs and monitors.
For engineers reviewing the BY329-1200,127 datasheet, BY329-1200,127 pinout, BY329-1200,127 application, or BY329-1200,127 equivalent, key selection criteria include soft-recovery behavior for EMI reduction, low thermal resistance (Rth j-mb = 2.0 K/W), and high surge capability (IFSM = 75 A at 10 ms) in high-reliability consumer power systems.
Technical Context
The BY329-1200,127 employs double-diffused silicon construction with glass passivation to achieve fast switching (trr ≤ 135 ns) and soft reverse recovery-minimizing voltage overshoot and ringing during turn-off. Its soft recovery characteristic reduces electromagnetic interference in high-frequency SMPS topologies.
Designed for mounting on heatsinks via its isolated tab (pin 1 = cathode, pin 2 = anode, tab = cathode), it delivers stable operation up to 150 °C junction temperature with low forward voltage (VF = 1.85 V max at IF = 20 A) and low reverse leakage (IR ≤ 1.0 mA at VRWM and Tj = 125 °C).
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VRRM | 1200 V - Maximum repetitive reverse blocking voltage; defines safe operating range in high-voltage DC bus applications. |
| IF(AV) | 8 A - Average forward current at Tmb ≤ 122 °C; determines continuous power handling in rectifier stage of 100–200 W SMPS. |
| trr | ≤135 ns - Reverse recovery time at IF = 1 A, -dIF/dt = 50 A/µs; enables operation up to ~100 kHz with low switching loss. |
| Rth j-mb | 2.0 K/W - Junction-to-mounting-base thermal resistance; supports efficient heatsink coupling for sustained 8 A conduction. |
| VF | 1.85 V max at IF = 20 A - Forward voltage drop; directly impacts conduction loss and thermal design margin in high-current paths. |
| IFSM | 75 A at t = 10 ms - Non-repetitive surge current rating; ensures robustness against line transients and startup inrush. |
Pinout & Package
Package: SOD59 (TO220AC), epoxy-encapsulated, 2-pin leaded device with isolated metal tab (cathode-connected). Mounting base electrically connected to cathode (pin 1); anode is pin 2. Net mass: 2 g. UL94 V0 compliant.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Pin 1 | Cathode | Main cathode terminal; electrically tied to mounting tab-requires insulated mounting hardware when tab is heatsinked. |
| Pin 2 | Anode | Input terminal for AC or switched input; carries full load current during forward conduction. |
| Tab | Cathode | Thermally conductive mounting surface; must be electrically isolated unless system ground reference permits direct cathode connection. |
Key Features
| Feature | Design Value |
|---|---|
| Soft recovery characteristic | Reduces voltage overshoot and EMI generation during diode turn-off, easing filter design in compact TV/monitor SMPS. |
| Glass passivation | Ensures long-term reliability and moisture resistance in consumer-grade environments without hermetic sealing. |
| Low Rth j-mb (2.0 K/W) | Enables effective thermal management using standard TO220 heatsinks, supporting 8 A continuous operation without forced air. |
| High IFSM (75 A) | Withstands repeated cold-start surges and transient overloads common in CRT and LCD display power supplies. |
Applications
| TV Power Supply Rectification | Monitor SMPS Output Stage |
|---|---|
Use Scenario: Primary high-voltage rectification in flyback or forward converter outputs delivering 100–200 W to CRT/LCD backlight and logic rails. IC Role / Device Role / Timing Role: High-voltage, medium-current output rectifier replacing slower diodes to reduce switching losses and improve efficiency. Use Value: Soft recovery minimizes snubber losses and EMI filter size; 1200 V rating accommodates 400 V DC bus with safety margin. | Use Scenario: Secondary-side rectification in multi-output SMPS for LCD monitor main +5 V, +12 V, and standby rails. IC Role / Device Role / Timing Role: Fast-recovery freewheeling diode in synchronous or quasi-resonant converters operating at 50–100 kHz. Use Value: 135 ns trr enables clean commutation with minimal tail current, reducing heat rise in confined chassis layouts. |
| Industrial AC-DC Adapter | LED Driver Input Bridge |
Use Scenario: Input rectification in universal-input (85–265 VAC), 150 W industrial AC-DC adapters requiring high reliability and thermal cycling endurance. IC Role / Device Role / Timing Role: Single-phase bridge leg diode with high thermal cycling performance and low Rth j-mb for extended service life. Use Value: 150 °C max junction temperature and 2.0 K/W thermal resistance support unattended operation in sealed enclosures. | Use Scenario: Input-stage rectifier in constant-current LED drivers for commercial signage, where EMI compliance is critical. IC Role / Device Role / Timing Role: Fast, soft-recovery diode in bridge configuration to minimize conducted emissions during zero-crossing transitions. Use Value: Low dIR/dt (50–60 A/µs) and controlled Qs (0.7 µC max) suppress high-frequency noise coupled into LED string control circuitry. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar fast rectifier applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| STTH8R06D | 600 V VRRM, 8 A IF(AV), trr = 65 ns, TO220AC package, higher speed but lower voltage rating. | Suitable only for ≤600 V DC bus designs; not interchangeable in 1200 V systems without redesign. | Select when higher switching frequency (>200 kHz) and lower trr are prioritized over voltage margin. |
| VS-8EWH06FN-M3 | 600 V VRRM, 8 A IF(AV), soft recovery, VF ≈ 1.75 V, TO220AC, Vishay Gen 3 Hyperfast diode. | Lacks 1200 V rating; optimized for ultra-low Qs in PFC stages-not recommended for primary HV rectification. | Prefer for PFC boost diodes or secondary-side rectifiers where 600 V suffices and EMI is critical. |
Compared with STTH8R06D and VS-8EWH06FN-M3, the BY329-1200,127 uniquely balances 1200 V blocking, soft recovery, and proven thermal robustness for legacy TV/monitor SMPS-making it irreplaceable in existing 1200 V designs without layout or safety requalification.
Availability
BY329-1200,127 is available at Aetrix Electronics and suitable for TV power supply rectification, monitor SMPS output stages, and industrial AC-DC adapters requiring stable component supply and long-lifecycle support.
Supply support for BY329-1200,127 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
NXP Semiconductors is a global semiconductor leader specializing in secure connectivity solutions, automotive ICs, and analog/power discrete devices, with roots in Philips' semiconductor division.
The BY329 series was developed by Philips specifically for high-reliability, cost-sensitive consumer power applications-including CRT and flat-panel display power supplies-emphasizing thermal resilience, soft switching, and long-term stability under thermal cycling.
FAQ
What is the maximum junction temperature rating for the BY329-1200,127?
The BY329-1200,127 has a maximum operating junction temperature (Tj) of 150 °C, as specified in the Absolute Maximum Ratings table. This rating allows reliable operation in enclosed, convection-cooled environments typical of TV and monitor power supplies. Derating curves in the datasheet define allowable IF(AV) versus mounting base temperature to ensure Tj remains within limit.
Is the BY329-1200,127 pin-compatible with other TO220AC rectifiers like the BY229 series?
Yes-the BY329-1200,127 uses the standard SOD59 (TO220AC) footprint with pin 1 = cathode and pin 2 = anode, matching mechanical and electrical pinout of BY229-1200 and similar TO220AC rectifiers. However, differences in trr, VF, and soft recovery behavior mean functional substitution requires validation in the target circuit's switching waveform and thermal profile.
Does the BY329-1200,127 have a built-in thermal protection feature?
No-the BY329-1200,127 is a passive rectifier diode with no integrated thermal shutdown or sensing. Protection relies entirely on external thermal design: proper heatsinking, ambient temperature control, and current derating per the datasheet's IF(AV) vs. Tmb curves. Its 2.0 K/W Rth j-mb enables predictable thermal modeling without active intervention.
What is the reverse recovery charge (Qs) specification for the BY329-1200,127?
The BY329-1200,127 has a maximum reverse recovery charge (Qs) of 0.7 µC, measured at IF = 2 A, VR > 30 V, and -dIF/dt = 20 A/µs. This low Qs value-combined with soft recovery-reduces switching loss and EMI in high-frequency SMPS, especially when paired with MOSFETs in quasi-resonant topologies.
Can the BY329-1200,127 be used in a bridge rectifier configuration?
Yes-the BY329-1200,127 is a single-diode device rated for 1200 V reverse blocking and can be used in discrete full-wave bridge configurations (e.g., four units per bridge). Its soft recovery and low trr make it suitable for high-efficiency bridges in offline SMPS, though discrete bridges require careful layout to balance thermal and parasitic inductance across all four legs.
BY329-1200,127 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- NXP Semiconductors
- Series:
- -
- Package/Case:
- TO-220-2
- Packaging:
- Tube
- Product Status:
- Obsolete
- Technology:
- Standard
- Voltage - DC Reverse (Vr) (Max):
- 1200 V
- Current - Average Rectified (Io):
- 8A
- Voltage - Forward (Vf) (Max) @ If:
- 1.85 V @ 20 A
- Speed:
- Fast Recovery =< 500ns, > 200mA (Io)
- Reverse Recovery Time (trr):
- 135 ns
- Current - Reverse Leakage @ Vr:
- 1 mA @ 1000 V
- Capacitance @ Vr, F:
- -
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- TO-220AC
- Operating Temperature - Junction:
- 150°C (Max)
BY329-1200,127 FAQ
1.How can I place an order for BY329-1200,127 through Aetrix?
Please submit a Request for Quotation (RFQ) for BY329-1200,127 on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for BY329-1200,127 reliable?
The price and inventory of BY329-1200,127 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BY329-1200,127 is usually 5 days.
3.What payment methods are accepted for BY329-1200,127?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BY329-1200,127 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BY329-1200,127?
BY329-1200,127 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BY329-1200,127 order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for BY329-1200,127?
For technical support, including BY329-1200,127 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BY329-1200,127 requirements.
6.How does Aetrix verify that BY329-1200,127 is sourced from the original manufacturer or authorized distributors?
All BY329-1200,127 products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that BY329-1200,127 meets industry standards.
7.What is the process for return or replacement of BY329-1200,127?
All BY329-1200,127 units undergo pre-shipment inspection (PSI). If there is an issue with BY329-1200,127, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The BY329-1200,127 part is unused and in its original packaging.
Return procedure for BY329-1200,127:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BY329-1200,127 Tags
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