NXP Semiconductors BY359-1500,127

Overview

BY359-1500,127 from NXP Semiconductors (formerly Philips) is a fast-recovery, high-voltage damper diode in SOD113 package, rated for 1500 V peak repetitive reverse voltage (VRRM), 15.7 A RMS forward current (IF(RMS)), and ≤600 ns reverse recovery time (trr). It features soft recovery, isolated mounting tab, and low forward voltage drop (VF ≤ 1.8 V at 20 A, 25 °C), designed specifically for horizontal deflection circuits in CRT TV receivers.

For engineers reviewing the BY359-1500,127 datasheet, BY359-1500,127 pinout, BY359-1500,127 application, or BY359-1500,127 equivalent, key selection criteria include VRRM compliance for flyback energy handling, trr and Qs values for EMI control in high-frequency sweep stages, thermal resistance to heatsink (Rth j-hs ≤ 4.8 K/W with compound), isolation voltage rating (Visol = 2500 V RMS), and cathode/anode terminal configuration for PCB layout and heatsink grounding.

Technical Context

This damper diode operates in high-dV/dt, high-di/dt horizontal deflection switch-mode environments where rapid turn-off and controlled reverse recovery are critical to suppress voltage overshoot and reduce snubber losses. Its soft recovery characteristic minimizes ringing and EMI generation during commutation of flyback transformers.

The device integrates an electrically isolated metal tab enabling direct mechanical mounting to a heatsink without additional insulation, while maintaining 2500 V RMS isolation between terminals and heatsink - essential for safety-critical CRT power supply and deflection stage designs operating at elevated ground-referenced potentials.

Key Specifications

Pinout & Package

Package: SOD113 - axial-leaded, glass-passivated, plastic-encapsulated diode with electrically isolated metal mounting tab. Dimensions: 15.8 mm length × 4.6 mm diameter; net mass 2 g; UL94 V0 compliant epoxy.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar damper diode applications.

Compared with STTH1602CG and BY359-1500,118, the BY359-1500,127 uniquely balances 1500 V ruggedness, soft recovery for CRT EMI control, and isolated-tab thermal design - making it irreplaceable in legacy TV/monitor horizontal deflection without redesigning heatsink isolation or snubber networks.

Availability

BY359-1500,127 is available at Aetrix Electronics and suitable for CRT television repair, monitor refurbishment, and industrial display maintenance requiring stable component supply and long-lifecycle support.

Supply support for BY359-1500,127 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 delivering high-performance analog, logic, and discrete solutions for automotive, industrial, and consumer electronics.

The BY359 series belongs to NXP's legacy high-voltage rectifier portfolio, engineered specifically for reliability-critical horizontal deflection and flyback damping in CRT-based video systems.

FAQ

What is the maximum junction temperature rating for BY359-1500,127?

The BY359-1500,127 has a maximum operating junction temperature (Tj) of 150 °C, validated under continuous RMS forward current and surge conditions. This rating enables reliable operation in thermally constrained CRT deflection circuits when mounted with thermal compound to a heatsink - Rth j-hs is specified at ≤4.8 K/W under those conditions. Derating is required above 100 °C ambient per the transient thermal impedance curve in the datasheet.

Does BY359-1500,127 have an electrically isolated mounting tab?

Yes, the BY359-1500,127 features an electrically isolated metal tab conforming to IEC 60134 isolation requirements. It provides 2500 V RMS isolation between both terminals and the external heatsink at 50–60 Hz, enabling direct mounting without insulating washers. This isolation is confirmed in the "Isolation Limiting Value & Characteristic" section of the Philips specification document.

What is the reverse recovery time (trr) specification for BY359-1500,127?

The BY359-1500,127 has a maximum reverse recovery time (trr) of 600 ns under test conditions of IF = 2 A, VR ≥ 30 V, and -dIF/dt = 20 A/µs at Tj = 25 °C. Its soft recovery profile also limits peak reverse recovery current (Irrm) and charge (Qs ≤ 2.0 µC), reducing EMI generation in horizontal deflection switching applications.

Can BY359-1500,127 be used as a direct replacement for BY359X-1500?

Yes, BY359-1500,127 is the commercial designation for the BY359X-1500 variant - the "X" suffix denotes the family, and "127" indicates the specific packaging format (ammo pack). All electrical, thermal, and mechanical specifications including VRRM = 1500 V, IF(RMS) = 15.7 A, and SOD113 package are identical between BY359-1500,127 and BY359X-1500 as documented in the Philips product specification Rev 1.300.

What is the forward voltage drop of BY359-1500,127 at 10 A and 150 °C?

The BY359-1500,127 exhibits a maximum forward voltage drop (VF) of 1.5 V at 10 A and junction temperature of 150 °C, per the Static Characteristics table in the Philips datasheet. At room temperature (25 °C), VF is ≤1.8 V at 20 A - confirming low conduction loss across its full operating temperature range.