Power Products in 3 Images or Less 

ISSUE: September 2009 

1-A,  200-V Ultrafast Rectifier Comes in MicroSMP

Vishay Intertechnology’s MUH1Px series of low-profile, surface-mount 1-A ultrafast rectifiers feature reverse-voltage ratings of 100 V, 150 V, or 200 V; and a reverse-recovery time of 25 ns for high-frequency applications. These devices include what’s described as the industry's first 1-A, 200-V ultrafast rectifier (the MUH1PD) in a super miniature package (Fig 1). The MicroSMP package occupies a footprint of just 2.5 mm by 1.3 mm and has a profile of 0.65 mm.

Prior to the introduction of the MUH1PD, the 1-A, 200-V rectifier required an SMP package, which occupies about twice the footprint of the MicroSMP. Similar ratings are also available in the common SMA package, which has a footprint four times that of the MicroSMP (Fig 2.) According to R. S. Chin, product marketing manager for rectifiers at Vishay, improvements in rectifier design together with the better thermal performance of the MicroSMP package, enable rectifiers in this smaller package to achieve the same power ratings as rectifiers in the much-larger SMA.

The MUH1Px rectifiers employ a planar structure that makes use of more die area than older, glass-passivated rectifiers based on a mesa structure. Meanwhile, both the SMP and MicroSMP packages improve thermal performance versus the SMA by increasing the cathode-side metallization (the die-attach pad on the SMP and MicroSMP). This increase in metallization reduces thermal resistance from the rectifier die to the pc board.

The MUH1Px rectifiers feature a high average forward current of 1 A, forward surge capability of 10 A, low forward-voltage drop, and a low leakage current of 1 μA. The rectifiers feature a maximum junction temperature of 175°C. Target applications include secondary rectifiers and freewheeling diodes in ac-dc power supplies, dc-to-dc converters, and battery chargers. Pricing in 10,000-piece quantities starts at $0.03 per piece.

Fig 1. 1-A ultrafast rectifiers offer ratings of 100 V, 150 V, or 200 V in the MicroSMP package.

Fig 2. The 1.3-mm x 2.5-mm MicroSMP has a footprint approximately half that of the
2.03-mm x 3.85-mm SMP, which in turn has half the footprint of the 2.665-mm x 5.105-mm SMA package.
The MUH1PD 1-A, 200-V ultrafast rectifier in the MicroSMP can replace existing rectifiers in the two larger packages.

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