Powering AI processors – 48V vertical power delivery changes the game
AI models demand huge current, driving legacy multiphase designs past 50 phases—causing space, thermal, and control limits Vicor addresses
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Sine amplitude converters provide design flexibility
Vicor devices such as the VTM and BCM use the Sine Amplitude Converter Topology (SAC) to provide isolation and voltage transformation functions, allowing you to place these functions where they are required, separating them from regulation.
The SAC also allows a flexible approach to design: devices based upon this topology can be used on their own, or connected in series or parallel to provide higher output currents or voltages.
Figure 1 – Connecting VTMs in series and parallel
Figure 1 – Connecting VTMs in series and parallel
Example Application
Consider the following example: a regulated 200V rail is needed at the load from a 36V to 75V input voltage. To achieve this, four 50V output voltage SAC modules (VTMs) M1, M2, M3 and M4 of the same K factor of 1 are used. Input and output voltage is equal for a K factor of 1. Output current IOUT is common to all SAC modules. In this implementation, it is important to enable all SAC modules in a group to start all of them simultaneously for correct operation of resulting converter.
Total output voltage is the sum of output voltage given by all SACs connected in series output as given below for N number of SACs.
Where Total_VOUT = Total output voltage of series connect sine amplitude converters. N is the number of SAC modules. KN and VOUTN are the transformation factor and output voltage for each series connected SAC, VIN is the SAC input voltage which is equal to the output voltage of the regulator modules and VINS is the voltage of the unregulated input voltage source applied at the input terminals of the regulator.
The final system is shown below:
Figure 2: 50 V Input, 200 V Output Power Chain Using VTMs in Series
Figure 2: 50 V Input, 200 V Output Power Chain Using VTMs in Series
Related content
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Product overview: PRM and VTM
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Application note: PRM and VTM parallel array operation
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Application note: Creating higher voltage outputs using series connected sine amplitude converter
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