Two-coil fan driver - high voltage (alarm output)
US91A Melexis
24 V 2-coil fan driver with integrated alarm (rotation detection) output, available in 4-pin SIP (VA or VK), SOIC8 and SOT23 package options.
Top features
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Low cost
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High sensitivity Hall sensor
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Locked rotor protection and auto-restart
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Power-efficient CMOS and power MOSFETs
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Built-in output protection clamping diode
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Integrated alarm signal output
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SIP- package options: 4-pin VK or VA
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SMD package options: SOT23-5L straight leads and SOIC8 bent leads
- Drop-in replacement of US91
Product description
The US91A is a one-chip solution for driving two-coil brushless DC cooling fans.
Based on Melexis CMOS process, the integrated circuit contains a Hall-effect sensor, dynamic offset correction and low side output drivers.
The integrated alarm (RD) output is a safety signal which allow to detect if the fan rotates or not. Its open-drain output facilitates the connectivity with external interface for hardware monitoring. These features are combined with the Melexis patented no-VDD design to fit the IC in a small 4-pin VK or VA package. Also available in straight leads SOT23 and bent leads SOIC8 package.
Features and benefits
-
Low cost
-
High sensitivity Hall sensor
-
Locked rotor protection and auto-restart
-
Power-efficient CMOS and power MOSFETs
-
Built-in output protection clamping diode
-
Integrated alarm signal output
-
SIP- package options: 4-pin VK or VA
-
SMD package options: SOT23-5L straight leads and SOIC8 bent leads
- Drop-in replacement of US91
