CXA1940N Datasheet, PDF (11/16 Pages) Sony Corporation – 4ch. Read/Write Amplifier for Thin Film Head of Hard Disk Drive

CXA1940N
Write unsafe detection circuit
Abnormal Write mode is detected.
In normal Write mode, WUS output turns to “Low” and in the following other conditions, WUS output turns to
“High”.
• Head input is open.
• Head input is shorted to GND.
• Write data frequency is abnormally low.
• No write current
• In read
• In power save
Power supply ON/OFF detection
VCC is monitored to avoid incorrecting Write.
Recording and Playback functions are inhibited as detected as abnormal when VCC decreases below the
power supply ON/OFF detector threshold voltage (VTH). When VCC is higher than VTH, the above inhibition is
released.
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