Magnetic head circuit having a write current changeover circuit with a clamp voltage depending on write current for high-speed data transfer
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United States of America Patent
Stats
-
Feb 21, 1995
Grant Date -
N/A
app pub date -
Jan 28, 1993
filing date -
Jan 30, 1992
priority date (Note) -
In Force
status (Latency Note)
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Abstract
A magnetic head circuit for a plurality of magnetic heads includes two emitter follower transistors for receiving magnetic head writing data, two differential transistors connected to the two emitter follower transistors for performing differential operation control thereover, and two resistors connected to collectors of the two differential transistors for supplying a base current to the two emitter follower transistors, and wherein the emitter follower transistors are connected in series with each other to perform differential switch operations over a magnetic head writing current. A magnetic head fly-back voltage has a clamp voltage which varies according to a writing current flowing through a pair of signal terminals. A pair of differential transistors, whose bases are connected to the pair of signal terminals and whose emitters are connected directly to each other, are operated according to a voltage appearing between the pair of signal terminals. Connected to the collectors of the pair of differential transistors are amplification transistors respectively. Connected to outputs of the amplification transistors are post-amplifiers. Such a connection configuration provides a small mirror capacitance as viewed from the bases of the amplification transistors. A high writing and reading accessing speed to the magnetic heads can be realized.

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- 15 United States
- 10 France
- 8 Japan
- 7 China
- 5 Korea
- 2 Other
Patent Owner(s)
Patent Owner | Address | |
---|---|---|
RENESAS ELECTRONICS CORPORATION | TOKYO |
International Classification(s)
Inventor(s)
Inventor Name | Address | # of filed Patents | Total Citations |
---|---|---|---|
Hatanaka, Noriaki | Chigasaki, JP | 16 | 149 |
Hirai, Tomoaki | Odawara, JP | 40 | 300 |
Hirose, Tsuyoshi | Ome, JP | 44 | 295 |
Kaji, Tadao | Tokyo, JP | 5 | 147 |
Nagaya, Yuji | Ome, JP | 13 | 164 |
Yoshinaga, Masaki | Tachikawa, JP | 23 | 149 |
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Fee | Large entity fee | small entity fee | micro entity fee | due date |
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Fee | Large entity fee | small entity fee | micro entity fee |
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Surcharge after expiration - Late payment is unavoidable | $700.00 | $350.00 | $175.00 |
Surcharge after expiration - Late payment is unintentional | $1,640.00 | $820.00 | $410.00 |
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