US 5,331,477 AGranted

Low voltage, constant current magnetic transducer drive system for digital recording

AssigneeTEAC Corporation

InventorSho Sugiyama

Life of this patent

Estimating the term…

Loading patent…

Abstract

A magnetic transducer has its opposite coil extremities connected to a direct current power supply via a pair of inductance elements, respectively. The transducer coil is excited not only from the power supply but from the inductance elements as a write control circuit applies a binary write control signal, representative of digital information to be recorded, to a pair of semiconductor switches thereby causing the same to be alternately turned on and off. Being typically in the form of metal oxide semiconductor field effect transistors, the semiconductor switches permit the flow therethrough of a current of varying magnitudes when open. A pair of reverse blocking diodes are therefore connected in series with the respective semiconductor switches in order to make constant the current flowing through the transducer.

Claims3

Dependent claims

A low voltage, constant current digital recording system comprising:

(a) a magnetic transducer having a coil;
(b) a direct current power supply;
(c) a pair of inductance elements connected respectively between a pair of opposite extremities of the transducer coil and a first terminal of the power supply;
(d) a pair of semiconductor switches connected respectively between the pair of opposite extremities of the transducer coil and a second terminal of the power supply;
(e) a write control circuit connected to the pair of semiconductor switches for applying thereto a binary write control signal representative of digital information to be recorded, in order to cause the semiconductor switches to be alternately turned on and off, with the consequent excitation of the transducer coil not only from the power supply but also from the inductance elements;
(f) a pair of reverse blocking diodes connected in series with the pair of semiconductor switches, respectively, in order to prevent current flow, during the excitation of the transducer coil with the closure of either of the semiconductor switches, through the other of the semiconductor switches;
and
(g) a pair of antiringing inductance elements connected in series with the pair of semiconductor switches, respectively;
(h) whereby the transducer coil can be excited with a more constant current, and with a lower supply voltage, than heretofore.

6 more elements

Dependencies are inferred from the claim text.

Facts

Application: 07/992,451Filed 17 Dec 1992
Priority: JP 3-112007[U]24 Dec 1991
Granted: 19 Jul 1994
Term ends: Not estimatedThe source records don’t support an estimate.

Classification5 codes

G11B 11/10508
Recording: by modulating only the magnetic field at the transducer
G11B 5/09
Recording, reproducing, or erasing methods; Read, write or erase circuits therefor: digital recording
H03K 17/6871
The devices being field-effect transistors: the output circuit comprising more than one controlled field-effect transistor
G11B
Information storage based on relative movement between record carrier and transducer

Family

No related US applications are recorded in the indexed filing history.

Timeline

Citations

Open elsewhere

Building an agent or pulling many patents? Use the API or MCP server instead of scraping pages. Get an API key