EP0400908A2
Expired / Lapsed
EP
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Line Driver
Assignee: ZF International UK Ltd
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Filing: 1990-05-25
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Granted: —
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Expires: 2010-05-25
Abstract
Abstract A line driver is provided for driving a twisted pair (LINE, LINE) with complementary data signals (DATA IN, DATA IN). The driver comprises NPN and PNP transistors (T1, T2) arranged as emitter followers with the emitters connected to the twisted pair (LINE, LINE) and to a biasing resistor network (R1, R2, R3). The line driver provides accurately symmetrical signals and its outputs can be used as "wired-or" outputs.
Inventors
- 👤 Mark Jonathan Basten
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 13:23
CPC Classifications
H; H04; H04L; H04L25/00; H04L25/02; H04L25/0264; H04L25/028; H03; H03K; H03K19/00; H03K19/0175; H03K19/018; H03K19/01825; H03K5/00; H03K5/15; H03K5/151; H04L25/0272
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
62 words
A line driver comprising first and second emitter followers having first and second inputs, respectively, for receiving complementary input signals and first and second outputs, respectively, for connection to first and second lines, respectively, and a biasing resistor network connected to the first and second outputs, characterised in that the second emitter follower (T2) is complementary to the first emitter follower (T1).
Claim 2
Dependent Claim
62 words
A line driver comprising first and second emitter followers having first and second inputs, respectively, for receiving complementary input signals and first and second outputs, respectively, for connection to first and second lines, respectively, and a biasing resistor network connected to the first and second outputs, characterised in that the second emitter follower (T2) is complementary to the first emitter follower (T1).
Claim 3
Dependent Claim
36 words
A line driver as claimed in Claim 1, characterised in that the first emitter follower (T1) comprises a bipolar transistor of NPN type and the second emitter follower (T2) comprises a bipolar transistor of PNP type.
Claim 4
Dependent Claim
61 words
A line driver as claimed in Claim 1 or 2, characterised in that the biasing resistor network (R1, R2, R3) comprises a first resistor (R2) connected between the first and second outputs, a second resistor (R3) connected between the first output and a first voltage source, and a third resistor (R1) connected between the second output and a second voltage source.
Claim 5
Dependent Claim
32 words
A line driver as claimed in Claim 3 when dependent on Claim 2, characterised in that the voltage of the first voltage source is less than that of the second voltage source.
Claim 6
Dependent Claim
26 words
A line driver as claimed in Claim 3 or 4, characterised in that the first and second voltage sources comprise first and second supply lines, respectively.
Claim 7
Dependent Claim
55 words
A line driver as claimed in Claim 5 when dependent on Claim 2, characterised in that the base of the NPN transistor (T1) is connected via a fourth resistor (R9) to the first supply line and the base of the PNP transistor (T2) is connected via a fifth resistor (R8) to the second supply line.
Claim 8
Dependent Claim
32 words
A line driver as claimed in Claim 6, characterised in that at least one of the fourth and fifth resistors (R9, R8) is connected in series with a normally forward-biased diode (D3).
References Cited (Backward Citations)
No citation records indexed.
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