| 摘要 |
An amplifier circuit has an amplifier stage (10), comprising an amplifier transistor (104) with a gate coupled to an input (100) of the amplifier stag e (10), a source coupled to a reference connection (gnd) and a drain coupled t o a positive power supply connection (V+). A bias stage (12) is provided comprising a bias transistor (120), a drain resistance (124) and a source resistance (122), the bias transistor (120) having a gate coupled to a negative power supply connection (V-), a source coupled to the negative powe r supply connection (V-) via the source resistance (122) and a drain coupled t o the reference connection (gnd) via the drain resistance (124) and to the gat e of the amplifier transistor (104). The bias stage comprises a further resistance (20, 22), coupled from a node between the source of the bias transistor and the source resistance of the bias transistor (120) to a circu it node that carries a voltage higher than the voltage at the negative power supply connection.
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