Differential amplifier with gain compensation
First Claim
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1. A gaincompensated differential amplifier circuit comprising:
 (a) a transistor differential amplifier, with reasonably matched current gains, operating at a tail current I_{tail} ;
(b) a transistor current source responsive to a control voltage for generating said tail current as a function of the control voltage;
(c) control voltage generating means for generating, as the control voltage, a voltage which varies proportionately to absolute temperature; and
(d) the control voltage generating means including means for functionally relating the control voltage to the intrinsic emitter resistance of the current source.
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Abstract
A differential amplifier including circuit means for generating a tail current which is not only porportional to absolute temperature, but also is adjusted to compensate for the nonideal transistor geometries and properties, including finite beta and nonzero, temperaturedependent intrinsic resistances, so as to result in an amplification ratio which is substantially independent of all component variations.
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1. A gaincompensated differential amplifier circuit comprising:

(a) a transistor differential amplifier, with reasonably matched current gains, operating at a tail current I_{tail} ; (b) a transistor current source responsive to a control voltage for generating said tail current as a function of the control voltage; (c) control voltage generating means for generating, as the control voltage, a voltage which varies proportionately to absolute temperature; and (d) the control voltage generating means including means for functionally relating the control voltage to the intrinsic emitter resistance of the current source.  View Dependent Claims (2, 3, 4, 5)


6. A gaincompensated differential amplifier circuit comprising:

(a) a transistor differential amplifier, with reasonably matched current gains, operating at a tail current I_{tail} ; (b) a current source responsive to a control voltage for generating said tail current as a function of the control voltage; (c) control voltage generating means for generating, as the control voltage, a voltage which varies proportionately to absolute temperature, and which is provided by a Δ
V_{BE} cell; and(d) the Δ
V_{BE} cell including means for functionally relating the control voltage to the intrinsic emitter resistance of the current source.  View Dependent Claims (7, 8, 9, 10)

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