摘要 |
A method for generating a programmable bandgap output reference voltage (VREF31) and a voltage reference circuit (31) have been provided. The voltage reference circuit (31) includes a pair of bipolar transistors (33, 34), a resistor (36), an operational amplifier (32) and a plurality of field effect transistors (38, 39, 41) configured to generate a current (I1') having a positive temperature coefficient. In addition, the voltage reference circuit (31) includes a resistor (46), an operational amplifier (44), another plurality of field effect transistors (47, 48) which, in conjunction with one (34) of the pair of bipolar transistors, generates a current (I2') having a negative temperature coefficient. The current (I1') having the positive temperature coefficient is summed with the current (I2') having the negative temperature coefficient to form a current having a zero temperature coefficient, which is used to develop a voltage having a zero temperature coefficient.
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