原始名称记载: Analog Devices, Inc.

Various techniques are described to accurately measure a ratio between the two currents supplied by a current source in a BJT temperature sensor. In an approach, a resistor is included between the current source and the emitter terminal of the BJT. An analog-to-digital converter (ADC) measures the voltage across the resistor R for each of the two currents. These voltages are used to determine current ratios, which are then used to determine a temperature of the BJT. The techniques are not limited to use with BJTs and are applicable to other semiconductor devices including diodes.

Various techniques to eliminate the error caused by variable β coupled with a series resistance in BJTs are described. Multiple known currents are applied to a terminal of the BJT and a corresponding Vis generated. A resistor R is coupled in series with a base or emitter of the BJT and an analog-to-digital converter (ADC) is used to measure the voltage across the resistor R for each of the known currents. These voltages are used to determine ratios of β change, which are then used to determine a temperature of the BJT.