Current Sources and Voltage References

438

Applying the bandgap shunt reference

The operating temperature is a major factor, because all references are affected by

temperature, thereby having a tempco and a thermal hysteresis. The operating temper-

ature range will govern your choice of reference, because some otherwise acceptable

devices may not be suitable for that particular range (usually at under –40°C and over

+85°C extremes). In many cases the device is used to provide a reference scale to an

A/D or D/A converter, and the temperature span will directly reflect on the reference’s

drift. All converters have a bit-resolution and a scale factor tempco (i.e., gain error),

which will directly ...