AD584SH (nominal 4.5-30V input, nominal output current 10mA,operating −55°C to +125°C), as shown in the figure, 5V input, configured with 2.5V output.
The load impedance is around 350 ohms, 2.5V/350 Ω=7.14mA, AD584SH has an output capacity of 10mA, a temperature above 0 ℃, operates normally, and outputs 2.495V; At temperatures below -5 ℃, after power on, the output is 1.62V. After working for a period of time, the output is normal at 2.495V (presumably due to heating after working for a period of time causing the temperature to rise).
The hot air gun blowing will also restore normal 2.5V.
Replace the chip output with a resistance of 200 Ω to ground to eliminate the variation of load impedance with temperature. At low temperatures, output 1.25V, blow with a hot air gun, and restore to 2.5V.
Replace with a resistance of 2k Ω to ground and output 2.5V at low temperatures. It is speculated that the output capacity drops sharply at low temperatures.
Replace with AD584TH, which is identical to the above phenomenon. Speculatively ruling out device batch issues.
Change the input voltage from 5V to 12V, and output 2.5V normally at low temperatures.
May I ask what is the mechanism behind this phenomenon and if there are any issues with my schematic design?
