AnalogRead produces unstable values

I'm using LattePanda with Visual Studio and the Firmata library to detect temperature using an LM35 sensor linked to Analog pin-1. However, even when the analog pin is connected to a steady +5V, the output swings by +/-5 counts. If I attach an external Arduino board to LattePanda and read the sensor value, the board works perfectly. How do I get a consistent analog reading from LattePanda? basketball stars
Please help me get out of this.