IDN-PID2145


Operating Characteristics

Temperature: -40 C to +85 C

Operating Voltage: +5V (4.80Vmin to 5.20Vmax)

Typical Supply Current: 50 mA

PID Controller Algorithm

When your application requires reaching a set point quickly with limited overshoot, PID control is an excellent solution. Ideanís PID algorithm incorporates proportional, integral (to eliminate steady-state errors) and derivative (to reduce overshoot and settling time) terms to rapidly reach the set point. Our algorithm responds to a set of previous inputs thus considering the trend of the feedback (input). This complete solution is embedded into a single controller and can be customized for your unique application.

Package Description

Package: DIP-28

 

Pin Description

PIN

NAME

DESCRIPTION

1

Set_Point

0 to +5V analog for defining the set point.

2

Sensor

0 to +5V analog input, provided by external sensor.

3

DAC

0 to +5V analog output, generated internally by the PID algorithm.

4

PWM

PWM digital output, generated internally by the PID algorithm.

5

DIR

Direction digital output, generated internally by the PID algorithm.

14

VSS

GND

24

EN

Digital input, which enables both the DAC and PWM outputs.

25

ID_Mode

Digital input, which sets pin ID to either Integral input (low) or Derivative input (high).

26

P

0 to +5V analog input, which is translated into the gain selected by the ID_Mode pin.

27

P

0 to +5V analog input, which is translated into Proportional gain.

28

VDD

+5 VDC

 

PID Coefficient Tuning

The Proportional Gain is used to reduce the rise time or the time needed to reach the target set point from the current pressure, but will not eliminate steady-state error. This gain also increases the tendency for the controller to overshoot the target as the controller becomes more aggressive.

The Integral Gain has the effect of eliminating the steady-state error.

The Derivative Gain has the effect of increasing the stability of the system, reducing the overshoot, and improving the transient response.

 

Tips

  1. Adjust the Proportional Gain to achieve the desired general response, while keeping the Integral and Derivative Gains set to 0.0000.
  2. Add the Derivative Gain to improve the overshoot.
  3. Add the Integral Gain to eliminate the steady-state error.
  4. Adjust the Proportional, Integral, and Derivative Gains as necessary to achieve the desired overall performance.