Discrete-time PI controller that has been derived from the continuous-time PI controller
1 y = k * (1 + ---) * u T*s T*s + 1 = k * ------- * u T*s
by using the implicit Euler discretization formula. The block is parametrized with the gain k and the time constant T of the continuous PI block. As a result, the discrete-time form of the PI controller depends explicitly on the sample time of the controller and changing this sample time, will give still a similar performance.