User manual

Toolbars and buttons116

7.2.1

PicoLog 1000 Series Digital Outputs control

Location:

Digital Outputs button on the Channels toolbar

Purpose:

controls the data logger's built-in signal generator

Digital Outputs dialog for the

PicoLog 1216

The range of controls available depends on which model of data logger you have.

PWM Output

PWM. The PWM output on some devices can be set to generate

a pulse-width modulated waveform. This is a logic signal that is

toggled with a specified period and duty cycle. The average

value of the signal is proportional to its duty cycle, so it can be

processed by an external low-pass filter to produce a signal that

is proportional to the duty cycle.

Off: Disable the PWM output.

PWM: Enable the PWM output with the specified

controllable Period and Duty Cycle.

Period. Select the duration of one cycle of the PWM output.

Duty Cycle. The percentage of the PWM signal period that the

signal spends at the logic high level. For example, if the period

is 1 ms and the duty cycle 25%, then the signal will spend 25%

of 1 ms = 250 s of each cycle at the logic high level, and the

remaining 750 s at the logic low level. The voltages of the logic

high and low levels are specified in the User's Guide for the data

logger, but are typically 0 volts (low) and 3.3 volts (high). Using

our example figures, the average value of the PWM output will

be 25% x 3.3 volts = 0.825 volts.

Digital Outputs

PicoLog PC Data Loggers have one or more digital outputs

capable of driving low-current loads.

Each output can be set to a high or low logic level by moving the

slider.