Keithley 2220 transformer bipolar power supply series

Brief description of the series

Keithley 2220 is a series of maximum functional bipolar power supplies capable of supplying high-quality power to several independent electronic components. The series consists of 4 models, which differ from each other in the number of channels (2 or 3) and output power. Models 2220-30-1 and 2220G-30-1 contain two channels (30 V, 1.5 A, 45 W each). Models 2230-30-1 and 2230G-30-1 contain three channels (two of 30 V, 1.5 A, 45 W + third 6 V, 5 A, 30 W). Since the outputs of these transformer power supplies are galvanically isolated from each other, they can be connected in parallel (to increase current) and in series (to increase voltage or form a bipolar supply).

All models in this series come standard with a USB interface, which allows you to control their operation from a computer. In addition to the USB interface, models with the G index (2220G-30-1 and 2230G-30-1) contain an IEEE-488.2 (GPIB) interface. For detailed differences between the series models, see the interactive table. A full description of all the characteristics, as well as a driver for Labview and an IVI driver for MATLAB can be downloaded below on this page in the Documentation section.

All models of the series

The Keithley 2220 series consists of four models, which are presented in this interactive table. You can sort by any of the characteristics by simply clicking on its name in the table. To see all the characteristics of certain models, add them to the comparison.

Two and three channel models

Two of the four models in the Keithley 2220 series contain three fully independent channels with linear output voltage regulation. These are the Keithley 2230-30-1 and 2230G-30-1 models. Their appearance is shown in the photo below.

For simpler applications where two-channel power is sufficient, such as for bipolar audio circuits without a digital part, simplified models are available: Keithley 2220-30-1 and 2220G-30-1. These models are similar in all respects to three-channel ones, but are cheaper and contain only two galvanically isolated channels. Their appearance is shown in the photo below.

Bipolar power supply mode

When developing and repairing electronic equipment, it is often necessary to supply circuits with bipolar power. Because all Keithley 2220 series models are galvanically isolated from each other, they can be connected in series, making it easy to create a bipolar power supply. The figure below shows an example of such a combination of two channels. Please note that with this configuration, the positive and negative voltage adjustment is performed synchronously, which is very convenient.

Maximum functionality with three-channel models

Electronic devices often contain blocks that have "ground" pins that are not connected to each other. For example, in medical equipment, elements connected to a person must be isolated from the main circuit. Also, electrically isolated hardware modules are used in: data transmission systems over long distances, high-precision sensors, information collection systems in very noisy conditions, various systems with ADC and DAC, and many other cases.

The Keithley 2220 series has two models with three independent galvanically isolated channels. The figure below shows an example of using three isolated channels of the Keithley 2230G-30-1 to supply power to three separate pieces of medical equipment, which may be necessary when developing, setting up or repairing it.

Connecting power supplies to a computer

If it is necessary to connect Keithley 2220 series power supplies to a computer, this can be easily done using a standard USB interface, which is included in every instrument. And models with the G index, in addition to the USB interface, also contain a GPIB (IEEE-488.2) interface. Driver for Labview and IVI driver for MATLAB can be downloaded below on this page in the Documentation section.

This photo shows the rear panel of the 3-channel 2230G-30-1 model, showing the location of the USB and GPIB (IEEE-488.2) interface connectors. Also pay attention to the green group of contacts closed with plastic plugs – these contacts are used to compensate for voltage drops in the connection wires.

And this photo shows the rear panel of the two-channel model 2220-30-1, which has only a USB interface connector. The green group of contacts is used to compensate for voltage drops in the connection wires.