Programmable power supply

This page documents the config keys are various other info needed to write a libsigrok frontend for controlling programmable power supplies.

TODO

• Some way to specify fixed values for voltage and current, for devices that have one or more of these fixed in some channels. Two options:
  • A boolean key _FIXED, per channel
  • A _MIN corresponding to _MAX: When set to the same as _MAX, denotes a fixed setting for that channel. This would also allow negative values, for e.g. a range -5V - 5V
  • TODO: This is no longer a problem?
• Over temperature protection: need some examples of whether this is ever something that is gettable/settable, or is only ever a hardware feature.
  • Seems like the Rigol DP800 driver implemented this as a gettable/settable feature.

Notes

It's not unusual for different channels on a device to have different voltage or current limits. Therefore, channels will generally be in a probe group which allows setting these limits.

After setting SR_CONF_CHANNEL_CONFIG, the limits of these channels may change, and the limits should be queried again.

Config keys

A libsigrok driver for a programmable power supply implements all or some subset of the following config keys.

SR_CONF_POWER_SUPPLY

Denotes a device that provides power output via one or more output channels, typically with voltage and current set via the sigrok driver.

SR_CONF_VOLTAGE

• double, representing voltage.
• get: The current output voltage. This may not be the same as what was set -- the output may be disabled, or can change depending on the load.
• set: NA
• list: NA

SR_CONF_VOLTAGE_TARGET

• double, representing voltage.
• get: The previously set target output voltage, or device default.
• set: Set the target output voltage.
• list: Supported voltage range as (low, high, step).

SR_CONF_CURRENT

• double, representing current.
• get: The actual output current. This may not be the same as what was set -- the output may be disabled, or can change depending on the load.
• set: NA
• list: NA

SR_CONF_CURRENT_LIMIT

• double, representing current.
• get: The previously set output current limit, or device default.
• set: Set the output current limit.
• list: Supported current range as (low, high, step).

SR_CONF_OUTPUT_FREQUENCY

• double, representing frequency.
• get: The actual output frequency for AC power supplies. This may not be the same as what was set -- the output may be disabled, or can change depending on the load.
• set: NA
• list: NA

SR_CONF_OUTPUT_FREQUENCY_TARGET

• double, representing frequency.
• get: The previously set output frequency, or device default.
• set: Set the output frequency.
• list: Supported frequency range as (low, high, step).

SR_CONF_ENABLED

• boolean
• get: Actual state of output
• set: Turn output on or off
• list: NA

If a channel/probe group cannot be enabled or disabled separately from other channels, setting this key will return SR_ERR_NO. The set should then instead be tried with a NULL probe group, for devices that have only a global setting for this.

SR_CONF_CHANNEL_CONFIG

• string (e.g. "Independent", "Series", "Parallel", "Track1", "Track2")
• get: The channel output mode (e.g. independent, series or parallel)
• set: Set the channel output to independent (the default), series, or parallel.
• list: Supported channel modes.

SR_CONF_REGULATION

• string ("CV", "CC", "UR")
• get: The actual output regulation, e.g. constant current or constant voltage
• set: NA
• list: NA

SR_CONF_OVER_VOLTAGE_PROTECTION_ENABLED

• boolean
• get: TRUE, when the over voltage protection is enabled.
• set: Enable/disable over voltage protection.
• list: NA

SR_CONF_OVER_VOLTAGE_PROTECTION_ACTIVE

• boolean
• get: TRUE, when the over voltage protection threshold was reached.
• set: NA
• list: NA

SR_CONF_OVER_VOLTAGE_PROTECTION_THRESHOLD

• double, representing voltage.
• get: Actual over voltage protection threshold.
• set: Set over voltage protection threshold.
• list: Supported voltage threshold range as (low, high, step). (TODO: Implement!)

SR_CONF_OVER_CURRENT_PROTECTION_ENABLED

• boolean
• get: TRUE, when the over current protection is enabled.
• set: Enable/disable over current protection.
• list: NA

SR_CONF_OVER_CURRENT_PROTECTION_ACTIVE

• boolean
• get: TRUE, when the over current protection threshold was reached.
• set: NA
• list: NA

SR_CONF_OVER_CURRENT_PROTECTION_THRESHOLD

• double, representing current.
• get: Actual over current protection threshold.
• set: Set over current protection threshold.
• list: Supported current threshold range as (low, high, step). (TODO: Implement!)

SR_CONF_OVER_TEMPERATURE_PROTECTION

• boolean
• get: TRUE, when the over temperature protection is enabled.
• set: Enable/disable over temperature protection.
• list: NA