SRS Model SR850 Lock-in Amplifier¶

Driver for SRS model SR850 lock-in amplifier.

Note that the sr850 will not usually work with list_instruments(), because it uses a non-standard termination character, and because one must first send the ‘OUTX’ command to specify which type of output to use.

class instrumental.drivers.lockins.sr850.AlarmMode(value)¶

An enumeration.

off = 0¶

on = 1¶

class instrumental.drivers.lockins.sr850.AuxInput(value)¶

An enumeration.

four = 4¶

one = 1¶

three = 3¶

two = 2¶

class instrumental.drivers.lockins.sr850.Ch1OutputSource(value)¶

An enumeration.

R = 1¶

X = 0¶

theta = 2¶

trace_1 = 3¶

trace_2 = 4¶

trace_3 = 5¶

trace_4 = 6¶

class instrumental.drivers.lockins.sr850.Ch2OutputSource(value)¶

An enumeration.

R = 1¶

Y = 0¶

theta = 2¶

trace_1 = 3¶

trace_2 = 4¶

trace_3 = 5¶

trace_4 = 6¶

class instrumental.drivers.lockins.sr850.CurrentGain(value)¶

An enumeration.

oneHundredMegaOhm = 1¶

oneMegaOhm = 0¶

class instrumental.drivers.lockins.sr850.Divide(value)¶

An enumeration.

AuxIn1 = 8¶

AuxIn1_2 = 20¶

AuxIn2 = 9¶

AuxIn2_2 = 21¶

AuxIn3 = 10¶

AuxIn3_2 = 22¶

AuxIn4 = 11¶

AuxIn4_2 = 23¶

F = 12¶

F_2 = 24¶

R = 3¶

R_2 = 15¶

R_n = 7¶

Rn_2 = 19¶

X = 1¶

X_2 = 13¶

X_n = 5¶

Xn_2 = 17¶

Y = 2¶

Y_2 = 14¶

Y_n = 6¶

Yn_2 = 18¶

theta = 4¶

theta_2 = 16¶

unity = 0¶

class instrumental.drivers.lockins.sr850.InputConfiguration(value)¶

An enumeration.

A = 0¶

A_B = 1¶

I = 2¶

class instrumental.drivers.lockins.sr850.InputCoupling(value)¶

An enumeration.

AC = 0¶

DC = 1¶

class instrumental.drivers.lockins.sr850.InputGround(value)¶

An enumeration.

floating = 0¶

ground = 1¶

class instrumental.drivers.lockins.sr850.LineFilter(value)¶

An enumeration.

both_filters = 3¶

line_2x_notch = 2¶

line_notch = 1¶

no_filters = 0¶

class instrumental.drivers.lockins.sr850.LowPassSlope(value)¶

An enumeration.

eighteen_dB_per_octave = 2¶

six_dB_per_octave = 0¶

twelve_dB_per_octave = 1¶

twentyfour_dB_per_octave = 3¶

class instrumental.drivers.lockins.sr850.Multiply(value)¶

An enumeration.

AuxIn1 = 8¶

AuxIn2 = 9¶

AuxIn3 = 10¶

AuxIn4 = 11¶

F = 12¶

R = 3¶

R_n = 7¶

X = 1¶

X_n = 5¶

Y = 2¶

Y_n = 6¶

theta = 4¶

unity = 0¶

class instrumental.drivers.lockins.sr850.OffsetSelector(value)¶

An enumeration.

R = 3¶

X = 1¶

Y = 2¶

class instrumental.drivers.lockins.sr850.OutputType(value)¶

An enumeration.

R = 3¶

X = 1¶

Y = 2¶

theta = 4¶

class instrumental.drivers.lockins.sr850.Parameter(value)¶

An enumeration.

units()¶

AuxIn_1 = 5¶

AuxIn_2 = 6¶

AuxIn_3 = 7¶

AuxIn_4 = 8¶

R = 3¶

X = 1¶

Y = 2¶

reference_frequency = 9¶

theta = 4¶

trace_1 = 10¶

trace_2 = 11¶

trace_3 = 12¶

trace_4 = 13¶

class instrumental.drivers.lockins.sr850.ReferenceSlope(value)¶

An enumeration.

sine_zero = 0¶

ttl_falling = 2¶

ttl_rising = 1¶

class instrumental.drivers.lockins.sr850.ReferenceSource(value)¶

An enumeration.

external = 2¶

internal = 0¶

internal_sweep = 1¶

class instrumental.drivers.lockins.sr850.ReserveMode(value)¶

An enumeration.

manual = 1¶

maximum = 0¶

minimum = 2¶

class instrumental.drivers.lockins.sr850.SR850¶

Interfaces with the SRS model SR850 Lock-in Amplifier

class AlarmMode(value)¶

An enumeration.

off = 0¶

on = 1¶

class AuxInput(value)¶

An enumeration.

four = 4¶

one = 1¶

three = 3¶

two = 2¶

class Ch1OutputSource(value)¶

An enumeration.

R = 1¶

X = 0¶

theta = 2¶

trace_1 = 3¶

trace_2 = 4¶

trace_3 = 5¶

trace_4 = 6¶

class Ch2OutputSource(value)¶

An enumeration.

R = 1¶

Y = 0¶

theta = 2¶

trace_1 = 3¶

trace_2 = 4¶

trace_3 = 5¶

trace_4 = 6¶

class CurrentGain(value)¶

An enumeration.

oneHundredMegaOhm = 1¶

oneMegaOhm = 0¶

class Divide(value)¶

An enumeration.

AuxIn1 = 8¶

AuxIn1_2 = 20¶

AuxIn2 = 9¶

AuxIn2_2 = 21¶

AuxIn3 = 10¶

AuxIn3_2 = 22¶

AuxIn4 = 11¶

AuxIn4_2 = 23¶

F = 12¶

F_2 = 24¶

R = 3¶

R_2 = 15¶

R_n = 7¶

Rn_2 = 19¶

X = 1¶

X_2 = 13¶

X_n = 5¶

Xn_2 = 17¶

Y = 2¶

Y_2 = 14¶

Y_n = 6¶

Yn_2 = 18¶

theta = 4¶

theta_2 = 16¶

unity = 0¶

class InputConfiguration(value)¶

An enumeration.

A = 0¶

A_B = 1¶

I = 2¶

class InputCoupling(value)¶

An enumeration.

AC = 0¶

DC = 1¶

class InputGround(value)¶

An enumeration.

floating = 0¶

ground = 1¶

class LineFilter(value)¶

An enumeration.

both_filters = 3¶

line_2x_notch = 2¶

line_notch = 1¶

no_filters = 0¶

class LowPassSlope(value)¶

An enumeration.

eighteen_dB_per_octave = 2¶

six_dB_per_octave = 0¶

twelve_dB_per_octave = 1¶

twentyfour_dB_per_octave = 3¶

class Multiply(value)¶

An enumeration.

AuxIn1 = 8¶

AuxIn2 = 9¶

AuxIn3 = 10¶

AuxIn4 = 11¶

F = 12¶

R = 3¶

R_n = 7¶

X = 1¶

X_n = 5¶

Y = 2¶

Y_n = 6¶

theta = 4¶

unity = 0¶

class OffsetSelector(value)¶

An enumeration.

R = 3¶

X = 1¶

Y = 2¶

class OutputType(value)¶

An enumeration.

R = 3¶

X = 1¶

Y = 2¶

theta = 4¶

class Parameter(value)¶

An enumeration.

units()¶

AuxIn_1 = 5¶

AuxIn_2 = 6¶

AuxIn_3 = 7¶

AuxIn_4 = 8¶

R = 3¶

X = 1¶

Y = 2¶

reference_frequency = 9¶

theta = 4¶

trace_1 = 10¶

trace_2 = 11¶

trace_3 = 12¶

trace_4 = 13¶

class ReferenceSlope(value)¶

An enumeration.

sine_zero = 0¶

ttl_falling = 2¶

ttl_rising = 1¶

class ReferenceSource(value)¶

An enumeration.

external = 2¶

internal = 0¶

internal_sweep = 1¶

class ReserveMode(value)¶

An enumeration.

manual = 1¶

maximum = 0¶

minimum = 2¶

class ScanMode(value)¶

An enumeration.

loop = 1¶

single_shot = 0¶

class ScanSampleRate(value)¶

An enumeration.

trigger = 14¶

x125mHz = 1¶

x128Hz = 11¶

x16Hz = 8¶

x1Hz = 4¶

x250mHz = 2¶

x256Hz = 12¶

x2Hz = 5¶

x32Hz = 9¶

x4Hz = 6¶

x500mHz = 3¶

x512Hz = 13¶

x62_5mHz = 0¶

x64Hz = 10¶

x8Hz = 7¶

class Sensitivity(value)¶

An enumeration.

x100mV_nA = 23¶

x100nV_fA = 5¶

x100uV_pA = 14¶

x10mV_nA = 20¶

x10nV_fA = 2¶

x10uV_pA = 11¶

x1V_uA = 26¶

x1mV_nA = 17¶

x1uV_pA = 8¶

x200mV_nA = 24¶

x200nV_fA = 6¶

x200uV_pA = 15¶

x20mV_nA = 21¶

x20nV_fA = 3¶

x20uV_pA = 12¶

x2mV_nA = 18¶

x2nV_fA = 0¶

x2uV_pA = 9¶

x500mV_nA = 25¶

x500nV_fA = 7¶

x500uV_pA = 16¶

x50mV_nA = 22¶

x50nV_fA = 4¶

x50uV_pA = 13¶

x5mV_nA = 19¶

x5nV_fA = 1¶

x5uV_pA = 10¶

class StatusByte(value)¶

An enumeration.

enabled_bit_in_LIA_status_set = 3¶

enabled_bit_in_error_status_set = 2¶

enabled_bit_in_standard_status_set = 5¶

no_command_execution_in_progress = 1¶

no_scan_in_progress = 0¶

output_buffer_non_empty = 4¶

service_request = 6¶

class Store(value)¶

An enumeration.

not_stored = 0¶

stored = 1¶

class SweepType(value)¶

An enumeration.

linear = 0¶

logarithmic = 1¶

class SynchronousFilter(value)¶

An enumeration.

off = 0¶

on = 1¶

class TimeConstant(value)¶

An enumeration.

x100ms = 8¶

x100s = 14¶

x100us = 2¶

x10ks = 18¶

x10ms = 6¶

x10s = 12¶

x10us = 0¶

x1ks = 16¶

x1ms = 4¶

x1s = 10¶

x300ms = 9¶

x300s = 15¶

x300us = 3¶

x30ks = 19¶

x30ms = 7¶

x30s = 13¶

x30us = 1¶

x3ks = 17¶

x3ms = 5¶

x3s = 11¶

class TraceNumber(value)¶

An enumeration.

four = 4¶

one = 1¶

three = 3¶

two = 2¶

class TriggerStartScanMode(value)¶

An enumeration.

no = 0¶

yes = 1¶

auto_gain()¶

Performs the auto-gain function.

Note that this function does not return until the process has completed.

auto_offset(offset_selector)¶

Automatically offsets the selected quadrature to zero

offset_selector should be of type OffsetSelector

auto_phase()¶: Performs the auto-phase function

auto_reserve()¶: Performs the auto-reserve function

clear_registers()¶: Clears all status registers, except for status enable registers.

close()¶

command_execution_in_progress()¶: Indicates if a command is currently being executed.

get_alarm_mode()¶: Returns whether the audible alarm is on or off.

get_aux_in(aux_in)¶

Returns the voltage of the specified auxiliary input.

aux_in should be of type AuxIn

get_ch1_output_source()¶: Returns the output source for channel 1.

get_ch2_output_source()¶: Returns the output source for channel 2.

get_current_gain()¶: Returns the conversion gain of the input current

get_detection_harmonic()¶: Returns the detection harmonic

get_frequency_sweep_type()¶

Returns whether a sweep is linear or logarithmic.

Returns type SweepType

get_input_configuration()¶: Returns the input configuration.

get_input_coupling()¶: Returns the input coupling mode

get_input_ground()¶: Returns the input shield grounding mode.

get_line_filter_status()¶: Returns the configuratin of the line filters

get_low_pass_slope()¶: Returns the slope of the low pass filter.

get_output_offsets_and_expands(offset_selector)¶

Returns the offsets and expands for the selected quadrature.

offset_selector should be of type OffsetSelector

get_reference_frequency()¶: Returns the frequency of the reference source

get_reference_phase()¶: Returns the phase shift of the reference source

get_reference_slope()¶: Returns the mode with wich the reference source is discriminated.

get_reference_source()¶

Returns the source used for the reference frequency.

Returns type ReferenceSource

get_reserve()¶: Returns the current value of the dynamic reserve.

get_reserve_mode()¶: Returns the reserve mode of the instrument.

get_scan_length()¶: Returns the scan length.

get_scan_mode()¶: Returns the scan mode.

get_scan_sample_rate()¶: Sets the sampling rate of a scan.

get_sensitivity()¶: Returns the sensitivity setting of the instrument

get_sine_amplitude()¶: Returns the amplitude of the sine output, in Volts.

get_start_frequency()¶: Returns the freqeuncy that a sweep starts at

get_stop_frequency()¶: Returns the frequency that a sweep stops at

get_synchronous_filter()¶: Returns the state of the synchronous filter.

get_time_constant()¶: Get the current time constant of the instrument.

get_trace(trace_number, points=None, units=None, binary=True)¶

Returns a vector of the values stored in the indicated trace

If get_trace times out while transferring data, the constants BINARY_TIME_PER_POINT and or ASCII_TIME_PER_POINT may need to be increased

Parameters

TraceNumber. (trace_number should be an element of) –
position (points is a list of two integers - the first indicates the) –
read (of the first value to be) –
number (while the second indicates the) –
default (of values to be read. By) –
read. (all points are) –
trace (units - string indicating the proper units of the) –
binary (binary - boolean indicating the method of data transfer. Using) –
faster. (is usually about 4 times) –

get_trace_definitions(trace)¶

Returns the definition of the given trace.

Trace should be an enumerator of Trace. The trace definition is of the form m1*m2/d

Returns

m1, m2 of type Multiply
d of type Divide
store of type Store

get_trigger_start_scan_mode()¶: Returns the mode in which the trigger initiates a scan.

pause_scan()¶

Pauses a scan or sweep.

Has no effect is no scans are in progress.

read_aux_input(aux_input)¶

Returns the value of the specified aux input

use type AuxInput

read_output(output_type)¶

Returns the value of the indicated output

use type OutputType.

read_simultaneously(parameters)¶

Returns simultaneously the values of the given parameters

the list parameters should have between two and six elements of the type Parameter

read_trace_value(trace_number, units=None)¶

Returns the current value of indicated trace

trace_number should be of enumeraror class TraceNumber. If specified, units are added to the returned value. units should be a string.

reset_scan()¶

Resets a scan.

This works whether a scan is in progress, finished, or paused. Note that the data buffer is erased.

scan_in_progress()¶

Indicates if a scan is in progress.

Note that a paused scan is counted as being in progress

set_alarm_mode(alarm_mode)¶

Sets the audible alarm on or off.

Use the enumerator AlarmMode.

set_ch1_output_source(ch1_output_source)¶

Sets the output source for channel 1.

Use the enumerator Ch1OutputSource.

set_ch2_output_source(ch2_output_source)¶

Sets the output source for channel 2

Use the enumerator Ch2OutputSource.

set_current_gain(current_gain)¶

Sets the conversion gain of the input current.

Use the enumerator CurrentGain

set_detection_harmonic(harmonic)¶: Sets the detection harmonic

set_frequency_sweep_type(sweep_type)¶

Sets whether a sweep is linear or logarithmic.

sweep_type should be of type SweepType

set_input_configuration(input_configuration)¶

Sets the input configuration.

input_conusing should be of type InputConfiguration

set_input_coupling(input_coupling)¶: Sets the input coupling mode Use the enumerator InputCoupling

set_input_ground(input_ground)¶

Sets the input shield grounding mode.

Use the enumerator InputGround

set_line_filter_status(line_filter)¶

Sets the configuration of the line filters.

Use the enumerator LineFilter

set_low_pass_slope(low_pass_slope)¶

Sets the slope for the low pass filter

Use the enumerator LowPassSlope

set_output_interface(rs232_interface=True)¶

Sets the output interface.

Default is serial (rs232_interface=True) Set rs232_interface to False for GPIB

set_output_offsets_and_expands(offset_selector, offset, expand)¶

Sets the offsets and expands for the selected quadrature.

offset_selector is of type OffsetSelector, and indicates which quadrature to use. Note that offset_selector should be in percent, and expand should be an integer between 1 and 256

set_reference_frequency(frequency)¶: Sets the frequency of the reference source

set_reference_phase(phase)¶: Sets the phase shift of the reference source

set_reference_slope(reference_slope)¶

Sets the mode with wich the reference source is discriminated.

This is only relevant when an external source is used.

reference_slope should be of type ReferenceSlope

set_reference_source(reference_source)¶

Sets the source used for the reference frequency.

reference_source should be of type ReferenceSource

set_reserve(reserve)¶

Sets the manual dynamic reserve.

Reserve should be an integer between 0 and 5, inclusive. 0 sets the minimum reserve for the current time constant and sensitivity. Each increment increases the reserve by 10dB.

set_reserve_mode(reserve_mode)¶

Sets the reserve mode of the instrument

Use the enumerator ReserveMode

set_scan_length(scan_length)¶: Sets the scan length.

set_scan_mode(scan_mode)¶: Sets the scan mode. Use the enumerator ScanMode.

set_scan_sample_rate(scan_sample_rate)¶

Sets the sampling rate of a scan.

Use the enumerator ScanSampleRate.

set_sensitivity(sensitivity)¶

Sets the sensitivity of the instrument.

Use the enumerator Sensitivity

set_sine_amplitude(amplitude)¶

Sets the amplitude of the sine output.

Must be between 0.004 and 5V. (Rounds to nearest 0.002 V)

set_start_frequency(frequency)¶: Sets the frequency a sweep starts at

set_stop_frequency(frequency)¶: Sets the frequency that a sweep stops at

set_synchronous_filter(synchronous_filter)¶

Sets the state of the synchronous filter.

Use the enumerator SynchronousFilter. Note that the synchronous filter only operates if the detection frequency is below 200Hz

set_time_constant(time_constant)¶

Sets the time constant of the instrument

Use the enumerator TimeConstant

set_trace_definitions(trace, m1, m2=Multiply.unity, d=Divide.unity, store=Store.stored)¶

Sets the definition of the given trace ‘trace’ to be m1*m2/d.

Trace should be an enumerator of Trace, m1 and m2 should be enumerators of Multiply, d should be an enumerator of Divide, and store should be an enumerator of Store.

set_trigger_start_scan_mode(trigger_start_scan_mode)¶

Sets the mode in which the trigger initiates a scan.

Use the enumerator TriggerStartScanMode.

start_scan()¶

Starts or resumes a scan/sweep.

Has no effect if a scan is already in progress.

trace_length(trace_number)¶

Returns the number of points in the specified trace

use the enumerator TraceNumber

trigger()¶: Initiates a trigger event.

class instrumental.drivers.lockins.sr850.ScanMode(value)¶

An enumeration.

loop = 1¶

single_shot = 0¶

class instrumental.drivers.lockins.sr850.ScanSampleRate(value)¶

An enumeration.

trigger = 14¶

x125mHz = 1¶

x128Hz = 11¶

x16Hz = 8¶

x1Hz = 4¶

x250mHz = 2¶

x256Hz = 12¶

x2Hz = 5¶

x32Hz = 9¶

x4Hz = 6¶

x500mHz = 3¶

x512Hz = 13¶

x62_5mHz = 0¶

x64Hz = 10¶

x8Hz = 7¶

class instrumental.drivers.lockins.sr850.Sensitivity(value)¶

An enumeration.

x100mV_nA = 23¶

x100nV_fA = 5¶

x100uV_pA = 14¶

x10mV_nA = 20¶

x10nV_fA = 2¶

x10uV_pA = 11¶

x1V_uA = 26¶

x1mV_nA = 17¶

x1uV_pA = 8¶

x200mV_nA = 24¶

x200nV_fA = 6¶

x200uV_pA = 15¶

x20mV_nA = 21¶

x20nV_fA = 3¶

x20uV_pA = 12¶

x2mV_nA = 18¶

x2nV_fA = 0¶

x2uV_pA = 9¶

x500mV_nA = 25¶

x500nV_fA = 7¶

x500uV_pA = 16¶

x50mV_nA = 22¶

x50nV_fA = 4¶

x50uV_pA = 13¶

x5mV_nA = 19¶

x5nV_fA = 1¶

x5uV_pA = 10¶

class instrumental.drivers.lockins.sr850.StatusByte(value)¶

An enumeration.

enabled_bit_in_LIA_status_set = 3¶

enabled_bit_in_error_status_set = 2¶

enabled_bit_in_standard_status_set = 5¶

no_command_execution_in_progress = 1¶

no_scan_in_progress = 0¶

output_buffer_non_empty = 4¶

service_request = 6¶

class instrumental.drivers.lockins.sr850.Store(value)¶

An enumeration.

not_stored = 0¶

stored = 1¶

class instrumental.drivers.lockins.sr850.SweepType(value)¶

An enumeration.

linear = 0¶

logarithmic = 1¶

class instrumental.drivers.lockins.sr850.SynchronousFilter(value)¶

An enumeration.

off = 0¶

on = 1¶

class instrumental.drivers.lockins.sr850.TimeConstant(value)¶

An enumeration.

x100ms = 8¶

x100s = 14¶

x100us = 2¶

x10ks = 18¶

x10ms = 6¶

x10s = 12¶

x10us = 0¶

x1ks = 16¶

x1ms = 4¶

x1s = 10¶

x300ms = 9¶

x300s = 15¶

x300us = 3¶

x30ks = 19¶

x30ms = 7¶

x30s = 13¶

x30us = 1¶

x3ks = 17¶

x3ms = 5¶

x3s = 11¶

class instrumental.drivers.lockins.sr850.TraceNumber(value)¶

An enumeration.

four = 4¶

one = 1¶

three = 3¶

two = 2¶

class instrumental.drivers.lockins.sr850.TriggerStartScanMode(value)¶

An enumeration.

no = 0¶

yes = 1¶