Good Will Instrument PSS-2005 User manual

PSS-3203/2005 PROGRAMMABLE POWER SUPPLY
USER MANUAL
i
Declaration of Conformity
We
GOOD WILL INSTRUMENT CO., LTD.
No. 95-11, Pao-Chung Rd., Hsin-Tien City, Taipei Hsien, Taiwan
declares that the below mentioned product
PSS-2005,PSS-3203
are herewith confirmed to comply with the requirements set out intheCouncilDirectiveon
the Approximation of the Law of Member States relating to Electromagnetic Compatibility
(89/366/EEC, 92/31/EEC, 93/68/EEC) and Low Voltage Equipment Directive
(73/23/EEC).
For the evaluation regarding the Electromagnetic Compatibility and Low Voltage
Equipment Directive, the following standards were applied:
◎EMC
EN 61326-1:Electrical equipment for measurement, control and laboratory use –– EMC
requirements(1997+A1: 1998)
Conducted and Radiated Emissions
EN 55011: 1991+A1:1997+A2:1996 ElectrostaticDischarge EN61000-4-2:1995
CurrentHarmonic
EN 61000-3-2: 1995+A1: 1998+A2:1998+A14:2000 Radiated Immunity EN 61000-4-3:1996
Voltage Fluctuation
EN 61000-3-3: 1995 Electrical Fast Transients EN 61000-4-4:1995
------------------------- Surge Immunity
EN 61000-4-5:1995
------------------------- Conducted Susceptibility
EN 61000-4-6:1996
------------------------- Voltage Dips/ Interrupts
EN 61000-4-11: 1994
◎Safety
Low Voltage Equipment Directive 73/23/EEC & amended by 93/68/EEC
EN61010-1: 1993+A2: 1995
IEC1010-1: 1990+A2: 1995
USA : UL 3111-1–First Edition, June 1994
Canada:CSA-C22.2 No. 1010.1-92

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CONTENTS PAGE
1.
PRODUCT INTRODUCTION................................................. 1-1. Description………………………………………………
1-
2. Feature…………………………………………………...
1
1
1
2. TECHNICAL SPECIFICATIONS…………………………
3
3. PRECAUTIONSBEFOREOPERATION…….…………...
3-1. Unpacking the Instrument……………….………….….
3-2. Checking the Line Voltage…………………..………….
3-3. Environment……………………………………..……...
5
5
5
6
4. PANEL INTRODUCTION……………………..…………...
7
5. OPERATION METHOD………………………………...….
5-1. Output Voltage/Current Setting…………………..……
5-2. Over Voltage/Current Protection Setting… …………...
5-3. The Display Contrast Setting.…………………………..
5-4. The Buzzer Setting………………………………………
5-5. GPIB/RS-232 Interface Setting…………………………
5-6. The Maximum Setting Value…………………………...
5-7. Test Lead………………………………………………...
5-8. The Setting for the GPIB and RS232 Interface………..
10
10
11
12
12
12
13
13
13
6. MAINTENANCE………………………..…………………..
6-1. Fuse Replacement……………………………………….
6-2. Line Voltage Conversion………………………………..
6-3. Adjustment and Calibration……………………………
6-4. Cleaning…………………………………………………
14
14
14
15
18
7.THE SYSTEM DIAGRAM AND DESCRIPTION………..
7-1.Block Diagram…………………………………………...
7-2.The Operation of the whole circuit……………………...
19
19
20

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SAFETY TERMS AND SYMBOLS
These terms may appear in this manual or on the product:
WARNING. Warning statements identify condition or
practices that could result in injury or loss of life.
CAUTION. Caution statements identify conditions or
practices that could result in damage to this product or
other property.
The following symbols may appear in this manual or on the product:
DANGER ATTENTION Protective Earth(ground) FrameorChassis
High Voltage refer to Manual Conductor Terminal Terminal
Terminal
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FOR UNITED KINGDOM ONLY
NOTE: This lead/appliance must only be wired by competent persons
WARNING: THIS APPLIANCE MUST BE EARTHED
IMPORTANT: The wires in this lead are coloured in accordance with
the following code:
Green/ Yellow: Earth
Blue: Neutral
Brown: Live (Phase)
As the colours of the wires in main leads may not correspond with the
colours marking identified in your plug/appliance, proceed asfollows:
The wire which is coloured Green & Yellow must be connected to the
Earth terminal marked with the letter E or by the earth symbol
or coloured Green or Green & Yellow.
The wire which is coloured Blue must be connected to the terminal
which is marked with the letter N or coloured Blue or Black.
The wire which is coloured Brown must be connected to the terminal
marked with the letter L or P or coloured Brown or Red.
If in doubt, consult the instructions provided with the equipment or
contact the supplier.

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This cable/appliance should be protected by a suitably rated and
approved HBC mains fuse: refer to the rating information on the
equipment and/or user instructions for details. As a guide, cable of
0.75mm2should be protected by a 3A or 5A fuse. Larger conductors
would normally require 13A types, depending on the connection
method used.
Any moulded mains connector that requires removal /replacement
must be destroyed by removal of any fuse & fuse carrier and disposed
of immediately, as a plug with bared wires is hazardous if a engaged
in live socket. Any re-wiring must be carried out in accordance with
the information detailed on this label.
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1. PRODUCT INTRODUCTION
1-1.Description
PSS-series Programmable Power Supply is controlled by Micro
Processor Unit (MPU) that can easily connect communication interface
RS-232 or GPIB to computer in order to satisfy users’ demand for
auto-testing and auto-control.
The voltage and current are completely controlled by a 12 bits D/A
Converter with higher resolution and accuracy. Also, the digitalization of
system makes a speedy, precise and convenient input of information
controlled by keyboard and wheel knob.
The adjustment of voltage/current is made by software calibration
without man-made error that will increase the preciseness of the
instrument.
The function of Over Voltage Protection (OVP) and Over Current
Protection (OCP) is set with software and detected with hardware to
achieve protected function precisely and speedily in order to secure users
from danger by using the instrument.
1-2. Feature
1) An overall digitalization of programmable interface with high
resolution.
2) The 16×2LCD Display.
3) High stability and low draft.
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4) The function of over voltage/current/temperature protection.
5) Intelligent control fan (Vary with different output power.)
6) Warning signal by the built-in Buzzer.
7) Step by step calibration procedure.
8) Brand new panel design and the 1/4 rack size reduction volume
design.
9) Wheel knob of Fine and Coarse.
10)IEEE-488.2 and SCPI compatible command setting.
11)Correspond to UL, CSA, CE, and LVD safety regulation.

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2.TECHNICAL SPECIFICATIONS
SPECIFICATIONS PSS-3203 PSS-2005
Voltage 0~32V×10~20V×1
Current 0~3A×10~5A×1Output OVP 0~33V×10~21V×1
Voltage ≦3mV(≦5mV rating current>3.0A)
Load Effect Current ≦3mA(≦5mA rating current>3.0A)
Voltage ≦3mV
Source Effect Current ≦3mA
Voltage 10mV(20mV rating voltage>36V)
Current 1mA(2mA rating current>3.5A)
Resolution OVP 10mV(20mV rating voltage>36V)
Voltage ≦0.05%+10mV(+20mV rating voltage>36V)
Current ≦0.1%+5mA(+10mAratingvoltage>3.0A)
Program
Accuracy
(25±5℃)OVP ≦0.05%+10mV(+20mV rating voltage>36V)
Voltage Ripple≦1mVrms/3mVp-p
Noise≦2mVrms/30mVp-p
Ripple & Noise
(20Hz~20MHz)
Current ≦3mArms (≦5mArms rating current>3.0A)
Voltage ≦100ppm+3mV Temperature
Coefficient
(0~40℃)Current ≦100ppm+3mA
Voltage 10mV(20mV rating voltage >36V)Readback
Resolution Current 1mA(2mA rating current >3.0A)
Voltage ≦0.05%+10mV(20mV rating voltage >36V) Readback
Accuracy
(25±5℃)Current ≦0.1%+5mA(10mA rating current >3.0A)
10%~90%
≦100ms
Response Time
Voltage Up
Voltage Down 90%~10% ≦100ms (≧10% rating load)
Voltage ≦100ppm+10mV(+20mV rating voltage>36V) Readback
Temperature
Coefficient Current ≦100ppm+5mA
Voltage ≦100ppm+10mV(+20mV rating voltage>36V)
Drift Current ≦150ppm+10mA
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Interface RS232, GPIB interface option
Power Source AC100V, 120V, 220V±10%, 230V +10%/-6% 50/60Hz.
Dimensions 110(W)×140(H)×320(D) mm. Mechanical
Spec. Weights 4.8kg
Operation
Environmental
Indoor use
Altitude up to 2000 m
Ambient temperature :
To satisfy specifications : 10℃to 35℃( 50°F to 95°F )
Maximum operating ranges: 0℃to 40℃( 32°F to 104°F )
Relative humidity: 85% RH(max.) non condensing
Installation Category : II
Pollution degree 2
Storage
Temperature &
Humidity -10°to 70℃, 70%RH (maximum)
Accessories Power cord….............……….. 1 Instruction manual…………… 1
Test Lead……….……………. 1

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3.PRECAUTIONS BEFORE OPERATION
3-1.Unpacking the Instrument
The product has been fully inspected and tested before shipping from the
factory. Upon receiving the instrument, please unpack and inspect it to
check if there is any damage caused during transportation. If any sign of
damage is found, notify the bearer and/or the dealer immediately.
3-2.Checking the Line Voltage
The product can be applied by any kind of line voltages shown in the table
below. Before connecting the power plug to an AC line outlet, make sure
the voltage selector of the rear panel is set to the correct position
corresponding to the line voltage. It might be damaged the instrument by
connecting to the wrong AC line voltage.
WARNING. To avoid electrical shock the power cord
protective grounding conductor must be connected to
ground.
AVERISS: Pour éviter les chocs électriques, le fil de terre
du cordon secteur doit impérativement être relié à la
terre.
When line voltages are changed, replace the required fuses shown as below:
Model Line
voltage
Range Fuse
Line
voltage
Range Fuse
PSS-3203
T3A
250V
T1.6A
250V
PSS-2005
100V
120V
90-110V
108-132V
T3A
250V
220V
230V
198-242V
216-253V
1.6A
250V
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WARNING. To avoid personal injury, disconnect the power cord
before removing the fuse holder.
3-3.Environment
The normal ambient temperature range of this instrument is from 0°to 40°C
(32°to 104°F). To operate the instrument exceeding this specific
temperature range may cause damage to the circuits of instrument.
Do not use the instrument in a place where strong magnetic or electric field
exists as it may disturb the measurement.

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4. PANEL INTRODUCTION
POWER
OUTPUT
4
3
5
9
8
7
10
F C
SETVSETI
ENTER
0 32V 0 3A
OUTPUT
CV 33 .00V 0 .000 A
LOCAL
MENU
OUT
6
11
2
1
PSS-3203
R PROGRAMMABLE
POWER SUPPLY
Figure 4-1 Front Panel
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BEFORE REPLACING FUSEDISCONNECT POWER CORD AS SPECIFIED
REPLACE FUSE
12
220V
120V 250V
100V
FUSE RATING
250V 50/60 Hz
AC
230V
190 WATTS
235 VA
T 3A
T 1.6A
15
GPIB
230V100V 120V 220V
AC SELECTOR
13
ETL LABEL
14
Figure 4-2 Rear Panel

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1. Power Switch Connect the AC power, then press power switch.
2. Display Indicate the s
etting of voltage/current value, output
voltage/current value and the status of setting and
output.
3. +Output Terminal Positive output terminal.
4. -Output Terminal Negative output terminal.
5. GND Terminal Connect the ground terminal to chassis.
6. Rotary Encoder Wheel knob.
7. V Set/I Set
(ENTER) The key for switch over output voltage and output current setting.
ENTER: The knob for value input or setting
confirmation.
8. F/C
The knob for switching over coarse and fine
adjustment.
9. MENU The c
ategory of function setting (Output, OVP,
OCP, Contrast, Buzzer, Interface.)
PS. After switching to the picture of function
setting category, if there is no further setting action
within 4 to 5 seconds, the system will return to
previous setting picture oroutput display picture.
10. LOCAL
Clear REMOTE control mode, and replace with
panel control.
PS. Get into calibration mode by pressing the knob
more than 5 seconds uninterruptedly,
11. Output Turn on or off output by pressing the knob.
12. AC Power Socket AC power input terminal.
13. AC Select Switch
Switch Voltage to 100V, 120V, 220V or 230V,
50/60Hz.
14. Cooling Fan A cooling fan.
15 Interface GPIB or RS-232C communication interface.

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5. OPERATION METHOD
5-1. Output Voltage/Current Setting
At first, ensure that the window now is at the Output Voltage/
Current setting or the output value display.
or
--Output Voltage Setting:
Press [Vset/Iset] to set the cursor to the position for voltage input,
and modify the setting value with wheel knob. Right now, can use
[F/C] to switch over the input of 1V step or 10mV step.
Example:
If want to set the voltage as 12.34V, first using the [F/C] knob to
switch the cursor to 10mV step and adjust the value to 34, then
switch the cursor to 1V step and adjust the value to 12 to complete
the modification.
>>
>>
PS. If the output is on now, the output voltage value will be varied
with the setting of the knob.
--Output Current Setting:
After pressing [Vset/Iset] to set the cursor to the position for
current input, modify the setting value with wheel knob. Right now,
use [F/C] to switch over the input of 100mA step or 1mA step.
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Example:
If want to set the current as 1.234A, first using the [F/C] knob to
switch the cursor to 1mA step and adjust the value to 34, then
switch the cursor to 100mA step and adjust the value to 12 to
complete the modification.
>>
>>
Note: 1. When the load current through output terminal exceeds
the setting value, the instrument is operated in the C.C.
mode, if not exceeds the setting value, the instrument is
operated in the C.V. mode.
2. When the maximum output voltage is larger than 36V, its
adjustable step is 20mV the minimum while the
maximum output current is larger 3A, its adjustable step
is 2mA the minimum.
5-2.Over Voltage /Current Protection Setting
--Over Voltage Protection Setting:
Set to OVP SET window by pressing [MENU], modify the setting
value with the wheel knob and press [ENTER]. The modification
can be done by using the [F/C] knob to switch over the input of
1V step or 10mV step.
--OVP Status Clear Up:
When the output voltage exceeds the setting voltage, the output of
the instrument will be off and get into OVP mode by displaying
“OVP Error. Press “LOCAL” to reset” on the panel. Just press
[LOCAL] to clear OVP status and back to previous status.

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--Over Current Protection Setting:
Set to OCP SET window by pressing [MENU], Turn on/off the
OCP with the wheel knob and press [ENTER]. If OCP is on, when
the output current equals or exceeds the current value setting, the
output of the instrument will be off and get into over current
protection mode by displaying “OCP Error. Press “LOCAL” to
reset” on the display.Just press [LOCAL] to clear OCP status and
back to previous status.
5-3. The Display Contrast Setting
Set to Contrast Set window by pressing [MENU], modify its setting
value with the wheel knob and press [ENTER].
5-4. The Buzzer Setting
Set to Buzzer Set window by pressing [MENU], turn on or off the
buzzer with the wheel knob, then press [ENTER].
5-5.GPIB/RS232 Interface Setting
Set to Interface window by pressing [MENU]. If the GPIB is
displayed, the Address value window will be appeared, if the
RS-232 is displayed, the Baud Rate window will be appeared, then
using the wheel knob to modify the value and press [ENTER] to
complete the setting.
Note: The system will detect the interface used at present
automatically, and switch the detected interface over the
setting interface of GPIB or RS-232.
Example:
1) If want to set the GPIB address value to 15:
Set to interface window by pressing [MENU], and adjust the
address value to 15 with the wheel knob and press [ENTER] to
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complete the setting.
2) If want to set the RS-232 Baud Rate to 9600:
Set to interface window by pressing [MENU], and adjust the
Baud Rate value to 9600 with the wheel knob and press [ENTER]
to complete the setting.
5-6. The Maximum Setting Value
MODEL
ITEM PSS-3203 PSS-2005
Output Voltage 33.00V 21.00V
Output Current 3.100A 5.200A
Over-voltage 34.00V 22.00V
5-7.Test Lead
MODEL
ITEM PSS-3203 PSS-2005
Current 3A
Test Lead Current 4A-10A Test Lead
5-8. The setting for the GPIB and RS232 Interface
If you have PSS-series programmable power supply, use the GPIB
or RS-232 interface, please refer to the PSS-series Programmer
Manual for more details.

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6. MAINTENANCE
The following instructions are executed by qualified personnel only.
To avoid electrical shock, do no perform any servicing other than the
operating instructions unless you are qualified to do so.
Warning: Do not remove covers. Refer servicing to qualified
personnel.
AVERTISS: Ne pas enlever le capot. Seul un personnel habilité
peut intervenir sur le matériel.
Warning: No operator serviceable components inside.
AVERTISS:Pas de maintenance sur les composants internes.
6-1.Fuse Replacement
If the fuse blows, the display will not light and the power supply will
not operate. The fuse should not normally open unless a problem has
developed in the unit. Try to determine and correct the cause of the
blown fuse, then replace only with a fuse of the correct rating and
type (refer to 3-2 of page 5). The fuse is located on the rear panel
(see Fig.4-2).
WARNING. For continued fire protection. Replace
fuse only with 250V fuse of the specific type and rating,
and disconnect power cord before replacing fuse.
AVERTISS: Pour une protection contre les risques d’incendie,
remplacer le fusible exclusivement par un modèle aux
caractéristiques équivalentes.
WARNING
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6-2. Line Voltage Conversion
The primary winding of the power transformer is tapped to permit
operation from 100, 120, 220, or 230VAC, 50/60 Hz line voltage.
Conversion from one line voltage to another is done by change AC
selects switch. The rear panel identifies the line voltage to which the
unit was factory set. To convert to a different line voltage, perform
the following procedure:
(1) Make sure the power cord is unplugged.
(2) Change the AC selects switch to the desired line voltage
position.
(3) A change in line voltage may also require a corresponding
change of fuse value. Install the correct fuse value as listed on
rear panel.
6-3. ADJUSTMENT AND CALIBRATION
--Preparation
(1) 30 minutes warm up before calibration.
(2) Ambient temperature:23±5°C, Humidity: Under PH80%.
--Output Calibration Steps:
[Step 1]
Press [LOCAL] for 4 to 5 seconds interruptedly to appear Password
input window (vary with different models: PSS-3203: 3203,
PSS-2005: 2005), input the password number with the wheel knob,
and use the F/C button to shift the input position at the same time,
then press [ENTER]. When the password number has been input by
mistake, the system will jump out of the present mode.

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[Step 2] Voltage Calibration Step
After getting into Calibration selection window, select Voltage
calibration with the knob and press [ENTER].
[Step 2.1]
Now input the voltage value (Min) measured by DMM with the knob
and press [ENTER]. During the voltage value input, use the [F/C]
button to switch over the input of 1V step or 10mV step.
Note: The DMM selected for the measurement have the resolution of
three digits of the decimal point at least (1mV). Also the input value
is to take two digits of decimal point of effective value (10mV) and
run off the rest.
[Step 2.3]
Adjust VR311 and adjust the voltage value measured by DMM
according to the voltage displayed in the window, then press
[ENTER].
Note: The DMM selected for the measurement must have the
resolution of three digits of the decimal point at least (1mV).
During the adjustment, the maximum error of the measured
value is ±0.005V.
[Step 3] Current Calibration Steps
Switch the Calibration selection window to current calibration item
with the knob and press [ENTER] getting into current calibration

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steps.
[Step 3.1]
Now input the current value (Max.) measured by the DMM with the
knob and press [ENTER]. During the current value input, use the
[F/C] button to switch over the input of 100mA range (100mA/step)
or 1mA range (1mA/step).
Note: The DMM selected for the measurement must have the
resolution of four digits of the decimal point at least (0.1mA).
Also the input value is to take three digits of decimal point of
effective value (1mA) and run off the rest.
[Step 3.2]
Now input the current value (Min.) measured by the DMM with the
knob and press [ENTER]. During the current value input, use the
[F/C] button to switch over the input of 100mA range (100mA/step)
or 1mA range (1mA/step).
Note:The DMM selected for the measurement must have the
resolution of four digits of the decimal point at least (0.1mA).
Also the input value is to take three digits of decimal point of
effective value (1mA) and run off the rest.
[Step 4]
Switch the Calibration selection window to O.V.P. calibration item
with the knob and press [ENTER] getting into O.V.P calibration
steps.
[Step 4.1]
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At present, the window will indicate the progress of OVP calibration.
When the calibration is completed, it will jump out of the window.
[Step 5]
When above calibration steps has been confirmed correctly, switch
the calibration selection window to SAVE window with the knob and
press [ENTER] to complete the whole calibration procedures.
[Step 6]
If the calibration procedure is not necessary to be stored, just switch
the calibration selection window to Exit window and press [ENTER]
to leave the calibration procedure.
6-4. Cleaning
To clean the power supply, use a soft cloth dampened in a solution
of mild detergent and water. Do not spray cleaner directly onto the
instrument, since it may leak into the cabinet and cause damage. Do
not use chemicals containing benzine, benzene, toluene, xylene,
acetone, or similar solvents. Do not use abrasivecleaners on any
portion of the instrument.

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7. THE SYSTEM DIAGRAM AND DESCRIPTION
7-1. Block Diagram
The graph above is the system diagram of PSS-SERIES, Which consists
of Micro Processor Unit (MPU), Digital to Analog Converter (DAC),
Analog Switch Circuit, Reference Voltage Circuit, Driver Circuit,
Control Circuit, Comparator, and etc.
AC
INPUT TRANSFORMER RELAY CONTROL
VOLTAGE
COMPARATOR
CURRENT
COMPARATOR
D TO A
CONVERTER
REFERENCE
ANALOG
SWITCH
AND SAMPLE
HOLD
MICRO
CONTROL
LCM
DISPLAY
KEYBOARD
AUX
RECTIFIER
AND FILTER
SERIES
REGULATOR
AMPLIFIER
OR
GATE
O/P
INTERFACE
RS-232 OR GPIB
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7-2.The Operation of the whole circuit
Each output channel of PSS-series has a reference voltage circuit at
around 2.5V output voltage which can be amplified to 2.5 (1+R314
/(R315+Vr))=2.5(1+12.4K/(7.68K+Vr)) by a non-inverter amplifier.
When Vr=0~500, take its middle value to convert above formula into
6.41V, and treat this as the reference voltage of DAC AD7541. The
AD7541 is a 12-bit DAC with 6.41V/4095=1.56mV/bit of the resolution.
When the instrument is in C.V. Mode, the MPU will send 3300
counts, 33.00V of output voltage, to DAC, output through analog switch
and Sample Hold circuit, the voltage now is at around
-5.148V(-1.56mVx3300=-5.148V). Then, compare this voltage with the
real output voltage which is retrieved by the voltage sense circuit. As the
entire circuit is a close loop, therefore, the retrieved voltage value will be
followed with the reference voltage of Sample Hold. Besides, the
Comparator output terminal will output a related voltage value to control
the whole output circuit through a driver circuit?and generate the
required output voltage. The attenuation of the voltage sense circuit is
A=R342/(R342+R335)=4.99K/(4.99K+27.0K) =0.156, and the output
voltage is Vout=5.148/A=5.148/0.156=33.00V?If the output is affected
by the offset of materials, can use the Vr to make adequate adjustment.

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The operation in C.C. Mode is similar to that in C.V. Mode. The
MPU will send 2100 counts, 2.1A output current, to DAC, output
through analog switch and Sample Hold circuit, the voltage now is at
around -3.276V (-1.56mVx2100=-3.276V). Then, compare this voltage
with the real output voltage which is retrieved by the current sense
circuit. As the entire circuit is a close loop, therefore, the retrieved
voltage value will be followed with the reference voltage of Sample Hold.
Besides, the Comparator output terminal will output a relative voltage
value to control the whole output circuit through a driver circuit?and
generate the required output voltage. The current sense circuit for
detecting the voltage value from current sense resistor is mainly
composed by differential amplifier TL071. The multiple of the
differential amplifier is A=-R355/R356=-22.0K/1.91K=-11.518, the
voltage on the both sides of current sense resistor is
-3.276/-11.518=0.285V, so the output current is basis on
Iout=(0.285/R374)*2=(0.285/0.3)*2=1.9A, and 2.1A making multiple
operand to get a real output current by using the software.
The Displayed Value of Voltage and Current
The voltage/current sense circuit retrieves a voltage value which will
be sent to Comparator through Analog Switch, and joined with the output
voltage of DAC in dichotomy approaching method to get the same
voltage as the real output value of the instrument.
PSS-3203/2005 PROGRAMMABLE POWER SUPPLY
USER MANUAL
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