1ch Low Power Current Source

Introduction

The WPC 1ch Low Power Current Source (LPCS) is a signal processing front-end module that converts voltage signals into high-precision, minute current outputs. This product is designed for applications requiring precise current drive and measurement, featuring a compact size and efficient current control capabilities.

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Specifications

Parameter	Min.	Typ.	Max.	Unit	Condition/Description
Current Source Power Input (Vcs)	5	9	12	V	-
Amplifier Power Input (Vcc)	7	12	15	V	Must be at least 2V higher than Vcs
Voltage Input Range (Vin)	0		5	V	Vcs = 12V
Voltage Input Threshold (Vth)	20	40	50	mV	-
Current Output Range (Iout)	0		200	mA	Vcs = 12V
Current Output Precision	5		10	µA	-
Vsens Output Range	10		12	V	Must be less than Vcc-2V (Vcc=±15V)
Isens Output Range	10		12	V	Vcc = ±15V

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Hardware Interface and Pinout

The WPC 1ch LPCS features two sets of terminals (top and bottom), responsible for connecting different signals and power supplies:

Top Terminals (Pin 1 ~ 10)

Mainly responsible for power input and control signal connections.

Pin Number	Description	Function Description
1	Current source power in+	Current source positive power input (Vcs)
2	Current source power in+	Current source positive power input (Vcs)
3	Sense amplifier power in+	Sense amplifier positive power (Vcc)
4	Sense amplifier power in-	Sense amplifier negative power
5	Current Control Voltage in+	External control voltage input (Vin)
6	AGND	Analog Ground
7	Current sense voltage out+	Current sense voltage output (Isens)
8	AGND	Analog Ground
9	Voltage sense voltage out+	Voltage sense voltage output (Vsens)
10	AGND	Analog Ground

Bottom Terminals (Pin 1 ~ 4)

Mainly responsible for current output and load-end voltage sensing.

Pin Number	Description	Function Description
1	Vsens-	Voltage sense (Neg.)
2	Iout-	Current output (Neg.)
3	Iout+	Current output (Pos.)
4	Vsens+	Voltage sense (Pos.)

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System Connection and Applications

System Connection Example

Example of connection for control and measurement using a general data acquisition device (DAQ):

Application Example: Contact Resistance Measurement

tip

To measure contact resistance, it is strongly recommended to use 4-wire sensing technology to eliminate errors caused by the impedance of the wires themselves, ensuring the precision of the measurement results.

Characteristic Curve: Input Voltage vs. Output Current

The figure below shows the linear relationship curve between the control input voltage and the corresponding output current:

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Extension Module: 2ch Power LPCS (Dedicated Power Supply)

The WPC 2ch Power LPCS is a high-isolation dual-channel power supply specifically designed to drive the WPC 1ch LPCS, effectively simplifying system wiring and enhancing signal stability.

Product Specifications and Features

• Supported Devices: Can simultaneously support 2 sets of WPC 1ch LPCS
• Power Input (Power In): 24 VDC
• Power Output (Power Out): ±12 V Highly Isolated
• Current Output Control (Current Out Control): 0 ~ 5 V
• Voltage / Current Sense: 0 ~ 5 V

Front Panel Interface

The front panel features two sets of output ports, which can be connected directly via 4-pin signal cables to the bottom terminals of the 1ch LPCS.

Pin Number	Description
1	Vsens-
2	Iout-
3	Iout+
4	Vsens+

Rear Panel Interface

The rear panel features two sets of 10-pin box headers (IDC-10P) and signal interfaces for connecting to the DAQ, divided into two independent channels, Channel A and Channel B.

Pin Number	Channel	Description	Function Description
1	A	Vsens	Voltage sense (0 ~ 10V output)
2	A	Isens	Current sense (0 ~ 10V output)
3	A	Ictrl	Current control (0 ~ 5V input)
4	A	GND	Channel A dedicated Analog Ground (AGND)
5	B	Vsens	Voltage sense (0 ~ 10V output)
6	B	Isens	Current sense (0 ~ 10V output)
7	B	Ictrl	Current control (0 ~ 5V input)
8	B	GND	Channel B dedicated Analog Ground (AGND)