

Key Features
Overview
Why Engineers Choose The Injecteur PSRR à tension négative Picotest J2123A
Dual-Supply System Testing
Audio Amplifier Validation
Precision Reference Circuits
Frequently Asked Questions
Have a Question?
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Is the J2123A suitable for production testing environments?
Absolutely. The passive design ensures reliability, whilst the wide frequency range covers most product requirements. The device withstands repeated use and provides consistent measurements essential for production quality control.
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What test equipment do I need in addition to the J2123A?
A network analyser or signal generator for modulation, a negative voltage power supply, and appropriate cables. Optional equipment includes current probes for impedance measurements and the remote sense board for improved voltage regulation.
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How does the J2123A compare to using injection transformers?
The J2123A handles DC current without saturation, unlike injection transformers which fail with even small DC currents (5mA or less). This makes the J2123A essential for PSRR measurements where injection transformers would be damaged or provide inaccurate results.
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What safety precautions should I observe when using the J2123A?
Never exceed the absolute maximum ratings: -50V DC+AC combined, 3A continuous current, and 50°C operating temperature. Ensure proper grounding and use appropriate personal protective equipment when working with high voltages.
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Can I measure input impedance with the J2123A?
Yes, when used with a current probe, the J2123A enables input impedance measurements of negative voltage power supplies and DC-DC converters. This is particularly useful for stability analysis and EMI filter design in negative voltage systems.
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What modulation sources work with the J2123A?
Any network analyser or signal generator with appropriate output level. The J2123A accepts -20dBm to +10dBm signals through its 10kΩ input impedance. Popular choices include the OMICRON Lab Bode 100, Keysight E5061B, and Rohde & Schwarz ZNB series.
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How do I compensate for the voltage drop across the J2123A?
Use remote sensing if your power supply supports it, or manually adjust the supply voltage to account for the drop. The voltage drop follows V(I) = 2.312 × I^0.055 + 0.090I. Alternatively, use the optional remote sense board for automatic compensation.
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What happens if I connect the polarity incorrectly?
The J2123A contains a polarised internal capacitor that will be permanently damaged by reverse voltage. Always verify that the return jack (ground) is more positive than the MINUS SUPPLY connection before applying power.
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Can I use the J2123A with standard laboratory power supplies?
Yes, but ensure correct polarity connections. The ground terminal should be more positive than the negative supply terminal. Many power supplies can be configured for negative output by reversing their connections, making them compatible with the J2123A.
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What makes the J2123A different from the J2120A line injector?
The J2123A is specifically designed for negative voltage systems with polarised internal components, whilst the J2120A handles positive voltages. The J2123A has lower current capacity (3A vs 5A) but identical frequency response, making it ideal for lower-power negative rail applications.