Picotest.com, has released a new solid-state Semi-Floating Amplifier (SFA), or ground loop isolator, that provides the BEST isolation for low impedance measurements. The new amplifier eliminates the DC ground loop from DC up to 800MHz. The high frequency response supports the 2 Port Shunt Thru impedance measurement required for Power Distribution Networks (PDNs). The amplifier works with network analyzers and oscilloscopes.

The J2113A removes the ground loops associated with VNAs and Oscilloscopes which frequently occur in power integrity PDN measurements. The existence of the ground loops can be hidden and can impact the measurement results dramatically if not accounted for. The J2113A’s frequency response is flat from DC to over 800MHz, all while maintaining 50Ohm input impedance for accurate, low-noise measurements. It allows measurement both lower and higher in frequency than achievable with a passive common mode transformer. The J2113A supports power distribution network (PDN) measurement, component measurement, PSRR testing and many other applications.

The introductory price of the J2113A is $1500 in single quantities and is available now from www.Picotest.com. https://www.picotest.com/products_J2113A.html. The J2113A is CE certified and is available for immediate delivery.

Selected Specifications:

  • Recommended Bandwidth          DC-800 MHz (-3dB), DC-700MHz (-1dB)
  • CMRR                                            > 57dB
  • Maximum Voltage                        1.9V
  • Input/Output Impedance              50 ohms

J2113A semi-floating differential amplifier is used to eliminate ground loop created by certain instrumentation setups like the PSRR measurement used in power supply tests and the 2-port shut thru impedance measurement used in power integrity applications.

The J2113A semi-floating differential amplifier is used to break the instrumentation ground loop in this 2 port shunt thru impedance test setup of a decoupling capacitor using the Bode 100 VNA.

Comparison plot using the active J2113A Semi-Floating Differential Amplifier (Red), passive J1202A coaxial transformer (Blue), and no ground loop compensating device (Green). Measurement is of a 1mOhm resistor with the J2102A, the J2113A and no ground loop breaker.

S21, S11, and S22 plots show the 3dB performance of the J2113A. S21 -3dB bandwidth @ 830MHz and S22 -6dB bandwidth @ 635 MHz.

2-port shunt thru

Typical 2-port shunt thru transfer impedance measurement setup showing the DUT, the VNA ports, and the required semi-floating differential amplifier/ground loop breaker. Photo courtesy R&D Altanova, http://rdaltanova.com/.

For more information, please visit www.Picotest.com.