The ADA400A Differential Preamplifier allows direct oscilloscope measurements of very low amplitude voltages and signals which are not ground referenced. The high impedance of both inputs eliminates the need to add additional ground points in the DUT, thereby avoiding circulating currents which disturb the measurement or the circuit.

The high gain and extremely high common mode rejection provide usable measurements of voltages as low as 5 µV, even in high noise environments. Selectable bandwidth limiting reduces normal mode noise from digital logic, switch mode power supplies and line frequency sources. Adjustable differential offset allows the user to null out transducer bridge bias and galvanic potential from the test setup. An "infinite impedance" mode can be selected in the two highest gain ranges allowing accurate measurements of signals with high source impedance.

The ADA400A is powered directly from TDS400, TDS500, TDS600, TDS700, TDS5000, TDS7000 (TekProbe), TDS7000 (TekConnect w/TCA-1Meg) oscilloscopes. It may also be powered by a 1103 Probe Power Supply.

Includes: 070-9164-00 Instruction Manual, 159-0024-00 Spare Input Fuses (2).

Specifications

Gain: X100, X10, X1, X0.1

CMRR: >/=100,000:1 DC - 10 kHz

Bandwidth Limits: 100 Hz, 3 kHz, 100 kHz, Full (>/=1 MHz)

Input Impedance: 1 MΩ in parallel with approx. 50 pF (infinity Ω selectable in 100X and 10X gains)

Noise: Typically = 30 µV RMS @ X100 Gain (Referred to Input)

• Provides low level signal acquisition capability to scopes
• Low Pass Filters for 100 Hz, 3kHz, 100kHz, and Full (1 MHz)
• 10 µV/div Sensitivity.
• Typically 100 dB CMRR DC to 10 kHz
• Selectable Gain: 100,10,1, or 0.1
• No additional Power Supplies of cables required when used with TekProbe BNC scopes.