The Tektronix ADA400A is a high-gain, differential preamplifier designed to extend the sensitivity and common-mode rejection capabilities of compatible Tektronix oscilloscopes. It provides differential measurements from high-impedance sources and features selectable gain settings from 0.1X to 100X, customizable bandwidth limiting, and exceptionally high common-mode rejection, making it ideal for low-amplitude measurements in noisy environments.
Specifications
General
| Parameter | Value |
|---|---|
| Interfaces | TekProbe BNC (output interface), 2 x Standard BNC (input interfaces) |
| Display | LED status indicators for Gain, Bandwidth, and Input Coupling |
Physical
| Parameter | Value |
|---|---|
| Power Supply | Powered directly from the host oscilloscope via TekProbe BNC interface, or via external 1103 TekProbe Power Supply |
| Operating Temperature | 0 to 50 |
| Dimensions (W×H×D) | 32 mm × 76 mm × 135 mm |
| Weight | 0.36 |
Signal & Amplification Performance
| Parameter | Value |
|---|---|
| Bandwidth | DC to 1 MHz |
| Selectable Gain Settings | 0.1X, 1X, 10X, 100X |
| Gain Accuracy | ±2% (at DC) |
Common-Mode Rejection Ratio (CMRR)
| Parameter | Value |
|---|---|
| CMRR at 60 Hz (100X Gain) | ≥ 100,000:1 (100 dB) |
| CMRR at 60 Hz (10X Gain) | ≥ 100,000:1 (100 dB) |
| CMRR at 60 Hz (1X Gain) | ≥ 10,000:1 (80 dB) |
| CMRR at 60 Hz (0.1X Gain) | ≥ 10,000:1 (80 dB) |
Input Characteristics
| Parameter | Value |
|---|---|
| Input Configuration | Differential (A - B) |
| Input Resistance (100X and 10X Gain) | 1 MΩ or >10^12 Ω (selectable) |
| Input Resistance (1X and 0.1X Gain) | 1 MΩ (fixed) |
| Input Coupling Modes | AC, GND, DC (independently selectable for Channel A and Channel B) |
| Maximum Differential Input Voltage (100X Gain) | ±10 mV |
| Maximum Differential Input Voltage (10X Gain) | ±100 mV |
| Maximum Differential Input Voltage (1X Gain) | ±1 V |
| Maximum Differential Input Voltage (0.1X Gain) | ±10 V |
| Maximum Common-Mode Input Voltage (100X and 10X Gain) | ±10 V |
| Maximum Common-Mode Input Voltage (1X and 0.1X Gain) | ±40 V |
| Maximum Non-Destruct Input Voltage | ±40 V (DC + peak AC) |
| DC Offset Adjust Range (100X Gain) | ±10 mV (referred to input) |
| DC Offset Adjust Range (10X Gain) | ±100 mV (referred to input) |
| DC Offset Adjust Range (1X Gain) | ±1 V (referred to input) |
| DC Offset Adjust Range (0.1X Gain) | ±10 V (referred to input) |
| DC Offset Adjustment Controls | Multi-turn screwdriver-adjustable coarse and fine potentiometers on the side panel |
| Input Capacitance (100X and 10X Gain) | 125 pF |
| Input Capacitance (1X and 0.1X Gain) | 10 pF |
| Input Bias Current (100X and 10X Gain) | ≤ 9 nA |
| Input Offset Current (100X and 10X Gain) | ≤ 4 nA |
Bandwidth Limiting & Filtering
| Parameter | Value |
|---|---|
| Low-Pass Filter Settings | 100 Hz, 3 kHz, 100 kHz, FULL (1 MHz) |
| Low-Pass Filter Roll-off Rate | 20 dB/decade (single-pole) |
Output Characteristics
| Parameter | Value |
|---|---|
| Output Impedance | 50 Ω |
| Maximum Output Voltage Swing | ±1.0 V (into 1 MΩ load) |
Connectivity & Host Interface
| Parameter | Value |
|---|---|
| Input Connectors | 2 x BNC (Female), labeled ACTIVE (+) and REFERENCE (-) |
| Output Connector | TekProbe BNC (Male) |
| Host Oscilloscope Compatibility | Tektronix TDS, CSA, or DPO series oscilloscopes with TekProbe BNC interface; can also connect to other instruments via Tektronix 1103 Power Supply |
| Control Interface Type | Local push-button interface (on preamplifier) or remote software control via compatible host oscilloscope |
Environmental & Safety
| Parameter | Value |
|---|---|
| Storage Temperature Range | -55 °C to +75 °C |
| Operating Humidity Range | Up to 90% RH (non-condensing) |
Physical & Mechanical
| Parameter | Value |
|---|---|
| Cable Length | 1.5 m |
Environmental
| Parameter | Value |
|---|---|
| Maximum Operating Altitude | 2000 m |
| Maximum Storage Altitude | 15240 m |
Power Supply
| Parameter | Value |
|---|---|
| Power Consumption (+15 V) | 90 mA max |
| Power Consumption (+5 V) | 10 mA max |
Performance
| Parameter | Value |
|---|---|
| CMRR at DC to 10 kHz (100X Gain) | 100,000:1 (100 dB) |
| CMRR at DC to 10 kHz (10X Gain) | 10,000:1 (80 dB) |
| CMRR at DC to 10 kHz (1X Gain) | 1,000:1 (60 dB) |
| CMRR at DC to 10 kHz (0.1X Gain) | 100:1 (40 dB) |
| Noise Referred to Input (100X Gain, Full Bandwidth) | <= 30 µV RMS |
| Noise Referred to Input (100X Gain, 100 Hz LPF) | <= 3 µV RMS |
| Noise Referred to Input (10X Gain, Full Bandwidth) | <= 90 µV RMS |
| Noise Referred to Input (10X Gain, 100 Hz LPF) | <= 15 µV RMS |
| Noise Referred to Input (1X Gain, Full Bandwidth) | <= 900 µV RMS |
| Noise Referred to Input (1X Gain, 100 Hz LPF) | <= 150 µV RMS |
| Noise Referred to Input (0.1X Gain, Full Bandwidth) | <= 9.0 mV RMS |
| Noise Referred to Input (0.1X Gain, 100 Hz LPF) | <= 1.5 mV RMS |
| Input Offset Drift (100X and 10X Gain) | <= 5 µV/°C |
| Input Offset Drift (1X and 0.1X Gain) | <= 50 µV/°C |
| Gain Temperature Coefficient | <= 0.03% / °C |
| Common-Mode Overvoltage Recovery Time | < 50 µs (to recover from 40 V surge at 100X gain) |
Compliance
| Parameter | Value |
|---|---|
| Safety Standards Compliance | UL3111-1, CSA1010.1, EN61010-1 |
Technology
Active Differential Preamplifier
Applications
Low-voltage signal measurement, power supply testing, medical electronics design, and transducer signal amplification