Datasheet AD8229 (Analog Devices)

1 nV/√Hz Low Noise 210°C Instrumentation Amplifier Data Sheet AD8229 FEATURES FUNCTIONAL BLOCK DIAGRAM Designed and guaranteed for 210°C operation AD8229 Low noise –IN 1 8 +VS 1 nV/√Hz input noise RG 2 7 VOUT 45 nV/√Hz output noise RG 3 6 REF High CMRR +IN 4 5 –VS 126 dB CMRR (minimum), G = 100
01 0
TOP VIEW
2- 41
80 dB CMRR (minimum) to 5 kHz, G = 1 (Not to Scale)
09
Excellent ac specifications
Figure 1.
15 MHz bandwidth (G = 1) 100 1.2 MHz bandwidth (G = 100) 80 22 V/μs slew rate 60 THD: −130 dBc (1 kHz, G = 1) 40 Versatile 20 ±4 V to ±17 V dual supply (µV) Gain set with single resistor (G = 1 to 1000) I 0 OS Specified temperature range V –20 −40°C to +210°C, SBDIP package –40 −40°C to +175°C, SOIC package –60 APPLICATIONS –80 Down-hole instrumentation –100
6
–55 –35 –15 5 25 45 65 85 105 125 145 165 185 205 225
1 0
Harsh environment data acquisition
2-
TEMPERATURE (°C)
41 09
Exhaust gas measurements
Figure 2. Typical Input Offset vs. Temperature (G = 100)
Vibration analysis GENERAL DESCRIPTION
The AD8229 is an ultralow noise instrumentation amplifier bandwidth at high gain, for example, 1.2 MHz at G = 100. The designed for measuring small signals in the presence of large design includes circuitry to improve settling time after large common-mode voltages and high temperatures. input voltage transients. The AD8229 was designed for excellent The AD8229 has been designed for high temperature operation. distortion performance, allowing use in demanding applications The process is dielectrically isolated to avoid leakage currents at such as vibration analysis. high temperatures. The design architecture was chosen to Gain is set from 1 to 1000 with a single resistor. A reference pin compensate for the low VBE voltages at high temperatures. allows the user to offset the output voltage. This feature can be The AD8229 excels at measuring tiny signals. It delivers industry useful when interfacing with analog-to-digital converters. leading 1 nV/√Hz input noise performance. The high CMRR of For the most demanding applications, the AD8229 is available the AD8229 prevents unwanted signals from corrupting the in an 8-lead side-brazed ceramic dual in-line package (SBDIP). acquisition. The CMRR increases as the gain increases, offering For space-constrained applications, the AD8229 is available in high rejection when it is most needed. an 8-lead plastic standard small outline package (SOIC). The AD8229 is one of the fastest instrumentation amplifiers available. Its current feedback architecture provides high
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Document Outline Features Applications Functional Block Diagram General Description Revision History Specifications Absolute Maximum Ratings Predicted Lifetime vs. Operating Temperature Thermal Resistance ESD Caution Pin Configuration and Function Descriptions Typical Performance Characteristics Theory of Operation Architecture Gain Selection RG Power Dissipation Reference Terminal Input Voltage Range Layout Common-Mode Rejection Ratio over Frequency Power Supplies Reference Pin Input Bias Current Return Path Input Protection Input Voltages Beyond the Rails Large Differential Input Voltage at High Gain IMAX Radio Frequency Interference (RFI) Calculating the Noise of the Input Stage Source Resistance Noise Voltage Noise of the Instrumentation Amplifier Current Noise of the Instrumentation Amplifier Total Noise Density Calculation Outline Dimensions Ordering Guide