Overview
The AD640BP is a complete monolithic logarithmic amplifier produced by Analog Devices Inc. This device is designed to provide high precision and stability over a wide range of supply voltages and temperatures. It is particularly useful in applications requiring logarithmic signal processing from DC to 120 MHz.
Key Specifications
| Parameter | Conditions | Min | Typ | Max |
|---|---|---|---|---|
| SIGNAL INPUTS (Pins 1, 20) | Input Capacitance Either Pin to COM | 2 pF | 2 pF | 2 pF |
| Noise Spectral Density | 1 kHz to 10 MHz | 2 nV/√Hz | 2 nV/√Hz | 2 nV/√Hz |
| Tangential Sensitivity BW = 100 MHz | -72 dBm | -72 dBm | -72 dBm | |
| 3 dB BANDWIDTH Each Stage | 350 MHz | 350 MHz | 350 MHz | |
| LOGARITHMIC OUTPUTS Slope Current, IY f < 1 MHz | 0.96 mA | 1.0 mA | 1.04 mA | |
| Supply Voltage Range | ±4.5 V | ±7.5 V | ||
| Temperature Range (AD640BP) | -40°C | +85°C |
Key Features
- Complete, fully calibrated monolithic system with five stages, each having 10 dB gain and 350 MHz bandwidth.
- Direct coupled fully differential signal path.
- Logarithmic slope, intercept, and AC response stable over full military temperature range.
- Dual polarity current outputs scaled at 1 mA/decade.
- Low power operation (typically 220 mW at ±5 V).
- Available in 20-lead side-brazed ceramic DIPs or leadless chip carriers (LCC), and 20-lead plastic DIP (N) and PLCC (P) packages.
Applications
- Radar, sonar, ultrasonic, and audio systems.
- Precision instrumentation from DC to 120 MHz.
- Power measurement with absolute calibration.
- Wide range high accuracy signal compression.
- Alternative to discrete and hybrid IF strips.
- Replaces several discrete log amp ICs.
Q & A
- What is the AD640BP used for? The AD640BP is used for logarithmic signal processing in various applications including radar, sonar, ultrasonic, and audio systems.
- What is the dynamic range of the AD640BP? A single AD640BP provides up to 50 dB of dynamic range for frequencies from DC to 120 MHz.
- How many stages does the AD640BP have? The AD640BP has five cascaded dc-coupled amplifier/limiter stages.
- What is the bandwidth of each stage? Each stage has a –3 dB bandwidth of 350 MHz.
- What are the temperature ranges for the AD640BP? The AD640BP is specified for the industrial temperature range of –40°C to +85°C.
- What are the package options for the AD640BP? The AD640BP is available in 20-lead side-brazed ceramic DIPs, leadless chip carriers (LCC), 20-lead plastic DIP (N), and PLCC (P) packages.
- How does the AD640BP handle logarithmic output? The AD640BP provides logarithmic output with a slope current scaled at 1 mA per decade.
- Can the AD640BP be used in cascade? Yes, two AD640BPs in cascade can provide up to 95 dB of dynamic range at reduced bandwidth.
- What is the power consumption of the AD640BP? The AD640BP operates with low power consumption, typically 220 mW at ±5 V.
- Is the AD640BP calibrated? Yes, the AD640BP is laser calibrated to close tolerances and maintains high accuracy over the full military temperature range.
