Overview
The AD603ARZ-REEL, produced by Analog Devices Inc., is a low noise, voltage-controlled amplifier designed for use in RF and IF AGC (Automatic Gain Control) systems. This amplifier is part of the X-AMP® family, which features a patented proprietary circuit topology combining a variable attenuator with a fixed-gain amplifier. This design ensures accurate, pin-selectable gains and low noise performance. The AD603 is available in an 8-Lead SOIC package and is specified for operation from −40°C to +85°C.
Key Specifications
| Parameter | Conditions | Min | Typ | Max | Unit |
|---|---|---|---|---|---|
| Input Resistance | Pin 3 to Pin 4 | 97 | 100 | 103 | Ω |
| Input Capacitance | 2 | pF | |||
| Input Noise Spectral Density | Input short-circuited | 1.3 | nV/√Hz | ||
| Noise Figure | f = 10 MHz, gain = maximum, RS = 10 Ω | 8.8 | dB | ||
| 1 dB Compression Point | f = 10 MHz, gain = maximum, RS = 10 Ω | −11 | dBm | ||
| Peak Input Voltage | ±1.4 | ±2 | V | ||
| −3 dB Bandwidth | VOUT = 100 mV rms | 90 | MHz | ||
| Power Consumption | VS = ±5 V | 125 | mW | ||
| Gain Range | −11 dB to +31 dB (90 MHz bandwidth) | dB | |||
| Gain Control Response Time | For a 40 dB change | < 1 | μs |
Key Features
- Low Noise Performance: Input noise spectral density of 1.3 nV/√Hz, making it suitable for high-sensitivity applications.
- Variable Gain Control: Accurate, pin-selectable gains from −11 dB to +31 dB with a bandwidth of 90 MHz, or +9 dB to +51 dB with a bandwidth of 9 MHz. Intermediate gain ranges can be set using an external resistor.
- High Impedance Gain Control Interface: Differential input with high impedance (50 MΩ) and low bias (200 nA), allowing for either differential or single-ended control voltages.
- Fast Gain Control Response: Less than 1 μs response time for a 40 dB gain change.
- Low Distortion Output: Can drive load impedances as low as 100 Ω with low distortion. Total harmonic distortion of −60 dBc for a ±1 V sinusoidal output at 10 MHz into a 500 Ω load.
- Wide Operating Temperature Range: Specified for operation from −40°C to +85°C.
Applications
- RF/IF AGC Amplifiers: Ideal for automatic gain control in RF and IF systems due to its accurate and stable gain control.
- Video Gain Controls: Suitable for video applications requiring precise gain adjustment.
- A/D Range Extensions: Can be used to extend the dynamic range of analog-to-digital converters.
- Signal Measurements: Useful in various signal measurement applications requiring low noise and variable gain.
Q & A
- What is the input noise spectral density of the AD603?
The input noise spectral density of the AD603 is 1.3 nV/√Hz.
- What is the gain range of the AD603?
The AD603 provides gains from −11 dB to +31 dB with a bandwidth of 90 MHz, or +9 dB to +51 dB with a bandwidth of 9 MHz.
- How is the gain controlled in the AD603?
The gain is controlled through a high impedance (50 MΩ), low bias (200 nA) differential input, with a scaling of 25 mV/dB.
- What is the response time for a 40 dB gain change in the AD603?
The response time for a 40 dB gain change is less than 1 μs.
- What is the minimum load impedance the AD603 can drive?
The AD603 can drive a load impedance as low as 100 Ω with low distortion.
- What is the total harmonic distortion for a ±1 V sinusoidal output at 10 MHz into a 500 Ω load?
The total harmonic distortion is typically −60 dBc for a ±1 V sinusoidal output at 10 MHz into a 500 Ω load.
- What is the peak specified output voltage of the AD603?
The peak specified output voltage is ±2.5 V minimum into a 500 Ω load.
- Can multiple AD603 amplifiers be cascaded?
Yes, multiple AD603 amplifiers can be cascaded and their gain control gains offset to optimize the system SNR.
- What is the operating temperature range of the AD603?
The AD603 is specified for operation from −40°C to +85°C.
- What package types are available for the AD603?
The AD603 is available in an 8-Lead SOIC package among others.
