Part A
AD8306AR
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 7304 Stückzahl
- Package
- SOIC-16
- Series
- Linear-Verstärker
Replacement verdict
Not a drop-in replacement
The AD8307ARZ and AD8306AR are both logarithmic amplifiers, but they are not functionally interchangeable: the AD8306AR integrates a limiting amplifier with RSSI output and differential signal path, while the AD8307ARZ provides a single-ended logarithmic detector output, and their bandwidth, dynamic range, and package/pinout differ. Direct substitution is not recommended without circuit redesign and validation.
Different output type
Different bandwidth
Different dynamic range
Different pinout
Parts at a glance
Part B
AD8307ARZ
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 6156 Stückzahl
- Package
- SOIC-8
- Series
- Linear-Verstärker
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | AD8307ARZ | AD8306AR | Why it matters |
|---|---|---|---|
| Function | Logarithmic amplifier / RSSI detector | Limiting amplifier with RSSI | Defines the core signal-processing role; a log amp and a limiting amplifier are not directly interchangeable in most circuits. |
| Frequency Range | DC to 500 MHz | 5 MHz to 400 MHz | Operating bandwidth must cover the application's signal spectrum for valid detection. |
| Dynamic Range | 92 dB | 100 dB | Determines the span of input signal levels the device can measure accurately. |
| Logarithmic Slope | 25 mV/dB | 20 mV/dB | Slope sets the output voltage change per dB of input, affecting scaling and calibration of the measurement. |
| Logarithmic Intercept | -84 dBm | -95 dBm | Intercept defines the reference point of the log transfer function and must match the system's calibration. |
| Supply Voltage | 2.7 V to 5.5 V | 2.7 V to 6.5 V | Supply range must be compatible with the system's power rail for proper operation. |
| Supply Current | 7.5 mA typical | 16 mA typical | Affects power budget and thermal considerations in the design. |
| Package | 8-Lead SOIC | 16-Lead SOIC | Footprint and pin count differ, so board layout and pinout compatibility are not interchangeable. |
| Output Type | Voltage output (RSSI) | Voltage output (RSSI) plus limiter outputs | The AD8306 provides additional limiting amplifier outputs, enabling different downstream signal-chain architectures. |
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Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | AD8306AR | AD8307ARZ |
|---|---|---|
| Part Status | Obsolete | Active |
| Type | Limiting-Logarithmic Amplifier | Logarithmic Amplifier |
| Applications | Receiver Signal Strength Indication (RSSI) | Receiver Signal Strength Indication (RSSI) |
| Mounting Type | Surface Mount | Surface Mount |
Frequently asked questions
What are the primary functional differences between the AD8307ARZ and the AD8306AR?
The AD8307ARZ is a DC-to-500 MHz, 92 dB logarithmic amplifier (log amp) that provides a linear-in-dB output proportional to the log of the input signal's absolute value. The AD8306AR is a 5 MHz-to-400 MHz, 100 dB limiting logarithmic amplifier that provides both a logarithmic (RSSI) output and a limited output signal. The AD8307ARZ is optimized for signal strength measurement, while the AD8306AR is designed for received signal strength indication (RSSI) and amplitude-shift keying (ASK) demodulation in RF/IF systems.
Are the AD8307ARZ and AD8306AR pin-compatible and package-compatible?
No. The AD8307ARZ is supplied in an 8-lead SOIC package (SOIC-8), while the AD8306AR is supplied in a 16-lead SOIC package (SOIC-16). The pin counts, pin functions, and PCB land patterns differ, so these devices are not drop-in replacements for one another.
What are the specified operating frequency ranges for each device?
The AD8307ARZ operates from DC to 500 MHz. The AD8306AR operates from 5 MHz to 400 MHz. Designs requiring operation below 5 MHz or above 400 MHz should not use the AD8306AR within its specified range.
How do the logarithmic dynamic ranges of the AD8307ARZ and AD8306AR compare?
The AD8307ARZ provides a nominal 92 dB dynamic range with a logarithmic slope of 25 mV/dB. The AD8306AR provides a nominal 100 dB dynamic range with a logarithmic slope of 20 mV/dB. The AD8306AR therefore offers a wider logarithmic range, while the AD8307ARZ offers a higher slope for greater output voltage change per dB.
Does the AD8306AR provide a limited output that the AD8307ARZ does not?
Yes. The AD8306AR includes a limiting amplifier output that provides a constant-amplitude output signal for input levels above its limiting threshold, in addition to its logarithmic RSSI output. The AD8307ARZ provides only a logarithmic output and does not include a limiting output stage.
What are the supply voltage and current consumption specifications for these devices?
Both devices operate from a single supply. The AD8307ARZ operates from a 2.7 V to 5.5 V supply and typically draws about 7.5 mA. The AD8306AR operates from a 2.7 V to 5.5 V supply and typically draws about 16 mA. The AD8306AR's higher current consumption reflects its additional limiting amplifier circuitry.
Can the AD8307ARZ and AD8306AR be used interchangeably in an existing design?
No. Because the devices differ in package, pinout, frequency range, dynamic range, logarithmic slope, and output functionality, they are not interchangeable without redesigning the PCB and revalidating the circuit against the target device's datasheet specifications.