IC-Mart Your Trusted Source for Logarithmic Amplifiers IC Chips

(from leading manufacturers)

Global Logarithmic Amplifiers IC Manufacturers and Product Categories

1. Analog Devices (ADI) — Industry Leader

ADI offers the most comprehensive Log Amp portfolio. Their range covers everything from micro-DC current detection to RF detection above 10GHz.

• Precision Log Converters (Transimpedance/DC):
  • Models: AD8304, AD8305, ADL5303, ADL5304, ADL5310 (Dual-channel).
  • Applications: Fiber optic power monitoring, medical chemical analysis, micro-current measurement.
• RF Demodulating Log Amps (RF/RSSI):
  • Models: AD8307 (Classic), AD8309, AD8310, AD8313, AD8317, AD8318 (Up to 8GHz), AD8319.
  • Applications: RSSI (Received Signal Strength Indication), transmit power control.
• Power Detectors (TruPwr™ / RMS Response):
  • Models: AD8361, AD8362, AD8364, ADL5519 (10GHz Dual-channel).
  • Applications: Precise measurement of non-regular waveforms.
• Successive Detection Log Video Amps (SDLVA):
  • Models: AD640, AD641, AD606 (Legacy).
  • Applications: Radar pulse processing, ultrasonic detection.

2. Texas Instruments (TI) — Precision Experts

Most TI Log Amps inherited the Burr-Brown technical legacy. They dominate the market in precision DC measurement and log-ratio calculations.

• Precision & Log Ratio Amplifiers:
  • Models: LOG101, LOG102, LOG104, LOG112, LOG114 (High-speed single-supply), LOG2112 (High-precision dual-channel).
  • Applications: Spectrophotometers, absorbance measurement, analog computation.
• High-Speed Log Detectors:
  • Models: LOG200, LOG300 (Latest 50MHz bandwidth models).
  • Applications: High-speed laser communication control, Optical Network Units (ONU).
• General Purpose / RF Log Amps:
  • Models: TL441 (Classic multi-stage cascaded model for legacy instruments).

3. Maxim Integrated (Now part of ADI)

Maxim focuses on low-power and compact designs, particularly for Power Amplifier (PA) controllers.

• Precision Transimpedance Type:
  • Models: MAX4206, MAX4207.
  • Features: Ultra-low input bias current; optimized for photodetectors.
• RF PA Controllers:
  • Models: MAX4000, MAX4001, MAX4002.
  • Applications: RSSI for mobile phones and wireless terminals.

4. Hittite Microwave (Now part of ADI)

Hittite is known for high-performance microwave components. Their Log Amps target military, aerospace, and high-end communication sectors.

• Ultra-High Frequency SDLVA:
  • Models: HMC601, HMC602, HMC613, HMC948 (1-18GHz).
  • Features: Extremely wide frequency range and nanosecond-level pulse rise times.

Global Manufacturer Comparison Table

Manufacturer	Core Series	Key Strengths	Recommended Models
ADI	AD83xx, ADL5xxx	RF, Wide Dynamic Range, RMS Detection	AD8307, ADL5304
TI	LOGxxx	Precision Log Ratio, Low Power DC	LOG114, LOG2112
Maxim	MAX420x, MAX400x	Compact PA Control, Precision Conversion	MAX4206, MAX4002
Hittite	HMCxxx	10GHz+ Ultra-High Frequency, Radar	HMC948, HMC613

Chinese Manufacturers and Domestic Equivalents

1. 3PEAK

A leader in Chinese analog chips. Known for high performance and stability in industrial and communication sectors.

• Models: TPM8307 (Equiv. to AD8307), TPM8310 (Equiv. to AD8310).
• Features: Targets RF power detection; pin-to-pin compatible with global standards.

2. Sitrium (Analogue)

Strong expertise in industrial interface and linear analog chips. Offers high cost-performance ratios.

• Models: SIT8307 (AD8307 compatible), SIT8310 (AD8310 compatible).
• Features: Wide dynamic range for RSSI, power measurement, and medical instruments.

3. Gainsil

Focuses on high-performance analog and mixed-signal chips for general markets.

• Models: GS8307 (AD8307 equivalent), GS8310 (AD8310 equivalent).
• Features: Highly competitive pricing for wireless modules and consumer electronics.

4. HXY

Focused on high-performance analog power and precision amplifiers for industrial and military use.

• Models: HXY8307 (AD8307 equivalent), HXY8310 (AD8310 equivalent).
• Features: High environmental adaptability and excellent temperature drift performance.

5. CBM

Specializes in RF front-end ICs. Offers integrated and standalone power detectors.

• Models: High-frequency RF detection series (up to 6GHz+) for 5G and Wi-Fi 6.

Domestic Replacement Comparison Table

International Model	Chinese Manufacturer	Domestic Equivalent	Applications
AD8307 (500MHz)	3PEAK / Sitrium / Gainsil	TPM8307 / SIT8307 / GS8307	RF Power, Low-cost RSSI
AD8310 (440MHz)	3PEAK / Sitrium	TPM8310 / SIT8310	High-speed RSSI, Video Log
LOG114 (Precision)	Specialty Labs (e.g., 771)	Customized Models	Medical, Optical Detection
AD8318 (8GHz)	CBM / RF Specialists	High-performance Detectors	Base Station, Radar

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Why Use Logarithmic Amplifiers?

Electronic signals often have extreme dynamic ranges. For example, a sensor’s current might vary from 1nA to 1mA—a million-fold difference (120dB).

• Linear Amp Limitations: If the gain is high for small signals, large signals will saturate. If the gain is low for large signals, small signals are lost in noise.
• The Log Amp Advantage: They provide Dynamic Range Compression. By compressing a wide input range into a narrow output range (e.g., 0V to 5V), they maintain consistent measurement precision in decibels across the entire range.

Typical Application Scenarios

1. RF Power Measurement & Control: RSSI for base stations/routers and transmit power compensation for RF transmitters.
2. Fiber Optics: Optical power monitoring and laser drive control.
3. Medical & Analytical Instruments: Spectrophotometers (based on the Beer-Lambert Law) and ultrasound/radar image processing.
4. Industrial Automation: Sensor linearization and vibration monitoring for heavy machinery.

Classifications of Logarithmic Amplifiers

1. DC / Low-Frequency Precision Log Amps

Based on the PN junction characteristics of transistors (Vbe vs. Ic). Designed for DC current or low-frequency signals.

• Logic: Output voltage is proportional to the log of the input current.
• Models: TI (LOG114, LOG2112, LOG101); ADI (ADL5303, ADL5304, AD8304); Maxim (MAX4206).

2. RF / Demodulating Log Amps

Uses a “Successive Detection” architecture with cascaded gain stages. They demodulate high-frequency RF signals into a DC voltage representing envelope power.

• Logic: Input is RF/AC; output is RSSI. Voltage is linear to input power (dBm).
• Models: ADI (AD8307, AD8310, AD8318); TI (LOG300, TL441).

3. Logarithmic Ratio Amplifiers

Integrates two log units and a subtraction circuit to calculate the ratio of two signals.

• Logic: Vout​∝log(I1​/I2​). Naturally cancels fluctuations in light sources or temperature.
• Models: TI (LOG101, LOG102); ADI (ADL5304).

4. Successive Detection Log Video Amps (SDLVA)

A specialized demodulating amp with nanosecond response times. It preserves the envelope of fast pulses.

• Logic: High rise times and video bandwidth for radar and electronic warfare.
• Models: ADI (AD640, AD641); Hittite (HMC613, HMC948).

Classification Summary Table

Category	Core Logic	Main Applications	Top Manufacturers	Recommended Models
Precision (DC)	V∝log(Iin​)	Medical, Optical Power	TI, ADI, Maxim	LOG114, ADL5303
Demodulating (RF)	V∝Power (dBm)	RSSI, Base Stations	ADI, TI	AD8307, AD8318
Log Ratio	V∝log(A/B)	Absorbance / Reflectance	TI	LOG101, LOG104
Video (SDLVA)	Ultra-fast Pulse Resp.	Radar, Pulse Processing	ADI (Hittite)	AD640, HMC948