SLOSEB2 February   2026 VCA710

ADVANCE INFORMATION  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Thermal Information
    4. 5.4 Recommended Operating Conditions
    5. 5.5 Electrical Characteristics for LNA
    6. 5.6 Electrical Characteristics for VGA
    7. 5.7 Typical Characteristics: Low-Noise Amplifier (LNA)
    8. 5.8 Typical Characteristics: Variable Gain Amplifier (VGA)
    9. 5.9 Typical Characteristics: Low-Noise Amplifier + Variable Gain Amplifier
  7. 6 Parameter Measurement Information
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Device Functional Modes
  9. 8 Application and Implementation
    1. 8.1 Typical Application
      1. 8.1.1 Ultrasound Flow Meter Front-End
      2. 8.1.2 Design Requirements
      3. 8.1.3 Detailed Design Procedure
      4. 8.1.4 Optical Receiver Front-end
    2. 8.2 Power Supply Recommendations
    3. 8.3 Layout
      1. 8.3.1 Layout Guidelines
      2. 8.3.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Device Support
    2. 9.2 Receiving Notification of Documentation Updates
    3. 9.3 Support Resources
    4. 9.4 Trademarks
    5. 9.5 Electrostatic Discharge Caution
    6. 9.6 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information
    1. 11.1 Tape and Reel Information
    2. 11.2 Mechanical Data

7.3 Device Functional Modes

The VCA710 operates in several functional modes determined primarily by the control pins and the amplifiers supply conditions. These modes define how the device shapes, scales, and conditions signals across AC and DC applications.

Normal Operation Mode

In this mode, the device functions as a single-channel, low-noise variable-gain amplifier (VGA). Both the low-noise amplifier (LNA) and VGA paths operate from a 3.3V to 5.25V supply, providing low noise and high dynamic range. This is the default mode whenever the device is powered and all pins are within valid operating ranges and all the sub-blocks are enabled.

  • LNA + VGA enabled
    • In this mode EN_ VGA is high and EN_ LNA is high, LNA is AC coupled and VGA is either AC or DC coupled.
  • LNA only enabled
    • In this mode EN_LNA is high, EN_VGA is low. Only LNA is in enabled state and VGA is disabled. The LNA block is used independently as a 0.9nV/√Hz input referred 20dB gain block.
  • VGA only enabled
    • In this mode EN_VGA is high, EN_LNA is low. Only VGA is in enabled state and LNA is disabled. For applications where internal LNA of the VCA710 cannot be used TI recommends using this mode.

Gain Modes

The VCA710 supports two selectable gain-scaling behaviors, controlled by the HILO pin. This pin selects an internal 40dB/20dB fixed gain amplifier (FGA).

  • High Gain mode / FGA = 40dB (HILO = 1)
    • Gain range: –12 dB to +40dB
    • Optimized for higher overall gain, better distortions, better input and output noise at higher gains.
    • Suitable for broadband front ends and low-level inputs that require wide scaling.
  • Low Gain mode / FGA = 20dB (HILO = 0)
    • Gain range: –32 dB to +20dB
    • Optimized for applications requiring lower noise at lower gain and better voltage offset.
    • Suitable for higher ENOB ADC.

Besides the above two gains from the FGA the GAIN_ADJ pin accepts an analog control voltage that smoothly adjusts attenuation from 0dB to -52dB via an interpolator. Overall VGA gain = interpolator gain + FGA gain.

Input common mode selection for VGA

  • Input common mode generated internally, VICM enable
    • In this mode EN_VICM = 1, input common mode is set to mid supply internally and inputs are expected to be AC coupled.
  • Input common mode set externally, VICM disable
    • In this mode EN_VICM = 0, input common mode is set externally via applied input signal. This mode allows DC coupling of input signals. The common mode = (VIP_VGA + VIM_VGA) / 2. Make sure the input common mode is within the specified range specified as per the electrical characteristics.