Introduction
This document is the user manual for the VF-90 Voltage Follower/Linear Amplifier designed for piezoelectric (capacitive) loads, provided by Dynamic Structures and Materials, LLC. It includes safety warnings, specifications, operational instructions, and warranty information.

Safety Warnings
1. High Energy/Voltage: Caution is advised due to high energy levels at output terminals and potentially lethal voltages in the power circuit.
2. AC Source Grounding: Ensure the amplifier is connected to a grounded AC outlet.
3. Operating Precautions: Avoid flammable environments and unauthorized modifications.

Specifications
- Output Voltage: -30/+150V, -30/+200V, or ±100V
- Input Voltage Signal: Varies with output voltage configuration
- Maximum Continuous and Peak Current: 90mA
- Dimensions: Approx. 3.5” x 4” x 0.9”
- Operating Voltage: 5.5VDC input @ 3A
- Bandwidth: > 5kHz
- Electrical Noise: ~1mVrms
- Protection: Short circuit, over-current, and over-temperature

General Precautions
- Ensure insulation of leads connected to output terminals is rated at least 300V.
- Avoid using clip leads and ensure adequate airflow around the unit.
- Only drive capacitive loads; resistive or inductive loads can damage the amplifier.

Recommended Operation
The VF-90 is intended for driving low voltage piezoelectric materials and bender actuators. It applies a gain of 40 to input signals to generate suitable output voltages.

Instructions for Use
- Start-Up/Shut-Down: Connect to a load during operation to prevent damage.
- Connecting the Load: Use screw terminals for attaching piezoelectric actuators.
- Power: Use the provided AC/DC transformer for power supply.
- Input: Connect input signals through designated screw terminals.

Operation
Ensure a safe environment free of conductive objects. Follow the outlined steps for connecting the load, power, and input signals.

Circuitry Protection
The VF-90 includes protection against over-current, over-temperature, and short-circuit conditions. It will disconnect and attempt to restart if conditions are unfavorable.

Environmental Conditions
- Temperature: 0-50°C
- Humidity: 0-80% non-condensing

Cleaning
Unplug before cleaning. Use a damp cloth or compressed air, avoiding liquid contact with electrical connections.

Warranty Information
The warranty period is 60 days from shipment, covering defects in materials and workmanship. Exclusions include modifications, external damage, and improper use. Warranty claims require written notice within the warranty period.