DC Block
Designed to prevent the flow of direct current (DC) while allowing RF signals to pass through, DC blocks are essential passive components in protecting sensitive equipment and maintaining signal integrity across RF systems. They are commonly used to isolate DC voltages, protect measurement instruments, and eliminate unwanted current paths.
- Broadband – Covers 380 MHz to 2700 MHz
- Low Insertion Loss
- Low PIM Device, -160 dBc
- iBwave Supported
ClearComm DC Blocks by MCV
ClearComm DC blocks by MCV are engineered for reliable broadband performance, low insertion loss, and excellent return loss across a wide frequency range. Available in inner, outer, and inner/outer configurations, our DC blocks are built with precision to support demanding applications such as wireless infrastructure, test and measurement setups, aerospace systems, and satellite communications. Housed in rugged connectorized designs, our DC blocks provide consistent, dependable isolation and performance in environments where clean signal flow is essential.
DC Block models and configuration types
FAQ about DC block
What is a DC block?
A DC block is a passive RF component that allows RF signals to pass through while blocking DC (direct current) and very low-frequency signals. It’s commonly used to isolate DC voltages between different parts of a system.
How does a DC block work?
A DC block works by using a capacitor in series with the signal path. Since capacitors block DC and pass AC, the DC block stops any DC voltage or offset from passing through, while allowing RF signals to flow with minimal loss.
What are the types of DC blocks?
There are three main types:
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Inner-only DC block: Blocks DC on the center conductor only
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Outer-only DC block: Blocks DC on the outer shield or ground
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Inner/outer (series) DC block: Blocks DC on both the center conductor and outer shield
Each type is chosen based on grounding schemes and system requirements.
What are typical applications of DC blocks?
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Protecting sensitive equipment from unwanted DC voltages
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Preventing ground loops in test setups
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Isolating bias voltages in RF systems
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Signal injection or extraction without affecting DC bias
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Antenna testing and calibration
What frequency ranges do DC blocks support?
High-quality DC blocks can operate from kHz up to tens of GHz, depending on their design. Always check the specified operating frequency range to ensure minimal insertion loss at your desired frequency.
What are key specifications for a DC block?
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Frequency range
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Voltage rating (maximum DC voltage blocked)
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Insertion loss (ideally very low, typically < 0.2 dB)
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Return loss / VSWR
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Impedance (usually 50 ohms)
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Connector type (SMA, N-type, 2.92mm, etc.)
Can DC blocks affect RF performance?
Yes, if not properly selected. Poor-quality or mismatched DC blocks can introduce:
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Insertion loss
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Signal reflection (high VSWR)
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Impedance mismatch
It’s important to use DC blocks that match your frequency, power, and impedance requirements.
What's the difference between a DC block and a bias tee?
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A DC block allows RF to pass but blocks DC.
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A bias tee allows RF and DC to coexist, injecting or extracting DC while passing RF.
Both use capacitors and inductors but serve opposite purposes.
Can I use a DC block with a high-power RF signal?
It depends on the power handling of the DC block. Most are rated for low to moderate RF power (e.g., up to a few watts). For high-power applications, use DC blocks specifically rated for higher power levels to avoid damage or failure.
How do I choose the right DC block for my application?
Consider the following:
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Frequency range of your RF signal
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Connector type and gender
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DC voltage you need to block
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Power handling requirements
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Type (inner, outer, or both) based on your grounding needs
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Form factor if space is limited
How can I order DC block from MCV Microwave?
To place an order for DC block or any other RF products please contact us and we will help you!