10D 471K Metal Voltage Dependent Resistor

10D471K Metal Oxide Varistor (MOV) is a critical surge protection component designed to safeguard sensitive electronic circuits from damaging voltage transients caused by lightning, switching, or electrical noise. This specific model, the 10D471K, is a metal oxide varistor (MOV) with a disc diameter of 10 mm and a nominal varistor voltage of 470 V. Consequently, it acts as a voltage-dependent, non-linear resistor, offering an extremely high impedance under normal operating conditions. However, when the transient voltage exceeds the clamping voltage, the MOV immediately transitions to a highly conductive state, diverting the excessive energy away from the protected components. Therefore, incorporating the 10D471K into your power supplies and line protection circuits provides reliable, fast-acting, and cost-effective protection against unexpected voltage spikes.

Key Features:

• High Surge Current Capability: The 10D series offers substantial maximum surge current capacity, effectively absorbing and dissipating large transient energy pulses.
• Fast Response Time: This MOV provides an extremely fast response time, typically less than 25 ns, ensuring immediate protection when a voltage spike occurs.
• Wide Operating Temperature: The component maintains its protection characteristics across a broad temperature range, making it suitable for diverse operational environments.
• Radial Leaded Package: The epoxy-coated, radial-leaded configuration simplifies through-hole mounting onto standard printed circuit boards (PCBs).
• Energy Absorption: Designed to reliably absorb and dissipate transient energy, protecting downstream components from damage.

Technical Specifications:

• Nominal Varistor Voltage (V_N): 470 V (±10% tolerance)
• Maximum Allowable AC Voltage (V_AC): 300 V_rms
• Maximum Allowable DC Voltage (V_DC): 385 V
• Maximum Clamping Voltage (V_C): 775 V (at I_P = 5 A)
• Maximum Peak Current (I_PM): 2500 A (8/20 $\mu$s pulse)
• Nominal Disc Diameter: 10 mm
• Capacitance (C): ≈ 250 pF (at 1 kHz)
• Energy Rating (W_TM): 65 J (Joule rating for 10/1000 $\mu$s pulse)

Mechanical Specifications:

• Component Material: Metal Oxide (Zinc Oxide)
• Package Style: Radial Disc, Through-Hole
• Coating: Flame-retardant epoxy resin (UL 94 V-0 recognized)
• Lead Material: Tinned Copper
• Operating Temperature Range: −40°C to +85°C

Dimensions:

• Disc Diameter (D): ≈ 11.5 mm
• Body Thickness (T): ≈ 4.0 mm
• Lead Pitch (P): 7.5 ± 1.0 mm (Standard for 10D series)
• Lead Diameter: ≈ 0.8 mm

Pinout and Wiring:

• Two-Terminal Component: The MOV is a non-polar component, meaning you can connect it in either direction across the voltage lines.
• Connection Strategy: Connect the MOV in parallel with the circuit or component you want to protect.
• Standard Placement: Place the MOV between Line-Neutral, Line-Ground, or Neutral-Ground in AC systems, or across the DC rails in DC circuits.
• Series Protection Note: Always install the MOV after a fuse or circuit breaker. This ensures the protection device will clear the fault if the MOV fails due to an extreme surge.

Datasheet Reference:

• Download Littelfuse 10D Varistor Series Datasheet

Commonly Used in:

• AC Power Supplies: Essential component in primary and secondary side surge suppression for power bricks and linear supplies.
• Consumer Electronics: Protecting TVs, audio equipment, gaming consoles, and computers from external transients.
• Industrial Control Systems: Used in PLCs, motor drives, and sensor interfaces to shield control circuitry from electrical noise on long wire runs.

Applications:

• Line Voltage Suppression: Clamping voltage transients that enter via the main AC input line.
• Switching Circuit Protection: Mitigating surges generated by switching inductive loads like relays and solenoids.
• Semiconductor Protection: Protecting sensitive semiconductors (like diodes, transistors, and ICs) from overvoltage conditions.
• Power Distribution Boards: Serving as the first line of defense against high-energy surges on the circuit board level.

Equivalent Models:

• Varistor 10D471: The base part number without the ‘K’ tolerance code (functionally identical).
• B72210S0271K101 (EPCOS/TDK): A directly comparable 10 mm radial lead MOV with a 470V nominal voltage.
• V10K300 (Vishay): An alternative 10 mm MOV commonly used in 230 V_AC line protection applications.
• 7D 471K: Same voltage rating but a smaller 7mm diameter disc.
• 14D 471K: Larger 14mm diameter disc, typically offering higher surge current capacity.
• TVS Diode: A different technology offering faster response times and a lower clamping voltage, but with lower surge energy handling.

Package Includes:

• 1 x 10D 471K Metal Voltage Dependent Resistor