Genuine Motorola 70V Dual Diode with Common Cathode for Radio Circuit Protection
The Motorola 4813833C02 is a high-performance 70V dual diode with common cathode configuration, designed for professional repair and maintenance of Motorola radio equipment. This genuine OEM semiconductor component provides reliable rectification, voltage protection, and signal routing in critical radio circuits. The compact SOT-23 surface-mount package with common cathode configuration offers efficient circuit design with reduced component count.
Key Features
- Genuine Motorola factory replacement part - ensures reliable performance
- Dual diode configuration with common cathode connection
- 70V voltage rating for high-voltage circuit applications
- 5B current rating for adequate power handling
- SOT-23 three-terminal surface-mount package
- Low forward voltage drop for efficient operation
- Fast switching characteristics for RF and signal applications
Compatible Models
- Various Motorola commercial and professional two-way radio models
- Used in rectification, protection, and signal routing circuits
- Consult your radio's service manual or schematic diagram for exact component location
What's Included
- One (1) Motorola 70V dual diode with common cathode
Application and Installation
Professional Installation Required: This surface-mount dual diode requires specialized soldering equipment and proper technique for installation. SMD component replacement demands precision tools including a temperature-controlled soldering station with fine tips, magnification equipment, and ESD-safe work environment. This repair should only be performed by qualified electronics technicians or certified Motorola service centers with experience in surface-mount technology.
Dual diodes with common cathode configuration are versatile components used in various radio circuits. Common applications include full-wave rectification when combined with additional components, voltage clamping and protection circuits, signal steering and switching, reverse polarity protection, and ESD protection for sensitive inputs. The 70V rating makes this component suitable for higher voltage circuits found in power supplies, transmitter stages, and protection networks.
Understanding Common Cathode Configuration: In a common cathode dual diode, two separate anode connections share a single common cathode terminal. The three-terminal SOT-23 package typically has two anodes on opposite corners and the shared cathode in the center or remaining position. This configuration is ideal for applications requiring two diodes with a shared return path, such as dual power supply rectification or dual signal protection.
Critical Installation Notes: Verify the pinout configuration before installation. The common cathode terminal must connect to the appropriate circuit node, typically ground or a common voltage rail. The two anode terminals connect to their respective signal or power inputs. Installing the component with incorrect orientation will prevent proper circuit operation and may cause damage.
Apply solder quickly to avoid overheating the diodes. Use flux to ensure good solder joints on all three SMD pads. After installation, clean any flux residue and verify proper circuit operation by measuring voltages and testing diode function with a multimeter in diode-test mode.
When to Replace
Dual diodes can fail due to overvoltage transients, excessive current, reverse voltage stress, or thermal damage. Symptoms of diode failure include no rectification, poor voltage regulation, circuit malfunction, excessive leakage current, or complete short circuit. Failed diodes may short, causing excessive current draw and potential damage to other components, or fail open, preventing proper circuit operation.
Technical Specifications
- Type: Dual Diode, Common Cathode
- Voltage Rating: 70V
- Current Rating: 5B (specific rating designation)
- Configuration: Two anodes, one common cathode
- Package: SOT-23 (3-terminal) surface-mount
- Terminals: Anode 1, Anode 2, Common Cathode
Part Numbers
- Motorola Part Number: 4813833C02
- Component Designation: 70V Dual Diode, 5B, Common Cathode
- Package Type: SOT-23 Surface-Mount
- Device Marking: 5BM (visible on component)
