MCP2003AT-E/SN LIN Bus Transceiver: Datasheet, Application Circuit, and Pinout Configuration
The MCP2003AT-E/SN is a local interconnect network (LIN) transceiver from Microchip Technology, serving as a physical layer interface between a LIN protocol controller and the LIN bus. This device is compliant with the LIN 2.0, LIN 2.1, LIN 2.2, and SAE J2602 standards, making it a versatile and reliable solution for automotive and industrial networking applications. It is designed to operate from a wide supply voltage range of 5.5V to 27V, providing robustness against the harsh electrical environments typical in vehicles.
A primary feature of the MCP2003AT-E/SN is its integrated voltage regulator that provides a stable 5V/50mA output, which can be used to power an external microcontroller or LIN protocol controller, simplifying system design and reducing component count. The transceiver supports data rates up to 20 kbps and features excellent electromagnetic compatibility (EMC) and electrostatic discharge (ESD) protection, safeguarding the network from transient disturbances.
Pinout Configuration
The MCP2003AT-E/SN is available in an 8-pin SOIC (SN) package. Its pin configuration is as follows:
Pin 1 (TXD): Transmit Data Input. This pin is connected to the UART TX line of the host microcontroller.
Pin 2 (RXD): Receive Data Output. This pin is connected to the UART RX line of the host microcontroller.
Pin 3 (EN): Enable Input. A high-level input enables the device; a low-level input places it in a low-power sleep mode.
Pin 4 (Vsup): Battery Supply Voltage Input. This is the main power input connected directly to the vehicle battery.
Pin 5 (LIN): LIN Bus Input/Output. This pin connects to the LIN bus line via a series resistor and a pull-up resistor to the battery.
Pin 6 (WAKE): Wake-up Input/Open-drain Output. This pin can be used to wake the device from sleep mode via the LIN bus.
Pin 7 (Vreg): 5V Regulator Output. This pin provides a 5V supply for an external microcontroller.
Pin 8 (GND): Ground.
Application Circuit
A typical application circuit for the MCP2003AT-E/SN is straightforward. The Vsup pin is connected to the vehicle battery (12V or 24V) through a series diode for reverse battery protection. A 1 kΩ resistor is placed in series between the LIN pin and the actual bus line to limit current. The LIN bus itself requires a pull-up resistor (typically 1 kΩ) to Vsup and a series diode to ensure proper operation. The host microcontroller is powered from the Vreg pin, while its UART pins are directly connected to TXD and RXD. The EN pin can be controlled by the microcontroller for managing power modes.
Datasheet Key Parameters
Key parameters outlined in the datasheet include:
Sleep Mode Current: Very low current consumption (typ. 10 µA) when disabled, crucial for battery-life preservation.
ESD Protection: High ESD protection of ±8 kV (on LIN pin) per IEC 61000-4-2.
Thermal Shutdown: Integrated protection feature that disables the output driver in case of excessive junction temperature.
Current Limiting: Built-in protection on the LIN pin against short circuits to ground and battery.
The MCP2003AT-E/SN is a highly integrated and robust solution for implementing LIN network nodes. Its compliance with major LIN standards, integrated voltage regulator, and superior protection features make it an ideal choice for cost-sensitive automotive applications like sensors, actuators, and smart switches. Its simplicity and reliability ensure stable communication within the challenging environment of an automobile.
Keywords: LIN Bus Transceiver, Automotive Networking, MCP2003AT-E/SN, Physical Layer Interface, ESD Protection.
