The TD1040 is a high-speed CAN (Controller Area Network) transceiver fully compliant with the ISO 11898-2 standard, designed for automotive electronics, industrial control, trucks, buses, and embedded systems. Acting as the physical interface between a CAN protocol controller and the differential bus, it supports data rates up to 1 Mbps, features excellent EMI immunity, comprehensive protection mechanisms, and a low-power standby mode—making it a key component for robust CAN networks.
1. Key Features (from TD1040.PDF)
Supply Voltage (VCC): 4.5 V to 5.5 V
Max Data Rate: 1 Mbps (NRZ encoding)
Differential Output Voltage (Dominant): 1.5 V to 3.0 V
Node Capacity: Supports at least 110 nodes on one bus
Operating Temperature: –40°C to +125°C (automotive/industrial grade)
Package: SOP-8 or DIP-8 (green, lead-free)
Pin Functions:
TXD: Transmit data input (from MCU)
RXD: Receive data output (to MCU)
STB: Standby mode control (Low = High-Speed, High = Standby)
SPLIT: Common-mode stabilization output (for EMC)
CANH / CANL: Differential bus interface
2. Key Usage Guidelines
(1) Operating Mode Control (STB Pin)
High-Speed Mode: STB = Low (0V) or floating → Full transceiver active, supports 1 Mbps.
Standby Mode: STB = High (VCC) → Transmitter disabled; only a low-power comparator monitors the bus. Quiescent current is typically 5 μA.
Bus Wake-Up: In standby, a dominant bus state lasting ≥ tBUS (0.7–5 μs) forces RXD low, signaling the MCU to wake up and pull STB low to resume high-speed operation.
(2) Robust Bus Interface Protection
CANH/CANL Voltage Range: –40 V to +40 V—survives automotive transients like reverse battery, load dump, and ESD.
Built-in Protections:
Thermal shutdown (>165°C junction temperature)
Overcurrent/short-circuit protection (current-limited drivers)
Dominant timeout (300–700 μs) prevents bus lock-up from stuck-low TXD
(3) Unpowered Nodes Are Bus-Invisible
When VCC = 0 V, CANH/CANL go high-impedance, ensuring unpowered nodes do not load or disturb the bus—ideal for hot-plug or multi-supply systems.
(4) SPLIT Pin Enhances EMC
SPLIT outputs ~0.5×VCC as a common-mode reference. Connect a split termination (two 30 Ω resistors from CANH and CANL to SPLIT) to suppress common-mode noise and improve high-speed signal integrity.
(5) Typical Application Circuit
Termination: 120 Ω resistor between CANH and CANL at both ends of the bus.
Power Decoupling: Place 100 nF ceramic + 10 μF electrolytic capacitor close to VCC/GND pins.
Optional Bus Protection: Add TVS diodes (e.g., SMBJ33A) on CANH/CANL for ±200 V transient suppression (device rated for ±200 V transients).
(6) Logic-Level Compatibility
TXD/RXD are 5V TTL/CMOS compatible—directly interfaces with 5V MCUs.
Input thresholds: VIH ≥ 2 V, VIL ≤ 0.8 V.
3. Typical Applications
Automotive: Body Control Modules (BCM), instrument clusters, ECU networking
Industrial: PLCs, sensor/actuator fieldbus networks
Commercial EVs: BMS-to-motor controller communication in buses/trucks
Building automation and smart grid devices
4. Summary
The TD1040 delivers a robust, ISO 11898-2-compliant physical layer with 1 Mbps speed, comprehensive protection, ultra-low standby current, and excellent EMC performance. By properly utilizing the STB control, SPLIT-based termination, and bus/power protection, designers can build highly reliable, low-power, and noise-immune CAN communication systems for demanding automotive and industrial environments.
