HGA1050M/TR

HGA1050 High speed CAN transceiver FEATURES GENERAL DESCRIPTION • Fully compatible with the “ISO 11898” standard The HGA1050 is the interface between the CAN protocol controller and the physical bus. The device provides differential transmit capability to the bus and differential receive capability to the CAN controller. • High speed (up to 1 Mbaud) • Transmit Data (TXD) dominant time-out function • Bus lines protected against transients in an automotive environment • Silent mode in which the transmitter is disabled The HGA1050 is the successor to the PCA82C250 high speed CAN transceiver. The most important improvements are: • Differential receiver with wide common-mode range for high ElectroMagnetic Immunity (EMI) • Much lower ElectroMagnetic Emission (EME) due to optimal matching of the CANH and CANL output signals • Input levels compatible with 3.3 V devices • Improved behaviour in case of an unpowered node. • Thermally protected • Short-circuit proof to battery and ground • An unpowered node does not disturb the bus lines • At least 110 nodes can be connected. QUICK REFERENCE DATA SYMBOL PARAMETER VCC supply voltage CONDITIONS MIN. MAX. UNIT 4.75 5.25 V 0 < VCC < 5.25 V; no time limit −27 +40 V VCANH DC voltage at CANH VCANL DC voltage at CANL Vi(dif)(bus) differential bus input voltage dominant 1.5 3 V tPD(TXD-RXD) propagation delay TXD to RXD; see Fig.4 VS = 0 V − 250 ns Tamb operating ambient temperature −40 +125 °C http://www.hgsemi.com.cn 1 2019 OCT HGA1050 BLOCK DIAGRAM VCC handbook, full pagewidth S 3 8 60 µA VCC GND TEMPERATURE PROTECTION 200 µA TXD TXD DOMINANT TIME-OUT TIMER 1 DRIVER 7 VCC RXD 4 RECEIVER 0.5VCC 25 kΩ GND GND 6 Vref CANH 25 kΩ 5 REFERENCE VOLTAGE CANL HGA1050 2 GND Fig.1 Block diagram. PINNING SYMBOL TXD PIN DESCRIPTION 1 transmit data input; reads in data from the CAN controller to the bus line drivers SOP8/DIP8 handbook, halfpage GND 2 ground VCC 3 supply voltage TXD 1 RXD 4 receive data output; reads out data from the bus lines to the CAN controller GND 2 Vref 5 reference voltage output CANL 6 LOW-level CAN bus line CANH 7 HIGH-level CAN bus line S 8 select input for high speed mode/silent mode http://www.hgsemi.com.cn 8 S 7 CANH HGA1050 VCC 3 6 CANL RXD 4 5 Vref Fig.2 Pin configuration. 2 2019 OCT HGA1050 FUNCTIONAL DESCRIPTION Control line S (pin 8) allows two operating modes to be selected; high speed mode or silent mode. The HGA1050 is the interface between the CAN protocol controller and the physical bus. It is primarily intended for high speed automotive applications using baud rates from 40 kbaud up to 1 Mbaud. It provides differential transmit capability to the bus and differential receiver capability to the CAN protocol controller. It is fully compatible to the “ISO 11898” standard. High speed mode is the normal operating mode and is selected by connecting pin S to ground. It is the default mode if pin S is unconnected. In the silent mode, the transmitter is disabled. All other IC functions continue to operate. The silent mode is selected by connecting pin S to VCC. A current-limiting circuit protects the transmitter output stage from damage caused by accidental short-circuit to either positive or negative battery voltage, although power dissipation increases during this fault condition. A ‘TXD Dominant Time-out’ timer circuit prevents the bus lines being driven to a permanent dominant state (blocking all network communication) if TXD is forced permanently LOW by a hardware and/or software application failure. The timer is triggered by a negative edge on TXD. If the duration of the LOW-level on TXD exceeds the internal timer value, the transmitter is disabled, driving the bus into a recessive state. The timer is reset by a positive edge on TXD. A thermal protection circuit protects the IC from damage by switching off the transmitter if the junction temperature exceeds a value of approximately 165 °C. Because the transmitter dissipates most of the power, the power dissipation and temperature of the IC is reduced. All other IC functions continue to operate. The transmitter off-state resets when TXD goes HIGH. The thermal protection circuit is particularly needed when a bus line short-circuits. The CANH and CANL lines are protected from automotive electrical transients (according to “ISO 7637”; see Fig.6) and are also protected from Electro-Static-Discharge (ESD) of up to 4 kV from the human body. Table 1 Function table of the CAN transceiver (X = don’t care) VCC TXD S 4.75 to 5.25 V 0 0 (or floating) HIGH LOW dominant 0 4.75 to 5.25 V X 1 0.5 × VCC 0.5 × VCC recessive 1 4.75 to 5.25 V 1 (or floating) X 0.5 × VCC 0.5 × VCC recessive 1