ATA6663/ATA6664 Single-LIN Bus Transceiver in 3x3mm DFN Package
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Features ● Operating range from 5V to 27V ● Baud rate up to 20Kbaud ● Improved slew rate control according to LIN specification 2.0, 2.1 and SAEJ2602-2 ● Fully compatible with 3.3V and 5V devices ● Atmel® ATA6663: TXD Time-out Timer, Atmel ATA6664: No TXD Time-out Timer ● Normal and Sleep Mode ● Wake-up capability via LIN bus (90µs dominant) ● External wake-up via WAKE Pin (35µs low level) ● INH output to control an external voltage regulator or to switch the master pull-up ● Very low standby current during Sleep Mode (10µA) ● Wake-up source recognition ● Bus pin short-circuit protected versus GND and battery ● LIN input current < 2µA if VBAT is disconnected ● Overtemperature protection ● High EMC level ● Interference and damage protection according to ISO/CD 7637 ● Fulfills the OEM “Hardware Requirements for LIN in Automotive Applications Rev.1.1” ● Packages: SO8, DFN8 Description The Atmel ATA6663 is a fully integrated LIN transceiver complying with the LIN specification 2.0, 2.1 and SAEJ2602-2. The Atmel ATA6664 is an identical version, the only difference is that the TXD-dominant Time-out function is disabled so the device is able to send a static low signal to the LIN bus. It interfaces the LIN protocol handler and the physical layer. The device is designed to handle the low-speed data communication in vehicles, for example, in convenience electronics. Improved slope control at the LIN driver ensures secure data communication up to 20Kbaud. Sleep Mode guarantees minimal current consumption even in the case of a floating bus line or a short circuit on the LIN bus to GND. The ATA6663/ATA6664 feature advanced EMI and ESD performance.

Short circuit and overtemperature protection Slew rate control Wake-up timer Standby mode Pin Configuration Figure 1-1. Pinning SO8, DFN8 RXD EN WAKE TXD Enables normal mode; when the input is open or low, the device is in sleep mode High voltage input for local wake-up request. If not needed, connect directly to VS Transmit data input; active low output (strong pull-down) after a local wake-up request Ground, heat sink Battery supply Battery-related inhibit output for controlling an external voltage regulator or to switch-off the LIN master pull-up resistor; active high after a wake-up...

Functional Description Physical Layer Compatibility Since the LIN physical layer is independent from higher LIN layers (e.g., the LIN protocol layer), all nodes with a LIN physical layer according to LIN2.x can be used along with LIN physical layer nodes, which are according to older versions (i.e., LIN1.0, LIN1.1, LIN1.2, LIN1.3), without any restrictions. Supply Pin (VS) Undervoltage detection is implemented to disable transmission if VS falls to a value below 5V in order to avoid false bus messages. After switching on VS, the IC switches to fail-safe mode and INHIBIT is switched on. The...

Inhibit Output Pin (INH) This pin is used to control an external voltage regulator or to switch on/off the LIN Master pull-up resistor in case the device is used in a Master node. The inhibit pin provides an internal switch towards pin VS which is protected by temperature monitoring. If the device is in normal or fail-safe mode, the inhibit high-side switch is turned on. When the device is in sleep mode, the inhibit switch is turned off, thus disabling the voltage regulator or other connected external devices. A wake-up event on the LIN bus or at pin WAKE will switch the INH pin to the VS...

Table of Operation Modes High, except after wake-up High ohmic Wake-up events from sleep mode: ● LIN bus Figure 2-1 on page 4, Figure 2-2 on page 5 and Figure 2-5 on page 8 show the details of wake-up operations. Remote Wake-up via Dominant Bus State A voltage lower than the LIN pre-wake detection VLINL at pin LIN activates the internal LIN receiver and starts the wake-up detection timer. A falling edge at pin LIN, followed by a dominant bus level VBUSdom maintained for a certain time period (> tBUS) and a rising edge at pin LIN results in a remote wake-up request. The device switches to...

In sleep mode the device has a very low current consumption, even during short-circuits or floating conditions on the bus. A floating bus can arise if the Master pull-up resistor is missing, e.g., in case it is switched off when the LIN Master is in sleep mode or if the power supply of the Master node is switched off. To minimize the current consumption IVS during voltage levels at the LIN-pin below the LIN pre-wake threshold, the receiver is activated only for a specific time tmon. If tmon elapses while the voltage at the bus is lower than pre-wake detection low (VLINL) and higher than the...

If the Atmel® ATA6663/ATA6664 is in sleep mode and the voltage level at the LIN is in dominant state (VLIN < VBUSdom) for a time period exceeding tmon (during a short circuit at LIN, for example), the IC switches back to sleep mode. The VS current consumption then consists of IVSsleep plus ILINWAKE. After a positive edge at pin LIN the IC switches directly to fail-safe mode (see Figure 2-4). Figure 2-4. Short Circuit to GND on the LIN Bus During Sleep Mode VLINL LIN dominant state VBUSdom tmon tmon Sleep Mode Int. Pull-up Resistor RLIN Wake-up Detection Phase Sleep Mode Fail-safe Mode Local...

Figure 2-5. Wake-up from Wake-up Switch State change TXD weak pull-down resistor Weak pull-down Wake filtering time tWAKE Voltage regulator Regulator wake-up time delay EN Node in operation EN High Node in sleep state Microcontroller start-up delay time Wake-up Source Recognition The device can distinguish between a local wake-up request (pin WAKE) and a remote wake-up request (LIN bus). The wake-up source can be read at pin TXD in fail-safe mode. If an external pull-up resistor (typically 5kΩ) has been added on pin TXD to the power supply of the microcontroller, a high level indicates a...

Absolute Maximum Ratings Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress rating only and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Parameters VS - Continuous supply voltage Wake DC and transient voltage (with 2.7kΩ serial resistor) - Transient voltage according to ISO7637 (coupling 1nF) LIN - DC voltage -...