APPLICATION NOTE ATA6621, ATA6621N, ATA6622, ATA6622C, ATA6624, ATA6624C, ATA6626, ATA6626C Development Board ATA6621/22/24/26 Introduction The development board for the Atmel ATA6621/22/24/26 (ATA6621-EK, ATA6622-EK, ATA6624-EK, ATA6626-EK) is designed to give designers a quick start with the ICs and for prototyping and testing of new LIN designs. The Atmel ATA6621, Atmel ATA6622, Atmel ATA6624 and Atmel ATA6626 are system basis chips (SBCs) with fully integrated LIN transceiver, window watchdog with adjustable trigger times and low-drop voltage regulator providing 5V/85mA (3.3V/85mA for the Atmel ATA6622). The output current of the regulator can be boosted by using an external NPN transistor. The Atmel ATA6622 and the Atmel ATA6624 are totally pin- and function-compatible, the only difference between these circuits is the regulators output voltage. The ATA6626 has the same functionality as the ATA6624 without TXD time-out timer. The ATA6626 is able to switch the LIN pin without any time limitation to dominant level via the TXD input and is therefore particularly suited for low data rates. The Atmel ATA6621 differs in a few more ways an initial overview of these differences starts with the different pins listed in Table 1. Table 1. Overview of Pin Differences Pin No. Atmel ATA6621 ATA6622/24/26 2 PTRIG GND 6 Not connected GND 8 Not connected GND 10 Not connected INH 16 GND KL 15 17 TEMP GND 4970C-AUTO-06/15Figure 1. ATA6621/22/24/26 Development Board Another difference is unequal watchdog timing (see Section 1.3 on page 4). The combination of the features included in the Atmel ATA6621/22/24/26 makes it possible to develop simple, but powerful and cheap, slave nodes in LIN-bus systems. The ICs are 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 and Silent Mode guarantee a very low current consumption. This document has been developed to give the user an easy start with the development board of the Atmel ATA6621/22/24/26. For more detailed information about the use of these devices themselves, refer to the corresponding datasheets. Development Board Features The development board for the Atmel ATA6621/22/24/26 supports the following features: All necessary components to put the Atmel ATA6621/22/24/26 in operation are included Placeholders for some optional components for extended functions included All pins easily accessible Easily adaptable watchdog times by replacing a resistor Possibility to place an external NPN transistor for boosting up the output current of the voltage regulator (jumper J1) Possibility of selecting between master or slave operation (mounting D3 and R4) 2 ATA6621/22/24/26 APPLICATION NOTE 4970CAUTO06/15