AVR524: Migration from ATmega64 to ATmega64A 8-bit Microcontrollers 1 Introduction Application Note In order to optimize the manufacturing process and to further reduce current consumption, an optimized version of ATmega64 has been introduced. The ATmega64A is a functionally identical, drop-in replacement for the ATmega64. All devices are subject to the same qualification process and same set of production tests, but as the manufacturing process is not the same some electrical characteristics differ. ATmega64 and ATmega64A have separate datasheets. This application note outlines the differences between the two devices and the datasheets. There is also a detailed change log to assist the user at the end of the ATmega64A datasheet. Remember to always use the latest revision of the device datasheet. Minor differences in typical characteristics are not discussed in this document as long as the low and high limits remain the same. For detailed information about the typical characteristics, see sections “Electrical Characteristics” and “Typical Characteristics” of the device datasheets. Note: This application note serves as a guide to ease migration. For complete device details, always refer to the most recent version of the ATmega64A datasheet. Rev. 8165A-AVR-03/09 2 Changes in Characteristics This section outlines major differences in characteristics that may have an effect on the application in which the device is used. For detailed information, refer to the most recent version of the device datasheets. 2.1 Current Consumption Active and Idle mode current consumption of the device has been reduced significantly. The tables below present typical current consumption figures at room temperature. All values are taken from device datasheets, unless otherwise noted. Table 2-1. Typical Current Consumption of Device at Room Temperature Mode Active Idle Reset Condition ATmega64 ATmega64A Change VCC=3V, f=4 MHz 4.1 mA 2.5 mA - 39% VCC=5V , f=8 MHz 15,5 mA 9 mA - 42% VCC=3V, f=4 MHz 2 mA 0.7 mA - 65% VCC=5V , f=8 MHz 8 mA 2.8 mA - 65% VCC=3V, f=4 MHz 3 mA 2.5 mA - 17% VCC=5V , f=8 MHz 13 mA 7.8 mA - 40% 2.2 VOL Levels In Table 2-2 are listed differences in output low and high voltage levels. Table 2-2. Changes to VOL and VOH Levels Symbol VOL Parameter Output Low Voltage (Ports A - G) Condition ATmega64 ATmega64A Units Min Max Min Max IOL=20mA, VCC=5V - 0.7 - 0.9 V IOL=10mA, VCC=3V - 0.5 - 0.6 V 3 Datasheet Changes For a summary of changes, see the datasheet revision history at the end of the ATmega64A datasheet. 2 AVR524 8165A-AVR-03/09 Disclaimer Headquarters International Atmel Corporation 2325 Orchard Parkway San Jose, CA 95131 USA Tel: 1(408) 441-0311 Fax: 1(408) 487-2600 Atmel Asia Unit 1-5 & 16, 19/F BEA Tower, Millennium City 5 418 Kwun Tong Road Kwun Tong, Kowloon Hong Kong Tel: (852) 2245-6100 Fax: (852) 2722-1369 Atmel Europe Le Krebs 8, Rue Jean-Pierre Timbaud BP 309 78054 Saint-Quentin-enYvelines Cedex France Tel: (33) 1-30-60-70-00 Fax: (33) 1-30-60-71-11 Atmel Japan 9F, Tonetsu Shinkawa Bldg. 1-24-8 Shinkawa Chuo-ku, Tokyo 104-0033 Japan Tel: (81) 3-3523-3551 Fax: (81) 3-3523-7581 Technical Support [email protected] Sales Contact www.atmel.com/contacts Product Contact Web Site http://www.atmel.com/ Literature Request www.atmel.com/literature Disclaimer: The information in this document is provided in connection with Atmel products. No license, express or implied, by estoppel or otherwise, to any intellectual property right is granted by this document or in connection with the sale of Atmel products. EXCEPT AS SET FORTH IN ATMEL’S TERMS AND CONDITIONS OF SALE LOCATED ON ATMEL’S WEB SITE, ATMEL ASSUMES NO LIABILITY WHATSOEVER AND DISCLAIMS ANY EXPRESS, IMPLIED OR STATUTORY WARRANTY RELATING TO ITS PRODUCTS INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. IN NO EVENT SHALL ATMEL BE LIABLE FOR ANY DIRECT, INDIRECT, CONSEQUENTIAL, PUNITIVE, SPECIAL OR INCIDENTAL DAMAGES (INCLUDING, WITHOUT LIMITATION, DAMAGES FOR LOSS OF PROFITS, BUSINESS INTERRUPTION, OR LOSS OF INFORMATION) ARISING OUT OF THE USE OR INABILITY TO USE THIS DOCUMENT, EVEN IF ATMEL HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. Atmel makes no representations or warranties with respect to the accuracy or completeness of the contents of this document and reserves the right to make changes to specifications and product descriptions at any time without notice. Atmel does not make any commitment to update the information contained herein. Unless specifically provided otherwise, Atmel products are not suitable for, and shall not be used in, automotive applications. Atmel’s products are not intended, authorized, or warranted for use as components in applications intended to support or sustain life. © 2009 Atmel Corporation. All rights reserved. Atmel®, Atmel logo and combinations thereof, AVR® and others, are the registered trademarks or trademarks of Atmel Corporation or its subsidiaries. Other terms and product names may be trademarks of others. 8165A-AVR-03/09