Although Stellaris microcontrollers have generous internal SRAM capabilities, certain applicationsmay have data storage requirements that exceed the 8 KB limit of the Stellaris LM3S8xx seriesdevices. Since microcontrollers do not have an external parallel data-bus, serial memory optionsmust be considered. Until recently, the ubiquitous serial EEPROM/flash device was the only serialmemory solution. The major limitations of EEPROM and flash technology are slow write speed, slowerase times, and limited write/erase endurance.Recently, serial SRAM devices have become available as a solution for high-speed dataapplications. The N256S08xxHDA series of devices, from AMI Semiconductor, offer 32 K x 8 bits oflow-power data storage, a fast Serial Peripheral Interface (SPI) serial bus, and unlimited write cycles.The parts are available in 8-pin soic and compact TSSOP packages.
The MC68HC05K0 is a low cost, low pin countsingle chip microcomputer with 504 bytes of userROM and 32 bytes of RAM. The MC68HC05K0 isa member of the 68HC05K series of devices whichare available in 16-pin DIL or soic packages.It uses the same CPU as the other devices in the68HC05 family and has the same instructions andregisters. Additionally, the device has a 15-stagemulti-function timer and 10 general purposebi-directional I/0 lines. A mask option is availablefor software programmable pull-downs on all ofthe I/O pins and four of the pins are capable ofgenerating interrupts.The device is ideally suited for remote-controlkeyboard applications because the pull-downs andthe interrupt drivers on the port pins allowkeyboards to be built without any externalcomponents except the keys themselves. There isno need for external pull-up or pull-down resistors,or diodes for wired-OR interrupts, as these featuresare already designed into the device.
Full compliance with the USB Specification v1.1 and USB CDC v1.1
Support the RS232 Serial interface
Support automatic handshake mode
Support Remote wake-up and power management
256 bytes buffer each for upstream and downstream data flow
Support default ROM or external EEPROM for device configuration
On chip USB transceiver
On chip crystal oscillator running at 12M Hz
Supports Windows 98/SE, ME, 2000, XP, Windows CE3.0, CE .NET, Linux, and Mac OS
28 Pins soic package
28
The SP486 and SP487 are low–power quad differential line drivers meeting RS-485 and RS-422
standards. The SP486 features a common driver enable control the SP487 provides independent
driver enable controls for each pair of drivers. Both feature tri–state outputs and wide
common–mode input range. Both are available in 16–pin plastic DIP and soic packages.
The AT24C512 provides 524,288 bits of serial electrically erasable and programmable
read only memory (EEPROM) organized as 65,536 words of 8 bits each. The device鈥檚
cascadable feature allows up to four devices to share a common two-wire bus. The
device is optimized for use in many industrial and commercial applications where lowpower
and low-voltage operation are essential. The devices are available in spacesaving
8-pin PDIP, 8-lead EIAJ soic, 8-lead JEDEC soic, 8-lead TSSOP, 8-lead
Leadless Array (LAP), and 8-lead SAP packages. In addition, the entire family is available
in 2.7V (2.7V to 5.5V) and 1.8V (1.8V to 3.6V) versions.
