1 Hardware Overview 1.2 System Unit Components
16 Satellite M40/M45 TECRA A4 dynabook Vx/4 Maintenance Manual
Audio Controller
The AD1981B integrated audio controller supports multimedia. The sound system
feature contains the following:
y Variable Sample Rate Audio
y External Audio Power –Down Control
y Integrated Stereo Headphone Amplifier
y Stereo Full-Duplex Codec
y 20-Bit PCM DAC
y Dual MIC Input with Built-In Programmable Preamp
y High Quality CD Input with Ground Sense.
KBC/EC (Keyboard Controller/Embedded Controller)
A single LPC 47N249 chip is used to serve as KBC/ EC and Super IO.
y KBC
− Scan controller function
− Interface controller function
y EC
− Power supply sequence control
− Overheat shutdown support
− LED control
− Beep control
− Device ON/OFF
− Cooling fan speed control
− Universal I/O port
− Battery capacity check
− Flash memory reprogramming function
− EC access interface
− I2C communication control
Battery EE PROM
y 24C02 equivalent (128 words x 16 bits, I2C interface) integrated in the battery pack
− Storing records of battery use