MC68HC908JW32_09 Datasheet, PDF (148/232 Pages) Freescale Semiconductor, Inc – M68HC08 Microcontrollers

USB 2.0 FS Module
11.3 USB Module Architecture
3.3V
3.3V
Regulator
D+
D–
USB
Control
Logic
Endpoint
Buffer
USB
Endpoint
Controller
USB
Request
Processor
System Bus
Figure 11-1. USB Module Block Diagram
The USB module block diagram is shown in Figure 11-1. The module involves six major blocks - USB
transceiver, USB control logic, USB request processor, USB endpoint controller and USB Endpoint
buffer.
11.3.1 USB Transceiver
The USB transceiver is electrically compliant to the Universal Serial Bus Specification 2.0. The on-chip
3.3V regulator provides a stable power source for the termination pull-up resistor. Full speed devices are
terminated with the pull-up resistor on the D+ line.
MC68HC908JW32 Data Sheet, Rev. 6
148
Freescale Semiconductor