Chapter 1 General; Features; Applications; Ordering Information - NEC switch User Manual

1.1 Features

• On-chip USB functions
• Implements a USB (Universal Serial Bus) by connecting to Hub and Host.
• Transfer speed: 1.5 Mbps (at 6.0 MHz operation with system clock)
• On-chip regulator
• Controls the USB port voltage by using a bus power supply (V
driver/receiver.
• On-chip ROM and RAM
• Internal ROM:
Flash memory (for µ PD78F9801 only): 16 KB
• Internal high-speed RAM:
• Variable minimum instruction execution time: From high-speed (0.33 µ s) to low speed (1.33 µ s) with the system
clock operating at 6.0 MHz
• 31 I/O ports
• Two serial interface channels
• USB function
• 3-wire serial I/O mode
• Three timers:
• 8-bit timer
• 8-bit timer/event counter
• Watchdog timer
• On-chip key return signal detector
• 12 vectored interrupt sources
• Power supply voltage: V
• Operating ambient temperature: T

1.2 Applications

USB keyboards, etc.

1.3 Ordering Information

Part Number
µ PD789800GB-×××-8ES
µ PD78F9801GB-8ES
Remark ××× indicates ROM code suffix.
CHAPTER 1
8 KB
256 bytes
= 4.0 to 5.5 V
DD
= –40 to +85°C (when the USB is not operating)
A
T = 0 to +70°C (when the USB is operating)
A
T = 10 to 40°C (when the flash memory is written)
A
44-pin plastic LQFP (10 × 10)
44-pin plastic LQFP (10 × 10)
User's Manual U12978EJ3V0UD
GENERAL
= 3.3 ±0.3 V) dedicated to the USB
REG
Package Internal ROM
Mask ROM
Flash memory
21