NEC PD703114 User Manual page 599

14.1 Features
• Two power supplies, one for the internal CPU and one for the peripheral interface, are not necessary.
• A 5 V single power supply system can be configured by connecting an N-ch transistor (2SD1950 (VL standard
product, surface mount type) or 2SD1581 (independent type) is recommended).
• If a 3.3 V power supply is available, it can be directly connected to the REGIN pin.
14.2 Functional Outline
The V850E/IA2 has an internal regulator that can be used to configure a 5 V single power supply system.
To use this regulator, connect an N-ch transistor (2SD1950 (VL standard product, surface mount type) or 2SD1581
(independent type) is recommended) to the REGOUT pin, and the REGIN pin to CV
the regulator output (refer to 14.3 Connection Example). If two power supplies (5 V system for the peripheral
interface and 3.3 V system for the internal CPU) are available on the system, the regulator can be stopped by the
regulator control register (REGC).
The regulator always operates in each operation mode (normal operation, HALT, IDLE, and software STOP mode).
If the 3.3 V power supply is provided separately, setting REGC = 01H suppresses the current consumption (several
µ
10 A) of the on-chip regulator.
CHAPTER 14 REGULATOR
User's Manual U15195EJ5V0UD
via a capacitor for stabilizing
SS
599