R5F72115D160FPV datasheet(1106/1228 Pages) RENESAS

1106 / 1228 page

Section 27 Electrical Characteristics

Rev. 2.00 May. 08, 2008 Page 1082 of 1200

REJ09B0344-0200

27.2

Power-on/Power-off Sequence

Power-on/power-off sequence and their recommended values are shown below.

AVcc (5.0-V power supply)

AVcc Min. voltage (4.5 V)

VccQ (3.3-V power supply)

VccQ Min. voltage (3.0 V)

Vcc, PLLVcc (1.5-V power supply)

Vcc, PLLVcc Min. voltage (1.4 V)

tunc

GND

Pins status

undefined

tunc

Pins status

undefined

Normal operation period

Figure 27.1 Power-on/Power-off Sequence

Table 27.2

Recommended Time for Power-on/Power-off Sequence

Item

Symbol

Maximum Allowance Value

Unit

Undefined time

tunc

100

Note:

VccQ

≥ Vcc = PLLVcc is recommended. Either VccQ, Vcc, or PLLVcc power supply can be

turned on or off first, though, an undefined period appears until Vcc rises to the Min. voltage

or after Vcc passes the Min. voltage. During these periods, pin or internal states become

undefined. Design the system so that such undefined states do not cause a system

malfunction. To avoid an increase in the current consumption during the undefined period

at power-on, it is recommended that VccQ, Vcc, and PLLVcc be turned on simultaneously.

This undefined period can be eliminated by turning on the power supplies in the order

shown in figure 27.2.

R5F72115D160FPV Datasheet(PDF) 1106 Page - Renesas Technology Corp