Datasheet

Table Of Contents
Section 15 Universal Serial Bus Interface (USB)
REJ09B0140-0900 Rev. 9.00 Page 587 of 846
Sep 16, 2010
H8S/2215 Group
15.8 USB External Circuit Example
Figures 15.30 and 15.31 show the USB external circuit examples when the on-chip transceiver is
used. Figures 15.32 and 15.33 show the USB external circuit examples when an external
transceiver is used.
Regulator
0: Bus-powered mode
Internal transceiver
VCC
1.5 kΩ
DrVCC
(3.3 V)
VCC
(3.3 V)
VBUS
(5 V)
USD+ USD-
D+ D-
DrVSS
GND
UBPMVBUS
VCC
(3.3 V)
24 Ω24 Ω
VSS
USB connector
*
1
USB
Step-down to the operating voltage VCC (3.3 V) of this LSI.
To protect the LSI, voltage applicable IC such as HD74LV-A series must be used
even when the system power is turned off.
In HD64F2215, HD64F2215R, HD64F2215T, HD6432215B, and HD6432215C,
Pxx should be assigned to an output port as the D+ pull-up control pin.
In HD64F2215U, HD64F2215RU, HD64F2215TU and HD64F2215CU, in which on-chip ROM can be
programmed by using the USB, P36 should be used as the D+ pull-up control pin.
Steps should be taken prevent noise from affecting the VBUS terminal during USB communications.
Pull-up
control external
circuit for
full speed
2.
3.
4.
*
2
Pxx
(P36)
*
3
*
4
1.Notes:
Figure 15.30 USB External Circuit in Bus-Powered Mode
(When On-Chip Transceiver Is Used)