Datasheet

Analog Integrated Circuit Device Data
89 Freescale Semiconductor
MC34708
Functional Block Description
will reset to a 1, when either RESETB is valid or VBUS is invalid. This allows the VUSBEN regulator to be enabled automatically
if the VUSB regulator was disabled by software. With PUMS4:1 equal to [0100], the VUSBEN bit will be enabled in the power up
sequence.
The MC34708 also supports USB OTG mode by supplying 5.0 V to the VBUS pin. The OTGEN SPI bit along with the VUSBSEL
SPI bit, control switching the SWBST to drive VBUS in OTG mode. When OTGEN = 1 and VUSBSEL = 1, SWBST will be driving
the VBUS (switch M1 and MOTG are closed, and the M0 switch is open). When OTG mode is disabled, the switch (MOTG) from
VINUSB to VBUS will be open.
In OTG mode, the VUSB regulator is enabled by setting the VUSBEN SPI bit to a 1. When SWBST is supplying the VBUS pin
(OTG Mode), it will generate a USBDET interrupt. The USBDET interrupt while in OTG mode should not be interpreted as being
powered by the host by software.
7.8.4.2 Accessory Identification
The MC34708 monitors both the ID pin and the VBUS pin. When an accessory attachment is detected, the accessory
identification state machine will enter Active mode to start the identification flow. The ID detection state machine will determine
Table 87. VUSB/OTG Switch Configuration
Mode OTGEN VUSBSEL Switches Enabled (Closed) Switches Disabled (Open)
VUSB powered from VBUS pin
0 0 M0 M1, MOTG
VUSB powered from VINUSB pin
0 1 M1 M0, MOTG
Invalid option
1 0 - -
OTG Mode (VUSB powered from VINUSB pin and SWBST
1 1 M1, MOTG M0
Table 88. VUSB Electrical Characteristics
Characteristics noted under conditions BP = 3.6 V, V
BUS
= 5.0 V, - 40 C  T
A
 85 C, unless otherwise noted. Typical values
at BP = 3.6 V and T
A
= 25 °C under nominal conditions, unless otherwise noted.
Symbol Characteristic Min Typ Max Unit Notes
VUSB REGULATOR
V
USBIN
Operating Input Voltage Range V
INMIN
to V
INMAX
• Supplied by VBUS
• Supplied by SWBST
4.4
-
5.0
-
5.25
5.75
V
I
USB
Operating Current Load Range IL
MIN
to IL
MAX
0.0 - 100 mA
VUSB ACTIVE MODE - DC
V
USB
Output Voltage V
OUT
•V
INMIN
< V
IN
< V
INMAX
IL
MIN
< IL < IL
MA
V
NOM
- 4% 3.3 V
NOM
+ 4%
V
V
USBLOPP
Load Regulation
• 0 < IL < IL
MAX
from DM / DP, For any V
INMIN
< V
IN
< V
INMAX
- 1.0 -
mV/mA
V
USBLIPP
Line Regulation
•V
INMIN
< V
IN
< V
INMAX
, For any IL
MIN
< IL < IL
MAX
- - 20
mV
t
OFF-VUSB
Turn-off Time
• Disable to 0.8 V, per USB OTG specification parameter
VA_SESS_VLD V
IN
= V
INMIN
, V
INMAX
IL = 0
- - 1.3
sec
VUSB ACTIVE MODE - AC
VUSB
PSRR
PSRR - IL = 75% of IL
MAX
20 Hz to 20 kHz
•V
IN
= V
INMIN
+ 100 mV
- 65 -
dB