Information

VBUS
Detect
1
2
3
4
5
6
= 1 s
I
DEV_HCHG_LFS
D P _ P U L L U P
V
DM_SRC
I
DP_SINK
Charging
Host Port
Charger
Detection
Phase
T
UNIT_CON_ELAPSED
Full-
Speed
Portable
USB
Device
a t c h a rg in g h o s t p o rt.
c a u s e D + v o lt a g e t o e x c e e d V
DAT_REF
V
DM_SRC
could turn on if ground currents
I
DEV_DCHG
V B U S a t p o r ta b le
U S B d e v ice
0 m A
D+
D-
C h a rg in g h o s t: V
DAT_REF < V
D
- < V LGC
Dedicated Charging Port
C h a r g in g H o s t P o rt, F S
1 m s
T
UNIT_CON_ELAPSED
=
T
SE
Q_INIT
T
SEQ_INIT
T
DCD_DBNC
C H E C K _ D M
Dedicated Charger
C h a r g in g H o s t
D e d ic a te d C h a r g e r
C h a r g in g H o s t
T
VDPSRC_ON
T
VDPSRC_CON
T
CON_IDPSNK_DIS
T
VDMSRC_DIS
Standard host: V
D
-
< V
DAT REF
T
VDMSRC_EN
lgc_hi
lgc_lo
o ff
on
o ff
on
lgc_hi
lgc_lo
o ff
on
o ff
on
o ff
on
I
SUSP
I
DP_SRC
R
DM_DWN
V
DP_SRC
I
DM_SINK
Data Pin
Contact
Detection
Charging Port
Detection
Charger
Type
Detection
Timeout
Initial
Conditions
Figure 41-9. Full speed charger detection timing
The following table provides an overview description of the charger detection sequence
shown in the preceding figure.
Chapter 41 USB Device Charger Detection Module (USBDCD)
K20 Sub-Family Reference Manual, Rev. 2, Feb 2012
Freescale Semiconductor, Inc. 939