MAX14550E Maxim, MAX14550E Datasheet - Page 10

• Manufacturer Part Number: MAX14550E
• Description: The MAX14550E is a USB Hi-Speed analog switch with a USB host charger (dedicated charger) identification circuit
• Manufacturer: Maxim

USB Host Charger Identification Analog Switch
Figure 4. Operation with External Resistors
The MAX14550E features autodetection mode for dedi-
cated chargers and USB masters. CB0 and CB1 must
both be set low to activate autodetection mode.
In autodetection mode, the MAX14550E initially connects
the resistor network to DP and DM. The MAX14550E
monitors the voltage at DM to determine the type of
device attached. If the voltage at DM is 2.1V (typ) or
higher, the voltage stays as is.
If the voltage at DM is below the 2.1V (typ) threshold,
the internal switch disconnects DP from the resistor
network and DM. DP and DM are shorted together. The
MAX14550E then monitors the voltage at DM to deter-
mine when to reconnect the resistor network. If the volt-
10
43.2kI
49.9kI
49.9kI
75kI
5.0V
RDP
RDM
0.4V
GND
RM2
RP2
V
V
CC_SW
CC_SW
0.1µF
RP1
RM1
Autodetection
3.3V TO 5.0V
V
CC
2.1V
MAX14550E
R
S
age at DM > 0.35V (typ), the short remains connected. If
the voltage at DM drops below 0.35V (typ), the short is
removed and the resistor network is reconnected to DP
and DM.
DP and DM feature a 100Fs (typ) debounce time to reject
transients.
ESD performance depends on a variety of conditions.
Contact Maxim for a reliability report that documents test
setup, test methodology, and test results.
The Air-Gap test involves approaching the device with a
charged probe. The Contact-Discharge method connects
the probe to the device before the probe is energized.
TDM
Q
D-
0.4V
TRANSCEIVER
USB
D+
TDP
500kI
CBO
CONTROL
LOGIC
CB1
PROTECTION
ESD
ESD Test Conditions
DM
DP
CB0 AND CB1
00 - AUTO MODE
01 - FORCE SHORT
10 - FORCE RESISTOR
11 - TDP = DP, TDM = DM
D+
D-
CONNECTOR
USB