
NCN1188
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11
DETAILED APPLICATION
The NCN1188 voltage range and high bandwidth
performance permits switching between audio, video and
data signals on a portable device. It allows D+ and D data
pins of a single USB connector to be used for many different
functions as pictured by Figure
1: USB 2.0 data transfer with backward compatibility to
USB 1.1 and USB 1.0
MHL high definition video transfer up to 3 Gbps for
1080p resolutions
Audio headset with negative voltage capability to
connect true ground audio amplifier
UART to address programming and testing in factory
Any other analog or digital data sources within the
recommended operating conditions
Figures
26 and
27 detail two design examples with
different switching combinations using NCN1188.
In the first example shown in Figure
26, the device is
directly supplied from a single LiIon battery, typically
from 3.0 V to 4.2 V. The NCN1188 switch connects a 5pin
microUSB connector to a Communication Processor, an
MHL Application Processor, and the Audio Management IC
headphone amplifier. Each function is active pending on
power management IC accessory detection to control IN1
and IN2. This decision is usually made on the D, D+, and
ID pins to detect and differentiate accessory types such as
USB cable, USB to HDMI MHL cable and microUSB
stereo headset.
For solutions related to portable devices accessory
detection, contact your ON Semiconductor Field
Applications Engineer.
The USB 3.0 MicroB receptacle may be considered a
combination of the USB 2.0 MicroB interface and USB 3.0
SuperSpeed contacts and maintains backward compatibility
with USB 2.0 MicroB plugs. As a consequence, the
NCN1188’s USB 2.0 capability is fully compatible to the
USB 3.0 MicroB receptacle, as well as USB 2.0
accessories.
VBUS
USB2.0_MICROB
1
2
3
4
5
D+
D
ID
USB 2.0
Communication Processor
NCN1188
10
D+
IN2
7
IN1
11
DP
1
DN
5
HDP
2
HDN
4
8
D
GND
9
VCC
3
AUDN
6
AUDP
12
USB
USB+
MHL
MHL+
Vcc_core
Vcc_IO
Vcc_core
Audio Right
Audio Left
Single Cell Liion
3.0V to 4.2V
Battery Charger
Headset
Amps
Audio Management IC
Accessory Detect
100n
CBUS
ID_out
ID_in
Control
D+
D
ID
Power Management IC
HD
Video
MHL Application Processor
Figure 26. Schematic Example for USB 2.0, MHL, and Audio Combination; NCN1188 being supplied from battery