MC34825EPR2 Freescale Semiconductor, MC34825EPR2 Datasheet - Page 19

• Manufacturer Part Number: MC34825EPR2
• Description: IC USB MINI UNIV CHARGING 20QFN
• Manufacturer: Freescale Semiconductor
• Type: USB Interface ICr

Specifications of MC34825EPR2

• Controller Type: USB Peripheral Controller
• Interface: Micro-USB
• Voltage - Supply: 2.7 V ~ 5.5 V
• Current - Supply: 100mA
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 20-UFQFN Exposed Pad
• Usb Version: 2.0
• No. Of Ports: 1
• Supply Voltage Range: 2.7V To 5.5V
• Operating Temperature Range: -40°C To +85°C
• No. Of Pins: 20
• Msl: MSL 3 - 168 Hours
• Peak Reflow Compatible (260 C): Yes
• Rohs Compliant: Yes
• Leaded Process Compatible: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

pin and the ground (R
accessory detection and recognition. The nominal ID
resistance that the 34825 supports is listed in
as in
resistance recognition and the corresponding ADC results vs.
the R
to have 1% or better accuracy for the ADC to recognize
successfully.
detachment detection. When no accessory is attached, the ID
pin is floating. An ID_FLOAT bit in the Status register stays in
the value of 1. When a resistor less than or equal to 1.0 MΩ
is connected between the ID line and the ground, the
ID_FLOAT bit changes to 0. When the resistor is removed,
ID_FLOAT bit returns to 1. A falling-edge of the ID_FLOAT bit
represents the attachment of the accessory and the ADC is
enabled to measure the ID resistance. The ADC Result
register has the identification result of the R
Analog Integrated Circuit Device Data
Freescale Semiconductor
The ID detection relies on the resistance between the ID
A comparator monitors the ID pin for attachment and
Table
ID
are also listed in
21. The 34825 offers a 5-bit ADC for the
ID
No
) inside the accessory for the
Table
VBUS_DET bit
_SHORT bit
Set DP/DM
ID_FLOAT
VBUS=0V
Applied?
DP->DM
SHORT?
VBUS
=1?
Set
Yes
Yes
No
6. The resistors are required
Figure 14. Detailed Accessory Identification Flow Diagram
Yes
No
Yes
USB_CHG bit
ID_GND bit
SHORT?
DM->DP
Set
Set
No
ID
Table 6
ACTIVE = 0
, as given in
Yes
No
USB switches
ID shorted
to GND?
TD time
Turn on
1000x?
ADC =
as well
Delay
ID DETECTION
No
Yes
Yes
Yes
ADC RESULT
ID_FLOAT bit
VBUS_DET
ATTACH bit
Key Value?
ACTIVE bit
ID Float?
switches
ID Float
00000?
Turn on
0111x?
ADC =
ADC =
ADC =
UART
Table
detachment of the accessory.
between ‘00001’ to ‘01101’ are assigned to 13 remote-control
keys for the two accessories that support remote controllers,
as listed in
assigned to various accessories. If the ADC result is one of
the remote control key values in the identification flow, it is
possible that the remote control key is stuck when the
accessory is attached.
resolve such an issue. As shown in the
key is recognized but is released within 1.5s, the identification
flow will return to re-detect the ID line; Otherwise, the
ATTACH bit will be set and the ADC Result register has the
key result. After the key is released, the 34825 will detect the
ID resistance value again. If the accessory is still connected,
the ATTACH bit is set again and the ADC result has the ID
resistor value of the accessory.
Clear
Set
=1?
Set
Set
Yes
No
No
No
No
The ADC results are broken into two groups. The values
A special Stuck Key Identification flow is designed to
6. A rising edge of the ID_FLOAT bit represents the
Yes
Yes
No
No
Table
ID_FLOAT bit
Key Released
DETACH bit
within 1.5s?
ID Float?
Set
Set
Yes
Yes
21. The rest of the ADC results are
No
ATTACH bit
Released?
FUNCTIONAL DEVICE OPERATION
Key
Set
Yes
ACCESSORY IDENTIFICATION
No
Figure
14, if the stuck
34825
19