XR22417CV48EVB [EXAR]
USB 2.0 7-Port Hub;
| 型号： | XR22417CV48EVB |
| 厂家： | 
EXAR CORPORATION |
| 描述： | USB 2.0 7-Port Hub |
| 文件： | 总17页 (文件大小：795K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
XR22417
USB 2.0 7-Port Hub
Description
FEATURES
The XR22417 is a USB 2.0 7-port hub using Multiple Transaction
Translators (MTT) for highest possible bandwidth capability.
The upstream USB interface has an integrated USB 2.0 PHY
and device controller that is compliant with both hi-speed (480
Mbps) and full-speed (12 Mbps). The downstream PHY supports
hi-speed, full-speed and low-speed (1.5 Mbps) on each of the 7
downstream ports. Individual port activity and overall hub activity
indicators provide status outputs to control external LEDs for
each port. An external EEPROM may be used with the
XR22417 to change selected USB descriptors including the
USB vendor and product IDs, the number of downstream ports
and device serial number. Overcurrent protection and power
control for each downstream port is available in the LQFP-64
package. The XR22417 operates from a single 5V power input.
Internal regulators provide a 3.3V output which may be connected to
VCC33 power input pins. In turn a second internal regulator provides
a 1.8V output from the 3.3V input. This 1.8V output may be connected
to VCC18 power input pins.
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USB 2.0 compliant interface
Multiple transaction translators (MTT)
Regulated +3.3V output power
Individual port and hub activity
LED indicators
Individual power enables (LQFP-64)
Individual overcurrent sensing (LQFP-64)
Single 5V power input
ꢀ■
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Single 12 MHz Crystal
APPLICATIONS
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USB port expansion
Docking stations
POS terminals
Test instrumentation
Factory automation and process controls
Industrial applications
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Typical Application
USB Host
Upstream Phy
XR22417
Hub Controller
MTT
Port Routing
Downstream Phy x7
Device #1
Device #2
. . .
Device #7
Figure 1. Typical Application
REV1A
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XR22417
Absolute Maximum Ratings
Operating Conditions
Stresses beyond the limits listed below may cause
permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect
device reliability and lifetime.
Operating temperature range ........................... 0°C to 70°C
VCC5 supply voltage........................................4.4V to 5.5V
VCC33 supply voltage......................................3.0V to 3.6V
VCC18 supply voltage..................................1.62V to 1.98V
VCC5 supply voltage...................................... -0.5V to 6.0V
VCC33 supply voltage.................................... -0.5V to 4.0V
VCC18 supply voltage.................................... -0.5V to 2.5V
Input voltage
(all pins except USBD+, USBD–) ................... -0.3V to 4.0V
Input voltage (USBD+ and USBD–) ............. -0.3V to 5.75V
Junction temperature................................................. 125°C
Electrical Characteristics
Unless otherwise noted: T = 0°C to 70°C, VCC5 = 4.4V to 5.5V.
A
Conditions
Symbol
Min
Typ
Max
2.5
Units
Upstream
Port Speed
Number of Active
Downstream Ports
Downstream Ports
Device Speed
Power Consumption DC Supply Current
Suspend
None
0.6
53
63
71
67
76
87
71
167
0.6
38
45
78
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
1x Full Speed
1x High Speed
1
2
7
High Speed
2x Full Speed
1x Full Speed, 1x High Speed
2x High Speed
I
CC
7x Full Speed
7x High Speed
Suspend
2.5
None
Full Speed
1
7
1x Full Speed
7x Full Speed
REV1A
2/17
XR22417
Electrical Characteristics (Continued)
Unless otherwise noted: T = 0°C to 70°C, VCC5 = 4.4V to 5.5V.
A
Symbol
Parameter
Conditions
Min
Typ
Max
Units
Non-USB I/O Pins
V
V
V
V
Input low voltage
-0.3
2.0
0.8
5.5
0.4
V
V
IL
Input high voltage
IH
Output low voltage
I
I
= 4 mA
V
OL
OH
OL
OL
Output high voltage
Input low leakage current
Input high leakage current
Input pin capacitance
= -4 mA
2.4
V
I
I
10
10
5
μA
μA
pF
IL
IH
C
IN
USB I/O Pins(1)
3.3V Regulated Power Output
3V3_OUT
Output voltage
Max load current 100 mA
3.0
3.3
3.6
V
NOTE:
1. See USB 2.0 Specification for USB I/O pins DC Electrical Characteristics.
Pin Configuration, Top View
48
1
2
DP7
LED5
LED_CTL
TEST#/SDA
LED1/SCL
LED2
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
1
2
36
35
34
33
32
31
30
29
28
27
26
25
DM7
LED_CTL
TEST#/SDA
LED1SCL
LED2
VCC33
DP6
3
VCC33
DP6
4
3
DM6
5
DM6
4
DP5
6
GND
LED3
5
LED3
DM5
7
DP5
VCC18
8
DM5
LED4
6
VCC18
LED4
VCC33
UP_DP
UP_DM
VCC18
REXT
9
VCC33
UP_DP
UP_DM
GND
VCC5
7
10
11
12
13
14
15
16
3V3_OUT
GND
8
VCC5
9
3V3_OUT
GND
PWR3#
OVC3#
PWR4#
OVC#4
VCC33
10
11
12
VCC18
REXT
VCC33
DM4
VCC33
1V8_OUT
DP4
1V8_OUT
48-Pin LQFP
64-Pin LQFP
REV1A
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XR22417
Pin Functions
LQFP-48
Pin Number Pin Number
LQFP-64
Pin Name
Type Description
48
1
1
2
LED5
O
O
Port 5 LED indicator. May be used in conjunction with LED_CTL pin.
LED hub active indicator. May be used in conjunction with port status LEDs.
LED_CTL
Test mode enable. Active low and I2C serial data. Leave unconnected for normal device
operation if no external EEPROM is used.
2
3
TEST#/SDA
I/O OD
3
4
5
6
7
8
4
5
6
7
8
9
LED1/SCL
LED2
I/O OD Port 1 LED indicator and I2C serial clock. May be used in conjunction with LED_CTL pin.
O
O
Port 2 LED indicator. May be used in conjunction with LED_CTL pin.
Port 3 LED indicator. May be used in conjunction with LED_CTL pin.
1.8V power input.
LED3
VCC18
LED4
PWR
O
Port 4 LED indicator. May be used in conjunction with LED_CTL pin.
5V power input.
VCC5
PWR
3.3V power output from internal 5V to 3.3V regulator. Must be decoupled with minimum
of 10 µF.
9
10
-
10
11
12
13
14
3V3_OUT
GND
PWR
PWR
OD
I
Ground.
Power enable for port 3 downstream device, active low. Asserted if OVC3# input is
asserted or device is not configured.
PWR3#
OVC3#
PWR4#
-
Downstream port 3 over current indicator, active low.
Power enable for port 4 downstream device, active low. Asserted if OVC4# input is
asserted or device is not configured.
-
OD
-
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
OVC4#
VCC33
DM4
I
Downstream port 4 overcurrent indicator, active low.
3.3V power input.
15
11
12
-
PWR
I/O
Downstream port 4 USBD- data.
Downstream port 4 USBD+ data.
Ground.
DP4
I/O
GND
PWR
I/O
13
14
-
DM3
Downstream port 3 USBD- data.
Downstream port 3 USBD+ data.
3.3V power input.
DP3
I/O
VCC33
DM2
PWR
I/O
16
17
-
Downstream port 2 USBD- data.
Downstream port 2 USBD+ data.
Ground.
DP2
I/O
GND
PWR
I/O
18
19
20
21
22
23
DM1
Downstream port 1 USBD- data.
Downstream port 1 USBD+ data.
3.3V power input.
DP1
I/O
VCC33
VCC18
XTALIN
XTALOUT
PWR
PWR
I
1.8V power input.
12 MHz 50 ppm crystal input with load capacitance rating of 16-20 pF.
12 MHz crystal feedback output.
O
NOTE:
Type: I = Input, O = Output, I/O = Input/Output, PWR = Power, OD = Open-Drain.
REV1A
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XR22417
Pin Functions (Continued)
LQFP-48
Pin Number Pin Number
LQFP-64
Pin Name
GND
Type Description
24
25
32
33
PWR
PWR
Ground.
1.8V power output from internal 3.3V to 1.8V regulator. Must be decoupled with minimum
of 10 µF.
1V8_OUT
26
27
28
-
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
VCC33
REXT
VCC18
GND
PWR
I
3.3V power input.
External bias resistor. Connect 2.7kΩ 1% resistor from this pin to GND.
1.8V power input.
PWR
PWR
I/O
Ground.
29
30
31
32
33
-
UP_DM
UP_DP
VCC33
DM5
Upstream port USBD- data.
Upstream port USBD+ data.
3.3V power input.
I/O
PWR
I/O
Downstream port 5 USBD- data.
Downstream port 5 USBD+ data.
Ground.
DP5
I/O
GND
PWR
I/O
34
35
36
37
38
39
DM6
Downstream port 6 USBD- data.
Downstream port 6 USBD+ data.
3.3V power input.
DP6
I/O
VCC33
DM7
PWR
I/O
Downstream port 7 USBD- data.
Downstream port 7 USBD+ data.
Ground.
DP7
I/O
GND
PWR
External reset input, active low. Must be asserted for a minimum of 10 µS. This pin
requires an external pull-up resistor to 3.3V.
40
41
50
51
EXT_RST#
I
I
Active high, indicates connection to USB host. Must connect to VBUS power input from
USB host through a series 10kΩ resistor. A 100kΩ pull-down resistor and 100nF shunt
capacitance are also required on this pin.
VBUS_SENSE
Power enable for port 7 downstream device, active low. Asserted if OVC7# input is
asserted or device is not configured.
-
-
-
52
53
54
PWR7#
OVC7#
PWR6#
OD
I
Downstream port 7 over current indicator, active low.
Power enable for port 6 downstream device, active low. Asserted if OVC6# input is
asserted or device is not configured.
OD
-
55
56
OVC6#
VCC33
I
Downstream port 7 over current indicator, active low.
3.3V power input.
42
PWR
Power enable for port 5 downstream device. Asserted if OVC5# input is asserted or
device is not configured.
-
57
PWR5#
OD
NOTE:
Type: I = Input, O = Output, I/O = Input/Output, PWR = Power, OD = Open-Drain.
REV1A
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XR22417
Pin Functions (Continued)
LQFP-48
Pin Number Pin Number
LQFP-64
Pin Name
OVC5#
Type Description
-
-
58
59
I
Downstream port 5 over current indicator, active low.
Power enable for port 1 downstream device. Asserted if OVC1# input is asserted or
PWR1#
OD
device is not configured.
-
60
61
62
-
OVC1#
PWR2#
OVC2#
TEST1#
TEST2#
TEST3#
LED7
I
OD
I
Downstream port 1 over current indicator, active low.
-
Power enable for port 2 downstream device, active low.
Downstream port 2 over current indicator, active low.
Test input. Use pull-up resistor to 3.3V for normal operation.
Test output. Leave unconnected.
-
43
44
45
46
47
I
-
O
I
-
Test input. Use pull-up resistor to 3.3V for normal operation.
Port 7 LED Indicator. May be used in conjunction with LED_CTL pin.
Port 6 LED Indicator. May be used in conjunction with LED_CTL pin.
63
64
O
O
LED6
NOTE:
Type: I = Input, O = Output, I/O = Input/Output, PWR = Power, OD = Open-Drain.
REV1A
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XR22417
Functional Block Diagram
USB Host
XR22417
Upstream Phy
Upstream Port Controller
Hub
Activity
Indicator
Port
Indicators
LED
Controller
Hub
Controller
12
MHz
5V to 3.3V
Regulator
3.3V to 1.8V
Regulator
Oscillator
PLL (x40)
480
MHz
Power
Control
Overcurrent
Detection
Downstream Port Controller
Port Routing Switch
TT #1
TT #2
. . .
. . .
TT #7
Downstream
Phy #2
Downstream
Phy #7
Downstream
Phy #1
Device #1
Device #2
. . .
Device #7
Figure 2. Functional Block Diagram
REV1A
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XR22417
Applications Information
Functional Description
The XR22417 hub has a multiple transaction translator architecture that provides one Transaction Translator (TT)
for each of the downstream USB ports. The transaction translators allow the USB 2.0 hub to take incoming high speed
packets from the USB host on the upstream port and translate these commands, if necessary to full or low speed devices
on any of the 7 downstream ports. The MTT architecture allows for higher bandwidth as the 7 individual ports are not
constrained by a shared resource.
USB Interface
The hub function of the XR22417 supports one configuration and supports all USB endpoints:
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Control endpoint
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Interrupt-in and interrupt-out endpoints
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Bulk-in and bulk-out endpoints
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Isochronous-in and isochronous-out endpoints
The XR22417 may be placed into a low power or suspended state by the USB host. The XR22417 hub may only be utilized
in self-powered mode. Each of the downstream ports may draw up to 500mA.
Operating the XR22417 in bus powered mode violates the USB specification, as the device reports as self-powered in
USB descriptors. A bus powered hub must provide 100mA on each downstream port but a 7-port hub cannot since it can
only draw 500mA maximum from the USB host.
USB Vendor ID
Exar’s USB vendor ID is 0x04E2.
USB Product ID
Exar’s USB hub product ID is 0x0417.
Device Reset
The XR22417 has both an automatic power-up reset and an external hardware pin reset. Strapping options selected by
tying pins to logic ‘0’ or logic ‘1’ states are sampled at either reset and the resulting hardware configuration selected by the
strapping is then set. Refer to Tables 2 and Table 3.
REV1A
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XR22417
Applications Information (Continued)
External EEPROM
An external I2C EEPROM may be used with the XR22417 to configure USB device descriptors, the number of
downstream ports, a device serial number, and downstream non-removable devices. The contents of the EEPROM are
described in Table 1. In order for contents of the EEPROM to be used by the XR22417, both the EEPROM check values at
address 0x00, 0x01 and the checksum at address 0x1F must be correct. If either field is incorrect, the EEPROM contents
will be ignored and the device will use the default descriptor values. Note that using the EEPROM requires the use of
serial numbers. By USB specification, if the hub is serialized, each individual device must be guaranteed to have a unique
serial number.
Table 1: EEPROM Contents
Address
Content
Description
0x00
0x01
0x02
0x03
0x04
0x05
0x06
0x07
0x40
EEPROM check value.
0x1A
EEPROM check value.
Vendor ID, LSB
Vendor ID, MSB
Product ID, LSB
Product ID, MSB
Device Release, LSB
Device Release, MSB
idVendor field LSB of device descriptor.
idVendor field MSB of device descriptor.
idProduct field LSB of device descriptor.
idProduct field MSB of device descriptor.
bcdDevice field LSB of device descriptor in binary coded decimal format.
bcdDevice field MSB of device descriptor in binary coded decimal format.
ASCII alpha-numeric serial number with maximum length 16 characters. First character of
serial number string in location 0x08.
0x08 to 0x17
Device Serial Number
0x18
0x19
Serial Number Length
0x00
Length of device serial number.
Reserved.
Number of downstream ports in the bNbrPorts field of the hub descriptor. EEPROM value
will take precedence over any strapping options from Table 2 and Table 3.
0x1A
0x1B
Downstream Ports
0x00
Reserved.
Device removable field of hub descriptor. Bit n = ‘0’ indicates a removable device, or bit n =
‘1’ indicates a non-removable device for port n, (n = port 1 - 7). Bit 0 is reserved. EEPROM
value will take precedence over any strapping options from Table 2 and Table 3.
0x1C
0x1D
Device Removable
0x00
Reserved.
Bit 0: port indicators support, bit 7 of wHubCharacteristics field of hub descriptor - 0: port
indicators are not supported on its downstream facing ports and PORT_ INDICATOR
request has no effect. 1: port indicators are supported on its downstream facing ports and
PORT _INDICATOR request controls the indicators.
Bit 1: identifies a compound device, bit 2 of wHubCharacteristics field of hub descriptor - 0:
hub is not part of a compound device. 1: hub is part of a compound device.
0x1E
0x1F
Device Attributes
Bit 2: maximum current requirements of the hub controller electronics, bHubContrCurrent
field of hub descriptor - 0: 200 mA. 1: 500 mA.
Bit 3 to 7, reserved, must be 0’s.
Checksum
Bitwise checksum of EEPROM values from address 0x00 to 0x1E.
REV1A
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XR22417
Applications Information (Continued)
Configurations for Reduced Downstream Ports
The number of usable downstream ports of the XR22417 may be configured using an external EEPROM. Additionally,
the number of usable downstream ports may be reduced from 7 down to a minimum of 4 by strapping options on the device,
shown in Table 2. Both the EEPROM values and the strapping options will change the bNbrPorts field of the hub descriptor
reported to the USB host. LED pins for unusable downstream ports are disabled.
Table 2: Strapping Options for Reducing Usable Downstream Ports
Usable Downstream Ports
LED7
LED6
4, 3, 2, 1
5, 4, 3, 2, 1
Logic ‘0’
Normal
Logic ‘0’
Normal
Logic ‘0’
Logic ‘0’
Normal
Normal
6, 5, 4, 3, 2, 1
7, 6, 5, 4, 3, 2, 1
Configurations for Non-Removable Devices
Non-removable devices are reported in the device removable field of the hub descriptor. They can be identified by
strapping options. LED pins for non-removable downstream ports are disabled.
Table 3: Strapping Options for Configuring Non-Removable Downstream Ports
Non-Removable Downstream Ports
LED4
LED3
LED2
None
2
Normal
Normal
Normal
Normal
Logic ‘0’
Logic ‘0’
Logic ‘0’
Logic ‘0’
Normal
Normal
Logic ‘0’
Logic ‘0’
Normal
Normal
Logic ‘0’
Logic ‘0’
Normal
Logic ‘0’
Normal
Logic ‘0’
Normal
Logic ‘0’
Normal
Logic ‘0’
3, 2
3, 2, 1
4, 3, 2, 1
5, 4, 3, 2, 1
6, 5, 4, 3, 2, 1
7, 6, 5, 4, 3, 2, 1
REV1A
10/17
XR22417
Applications Information (Continued)
Port Status Indicators
Seven port indicator (LED1 - LED7) pins, provide status of downstream devices. Ports using LED indicators may configure
status LEDs in a number of configurations in conjunction with the LED_CTL pin. Per the USB 2.0 spec, amber and green
LEDs are used to indicate port status automatically controlled by the USB hub. When the hub is suspended or not yet
configured the LEDs must be off, solid green indicates normal operation, and amber or flashing green and/or amber indicate
various error conditions as defined in the specification. The TEST#/SDA and LED1/SCL pins may also be connected to an
external EEPROM.
A2
A1
A0
TEST#/SDA
LED1/SCL
LED2
SDA
SCL
EEPROM
Green
Amber
Green
Amber
Green
Amber
LED3
Green
Amber
LED4
LED5
XR22417
Green
Amber
Green
Amber
LED6
Green
Amber
LED7
LED_CTL
470
Red
Hub active
indicator (optional)
Figure 3. Port and Hub Status Indicators
REV1A
11/17
XR22417
Applications Information (Continued)
In the following example, LED3 is tied to logic ‘0’ indicating that port 2 and 3 are connected to non-removable devices.
LED6 is also connected to logic ‘0’ indicating there are 5 usable ports, ports 1-5. LED2 and LED7 are unneeded and
left floating. Ports 1, 4 and 5 may be used for removable devices.
A2
A1
A0
TEST#/SDA
LED1/SCL
LED2
SDA
SCL
EEPROM
Green
Amber
LED3
Green
Amber
LED4
LED5
XR22417
Green
Amber
LED6
LED7
LED_CTL
470
Red
Hub active
indicator (optional)
Figure 4. Port Indicators Example
REV1A
12/17
XR22417
Applications Information (Continued)
Power Control and Overcurrent Protection
In the LQFP-64 package, the XR22417 OVCn# pins monitor overcurrent conditions for each port and individual PWRn#
pins enable power to devices connected to each downstream port. Figure 5 depicts downstream ports 1-4 using individual
power and overcurrent protection.
NOTE:
Ports 5-7 are unused in this example. If used can duplicate the monitor and control using the XRP2528.
3.3V
5V
To VBUS of Port 1
To VBUS of Port 2
ENA
OUTA
IN
OVC1#
OVC2#
OVC3#
OVC4#
OVC5#
OVC6#
OVC7#
FLGA
FLGB
ENB
XRP2528
GND
OUTB
RSETB
RSETA
To VBUS of Port 3
To VBUS of Port 4
ENA
OUTA
IN
FLGA
FLGB
ENB
XR22417
XRP2528
GND
OUTB
RSETB
PWR1#
PWR2#
PWR3#
PWR4#
PWR5#
PWR6#
PWR7#
RSETA
Figure 5. LQFP-64 Individual Power Control and Overcurrent Mode
USB Hub Drivers
All operating systems provide a native USB hub device driver for the XR22417 device to operate. No other device drivers
are necessary for the XR22417.
Regulated 3.3V Power Output
The XR22417 internal voltage regulator provides 3.3 VDC output power from 5V input, which can be utilized by
other circuitry. Refer to Electrical Characteristics on page 2 for maximum power capability.
REV1A
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XR22417
Applications Information (Continued)
External Crystal
A 12 MHz 50 PPM fundamental frequency external crystal must be connected between the XTALIN and XTALOUT pins
of the XR22417 device. The crystal should have a rated load capacitance of 16-20pF. However, note that both the load
capacitors and feedback resistance are internal to the XR22417 device as shown.
Y1
Figure 6. Typical Oscillator Connections
REV1A
14/17
XR22417
Package Description
LQFP-48
TOP VIEW
DETAIL A
SIDE VIEW
TERMINAL DIMENSION
TYPICAL RECOMMENDED LAND PATTERN
- Control dimensions are in Millimeters
- Jedec MS 026
Drawing No. : POD - 00000096
Revision: A
REV1A
15/17
XR22417
Package Description (Continued)
LQFP-64
TOP VIEW
DETAIL A
SIDE VIEW
TERMINAL DIMENSION
TYPICAL RECOMMENDED LAND PATTERN
1. Control dimensions are in Millimeters
2. Dimensions and tolerance per Jedec MS-026
Drawing No. : POD - 00000092
Revision: A
REV1A
16/17
XR22417
Ordering Information(1)
Part Number
Operating Temperature Range
Lead-Free
Yes(2)
Package
Packaging Method
XR22417CV48-F
XR22417CV48TR-F
XR22417CV64-F
XR22417CV48EVB
XR22417CV64EVB
Tray
Reel
Tray
48-pin LQFP
64-pin LQFP
0°C to 70°C
Evaluation board for LQFP-48
Evaluation board for LQFP-64
NOTE:
1. Refer to www.exar.com/XR22417 for most up-to-date Ordering Information.
2. Visit www.exar.com for additional information on Environmental Rating.
Revision History
Revision
1A
Date
Description
Aug 2016
Initial Release
www.exar.com
48760 Kato Road
Fremont, CA 94538
USA
Tel.: +1 (510) 668-7000
Fax: +1 (510) 668-7001
Email: uarttechsupport@exar.com
Exar Corporation reserves the right to make changes to the products contained in this publication in order to improve design, performance or reliability. Exar Corporation conveys
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