AD EVAL-ADUM4160EBZ Full/low speed 5 kv usb digital isolator Datasheet

Full/Low Speed 5 kV USB Digital Isolator
ADuM4160
USB 2.0 compatible
Low and full speed data rate: 1.5 Mbps and 12 Mbps
Bidirectional communication
4.5 V to 5.5 V VBUS operation
7 mA maximum upstream supply current @ 1.5 Mbps
8 mA maximum upstream supply current @ 12 Mbps
2.3 mA maximum upstream idle current
Upstream short-circuit protection
Class 3A contact ESD performance per ANSI/ESD STM5.1-2007
High temperature operation: 105°C
High common-mode transient immunity: >25 kV/ μs
16-lead SOIC wide-body package version
16-lead SOIC wide body enhanced creepage version
RoHS compliant
Safety and regulatory approvals (RI-16 package)
UL recognition: 5000 V rms for 1 minute per
UL 1577
CSA Component Acceptance Notice #5A
IEC 60601-1: 250 V rms (reinforced)
IEC 60950-1: 400 V rms (reinforced)
VDE Certificate of Conformity
DIN V VDE V 0884-10 (VDE V 0884-10):2006-12
VIORM = 846 V peak
APPLICATIONS
USB peripheral isolation
Isolated USB hub
Medical applications
GENERAL DESCRIPTION
The ADuM41601 is a USB port isolator, based on Analog Devices,
Inc., iCoupler® technology. Combining high speed CMOS and
monolithic air core transformer technology, these isolation
components provide outstanding performance characteristics
and are easily integrated with low and full speed USB-compatible
peripheral devices.
1
FUNCTIONAL BLOCK DIAGRAM
VBUS1 1
REG
REG
16 VBUS2
GND1 2
15 GND2
VDD1 3
14 VDD2
PDEN 4
13 SPD
SPU 5
12 PIN
UD– 6
11 DD–
UD+ 7
10 DD+
GND1 8
9
PU LOGIC
PD LOGIC
GND2
08171-001
FEATURES
Figure 1.
Many microcontrollers implement USB so that it presents only
the D+ and D− lines to external pins. This is desirable in many
cases because it minimizes external components and simplifies
the design; however, this presents particular challenges when
isolation is required. USB lines must automatically switch between
actively driving D+/D−, receiving data, and allowing external
resistors to set the idle state of the bus. The ADuM4160 provides
mechanisms for detecting the direction of data flow and control
over the state of the output buffers. Data direction is determined
on a packet-by-packet basis.
The ADuM4160 uses the edge detection based iCoupler technology in conjunction with internal logic to implement a
transparent, easily configured, upstream facing port isolator.
Isolating an upstream facing port provides several advantages
in simplicity, power management, and robust operation.
The isolator has propagation delay comparable to that of a
standard hub and cable. It operates with the bus voltage on
either side ranging from 4.5 V to 5.5 V, allowing connection
directly to VBUS by internally regulating the voltage to the signaling
level. The ADuM4160 provides isolated control of the pull-up
resistor to allow the peripheral to control connection timing.
The device has a low idle current; so a suspend mode is not
required. A 2.5 kV version, the ADuM3160, is also available.
Protected by U.S. Patents 5,952,849; 6,873,065; 7,075,329.
Rev. C
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
www.analog.com
Tel: 781.329.4700
Fax: 781.461.3113 ©2009-2010 Analog Devices, Inc. All rights reserved.
ADuM4160
TABLE OF CONTENTS
Features .............................................................................................. 1
ESD Caution...................................................................................7
Applications ....................................................................................... 1
Pin Configuration and Function Descriptions..............................8
General Description ......................................................................... 1
Applications Information .............................................................. 10
Functional Block Diagram .............................................................. 1
Functional Description .............................................................. 10
Revision History ............................................................................... 2
Product Usage ............................................................................. 10
Specifications..................................................................................... 3
Compatibility of Upstream Applications ................................ 10
Electrical Characteristics ............................................................. 3
Power Supply Options ............................................................... 11
Package Characteristics ............................................................... 4
Printed Circuit Board Layout (PCB) ....................................... 11
Regulatory Information ............................................................... 4
DC Correctness and Magnetic Field Immunity ..................... 11
Insulation and Safety-Related Specifications ............................ 5
Insulation Lifetime ..................................................................... 12
DIN V VDE V 0884-10 (VDE V 0884-10) Insulation
Characteristics .............................................................................. 5
Outline Dimensions ....................................................................... 14
Ordering Guide .......................................................................... 14
Recommended Operating Conditions ...................................... 6
Absolute Maximum Ratings............................................................ 7
REVISION HISTORY
10/10—Rev. B to Rev. C
Changes to Features and General Description Section ............... 1
Changes to Endnote 3 in Table 1 and Table 3 ............................... 4
Changes to Table 4 ............................................................................ 5
Changes to Table 7 and Table 8 ....................................................... 7
Updated Outline Dimensions ....................................................... 14
Changes to Ordering Guide .......................................................... 14
8/10—Rev. A to Rev. B
Change to Data Sheet Title .............................................................. 1
Changes to Features Section............................................................ 1
Changes to Applications Section .................................................... 1
Changes to General Description Section ...................................... 1
Changes to Table 3 ............................................................................ 4
9/09—Rev. 0 to Rev. A
Added USB Logo, Reformatted Page 1 .......................................... 1
7/09—Revision 0: Initial Version
Rev. C | Page 2 of 16
ADuM4160
SPECIFICATIONS
ELECTRICAL CHARACTERISTICS
4.5 V ≤ VBUS1 ≤ 5.5 V, 4.5 V ≤ VBUS2 ≤ 5.5 V; 3.1 V ≤ VDD1 ≤ 3.6 V, 3.1 V ≤ VDD2 ≤ 3.6 V; all minimum/maximum specifications apply over
the entire recommended operation range, unless otherwise noted; all typical specifications are at TA = 25°C, VDD1 = VDD2 = 3.3 V. Each
voltage is relative to its respective ground.
Table 1.
Parameter
DC SPECIFICATIONS
Total Supply Current 1
1.5 Mbps
VDD1 or VBUS1 Supply Current
VDD2 or VBUS2 Supply Current
12 Mbps
VDD1 or VBUS1 Supply Current
VDD2 or VBUS2 Supply Current
Idle Current
VDD1 or VBUS1 Idle Current
Input Currents
Single-Ended Logic High Input Threshold
Single-Ended Logic Low Input Threshold
Single-Ended Input Hysteresis
Differential Input Sensitivity
Logic High Output Voltages
Logic Low Output Voltages
VDD1 and VDD2 Supply Undervoltage Lockout
VBUS1 Supply Undervoltage Lockout
VBUS2 Supply Undervoltage Lockout
Transceiver Capacitance
Capacitance Matching
Full Speed Driver Impedance
Impedance Matching
SWITCHING SPECIFICATIONS, I/O PINS LOW SPEED
Low Speed Data Rate
Propagation Delay2
Side 1 Output Rise/Fall Time (10% to 90%) Low
Speed
Low Speed Differential Jitter, Next Transition
Low Speed Differential Jitter, Paired Transition
SWITCHING SPECIFICATIONS, I/O PINS FULL SPEED
Full Speed Data Rate
Propagation Delay2
Symbol
Typ
Max
Unit
Test Conditions
IDD1 (L)
IDD2 (L)
5
5
7
7
mA
mA
750 kHz logic signal rate CL = 450 pF
750 kHz logic signal rate CL = 450 pF
IDD1 (F)
IDD2 (F)
6
6
8
8
mA
mA
6 MHz logic signal rate CL = 50 pF
6 MHz logic signal rate CL = 50 pF
1.7
+0.1
2.3
+1
mA
µA
IDD1 (I)
IDD−, IDD+,
IUD+, IUD−,
ISPD, IPIN,
ISPU, IPDEN
VIH
VIL
VHST
VDI
VOH
VOL
VUVLO
VUVLOB1
VUVLOB2
CIN
ZOUTH
Min
−1
2.0
0.8
0.4
0.2
2.8
0
2.4
3.5
3.5
3.6
0.3
3.1
4.35
4.4
10
10
4
20
10
1.5
tPHLL, tPLHL
tRL/tFL
325
75
|tLJN|
|tLJP|
300
45
15
tPHLF, tPLHF
20
Output Rise/Fall Time (10% to 90%) Full Speed
tRF/tFF
4
Full Speed Differential Jitter, Next Transition
Full Speed Differential Jitter, Paired Transition
|tFJN|
|tFJP|
12
60
70
20
3
1
Rev. C | Page 3 of 16
V
V
V
V
V
V
V
V
V
pF
%
Ω
%
0 V ≤ VDD-, VDD+, VUD+,VUD−, VSPD, VPIN,
VSPU, VPDEN ≤ 3.0
|VXD+ − VXD−|
RL = 15 kΩ, VL = 0 V
RL = 1.5 kΩ, VL = 3.6 V
UD+, UD−, DD+, DD− to ground
Mbps CL = 50 pF
ns
CL = 50 pF, SPD = SPU = low VDD1,
VDD2 = 3.3 V
ns
CL = 450 pF SPD = SPU = low VDD1,
VDD2 = 3.3 V
ns
CL = 50 pF
ns
CL = 50 pF
Mbps CL = 50 pF
ns
CL = 50 pF SPD = SPU = high, VDD1,
VDD2 = 3.3 V
ns
CL = 50 pF SPD = SPU = high, VDD1,
VDD2 = 3.3 V
ns
CL = 50 pF
ns
CL = 50 pF
ADuM4160
Parameter
For All Operating Modes
Common-Mode Transient Immunity
At Logic High Output3
At Logic Low Output3
Symbol
Min
Typ
|CMH|
25
35
|CML|
25
35
Max
Unit
Test Conditions
kV/µs VUD+, VUD−, VDD+, VDD− = VDD1 or VDD2,
VCM = 1000 V, transient magnitude =
800 V
kV/µs VUD+, VUD−, VDD+, VDD− = 0 V, VCM =
1000 V, transient magnitude = 800 V
1
The supply current values for the device running at a fixed continuous data rate at 50% duty cycle alternating J and K states. Supply current values are specified with
USB-compliant load present.
2
Propagation delay of the low speed DD+ to UD+ or DD− to UD− in either signal direction is measured from the 50% level of the rising or falling edge, to the 50% level
of the rising or falling edge of the corresponding output signal.
3
CMH is the maximum common-mode voltage slew rate that can be sustained while maintaining VO > 0.8 VDDx. CML is the maximum common-mode voltage slew rate
that can be sustained while maintaining VO < 0.8 V. The common-mode voltage slew rates apply to both rising and falling common-mode voltage edges. The transient
magnitude is the range over which the common mode is slewed.
PACKAGE CHARACTERISTICS
Table 2.
Parameter
Resistance (Input to Output)1
Capacitance (Input to Output)1
Input Capacitance2
IC Junction-to-Ambient Thermal Resistance
1
2
Symbol
RI-O
CI-O
CI
θJA
Min
Typ
1012
2.2
4.0
45
Max
Unit
Ω
pF
pF
°C/W
Test Conditions
f = 1 MHz
Thermocouple located at
center of package underside
Device is considered a 2-terminal device; Pin 1, Pin 2, Pin 3, Pin 4, Pin 5, Pin 6, Pin 7, and Pin 8 are shorted together and Pin 9, Pin 10, Pin 11, Pin 12, Pin 13, Pin 14,
Pin 15, and Pin 16 are shorted together.
Input capacitance is from any input data pin to ground.
REGULATORY INFORMATION
The ADuM4160 is approved by the organizations listed in Table 3. Refer to Table 8 and the Insulation Lifetime section for details
regarding recommended maximum working voltages for specific cross-isolation waveforms and insulation levels.
Table 3.
UL
Recognized under 1577 component
recognition program1
Single Protection
5000 V rms Isolation Voltage
File E214100
1
2
CSA
Approved under CSA Component
Acceptance Notice #5A
Basic insulation per CSA 60950-1-03 and IEC 60950-1,
600 V rms (848 V peak) maximum working voltage
Reinforced insulation per CSA 60950-1-03 and IEC
60950-1, 380 V rms (537 V peak) maximum working
voltage, RW-16 package.
Reinforced insulation per CSA 60950-1-03 and IEC
60950-1, 400 V rms (565 V peak) maximum working
voltage, RI-16 package.
Reinforced insulation per IEC 60601-1 125 V rms (176 V
peak) maximum working voltage, RW-16 package.
Reinforced insulation per IEC 60601-1 250 V rms (353 V
peak) maximum working voltage, RI-16 package.
File 205078
VDE
Certified according to DIN V VDE V
0884-10 (VDE V 0884-10):2006-122
Reinforced insulation, 846 V peak
File 2471900-4880-0001
In accordance with UL 1577, each ADuM4160 is proof tested by applying an insulation test voltage ≥6000 V rms for 1 sec (current leakage detection limit = 10 µA).
In accordance with DIN V VDE V 0884-10, each ADuM4160 is proof tested by applying an insulation test voltage ≥1050 V peak for 1 sec (partial discharge detection
limit = 5 pC). The * marking branded on the component designates DIN V VDE V 0884-10 approval.
Rev. C | Page 4 of 16
ADuM4160
INSULATION AND SAFETY-RELATED SPECIFICATIONS
Table 4.
Parameter
Rated Dielectric Insulation Voltage
Minimum External Air Gap (Clearance)
Symbol Value
5000
L(I01)
8.0 min
Minimum External Tracking (Creepage) RW-16 Package L(I02)
Minimum External Tracking (Creepage) RI-16 Package
L(I02)
Minimum Internal Gap (Internal Clearance)
Tracking Resistance (Comparative Tracking Index)
Isolation Group
CTI
Unit Conditions
V rms 1 minute duration
mm
Measured from input terminals to output terminals,
shortest distance through air
7.7 min
mm
Measured from input terminals to output terminals,
shortest distance path along body
8.5 min
mm
Measured from input terminals to output terminals,
shortest distance path along body
0.017 min mm
Insulation distance through insulation
>175
V
DIN IEC 112/VDE 0303 Part 1
IIIa
Material Group (DIN VDE 0110, 1/89, Table 1)
DIN V VDE V 0884-10 (VDE V 0884-10) INSULATION CHARACTERISTICS
These isolators are suitable for reinforced electrical isolation only within the safety limit data. Maintenance of the safety data is ensured by
protective circuits. The * marking on packages denotes DIN V VDE V 0884-10 approval.
Table 5.
Description
Installation Classification per DIN VDE 0110
For Rated Mains Voltage ≤ 150 V rms
For Rated Mains Voltage ≤ 300 V rms
For Rated Mains Voltage ≤ 400 V rms
Climatic Classification
Pollution Degree per DIN VDE 0110, Table 1
Maximum Working Insulation Voltage
Input-to-Output Test Voltage, Method b1
Conditions
VIORM × 1.875 = VPR, 100% production test, tm = 1 sec,
partial discharge < 5 pC
VIORM × 1.6 = VPR, tm = 60 sec, partial discharge < 5 pC
Input-to-Output Test Voltage, Method a
After Environmental Tests Subgroup 1
After Input and/or Safety Test Subgroup 2
and Subgroup 3
Highest Allowable Overvoltage
Safety-Limiting Values
Symbol
Characteristic
Unit
VIORM
VPR
I to IV
I to III
I to II
40/105/21
2
846
1590
V peak
V peak
1375
1018
V peak
V peak
VTR
6000
V peak
TS
IS1
RS
150
550
>109
°C
mA
Ω
VPR
VIORM × 1.2 = VPR, tm = 60 sec, partial discharge < 5 pC
Transient overvoltage, tTR = 10 seconds
Maximum value allowed in the event of a failure
(see Figure 2)
Case Temperature
Side 1+ Side 2 Current
Insulation Resistance at TS
VIO = 500 V
500
400
300
200
100
0
0
50
100
150
AMBIENT TEMPERATURE (°C)
200
08171-002
SAFE OPERATING VDD1 CURRENT (mA)
600
Figure 2. Thermal Derating Curve, Dependence of Safety-Limiting Values with Case Temperature per DIN V VDE V 0884-10
Rev. C | Page 5 of 16
ADuM4160
RECOMMENDED OPERATING CONDITIONS
Table 6.
Parameter
Operating Temperature
Supply Voltages1
Input Signal Rise and Fall Times
1
Symbol
TA
VBUS1, VBUS2
Min
−40
3.1
Max
+105
5.5
1.0
Unit
°C
V
ms
All voltages are relative to their respective ground. See the DC Correctness and Magnetic Field Immunity section for information on immunity to external magnetic
fields.
Rev. C | Page 6 of 16
ADuM4160
ABSOLUTE MAXIMUM RATINGS
Ambient temperature = 25°C, unless otherwise noted.
Stresses above those listed under Absolute Maximum Ratings
may cause permanent damage to the device. This is a stress
rating only; functional operation of the device at these or any
other conditions above those indicated in the operational
section of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect
device reliability.
Table 7.
Parameter
Storage Temperature (TST)
Ambient Operating Temperature (TA)
Supply Voltages (VBUS1, VBUS2, VDD1,
VDD2) 1
Upsream Input Voltage
(VUD+,VUD−, VSPU)1, 2
Downstream Input Voltage
(VDD+, VDD−, VSPD, VPIN)1, 2
Average Output Current per Pin 3
Side 1 (IO1)
Side 2 (IO2)
Common-Mode Transients 4
Rating
−65°C to +150°C
−40°C to +105°C
−0.5 V to +6.5 V
−0.5 V to VDD1 + 0.5 V
Table 8. Maximum Continuous Working Voltage1
−0.5 V to VDD2 + 0.5 V
−10 mA to +10 mA
−10 mA to +10 mA
−100 kV/µs to +100 kV/µs
Parameter
AC Voltage, Bipolar
Waveform
AC Voltage, Unipolar
Waveform
Basic Insulation
Max
565
Unit
V peak
Constraint
50-year minimum
lifetime
848
V peak
846
V peak
Maximum approved
working voltage per
IEC 60950-1
Maximum approved
working voltage per
VDE 0884-10
848
V peak
846
V peak
1
All voltages are relative to their respective ground.
VDDI, VBUS1, and VDD2, VBUS2 refer to the supply voltages on the upstream and
downstream sides of the coupler, respectively.
3
See Figure 2 for maximum rated current values for various temperatures.
4
Refers to common-mode transients across the insulation barrier. Commonmode transients exceeding the absolute maximum ratings may cause latchup or permanent damage.
Reinforced Insulation
2
DC Voltage
Basic Insulation
Reinforced Insulation
1
Maximum approved
working voltage per
IEC60950-1
Maximum approved
working voltage per
VDE 0884-10
Refers to continuous voltage magnitude imposed across the isolation
barrier. See the Insulation Lifetime section for more details.
ESD CAUTION
Rev. C | Page 7 of 16
ADuM4160
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
VBUS1 1
16
VBUS2
GND1* 2
15
GND2*
14
VDD2
VDD1 3
PDEN 4
SPU 5
ADuM4160
13 SPD
TOP VIEW
(Not to Scale) 12 PIN
UD– 6
11
DD–
UD+ 7
10
DD+
GND1* 8
9
GND2*
*PIN 2 AND PIN 8 ARE INTERNALLY CONNECTED, AND CONNECTING
BOTH TO GND1 IS RECOMMENDED. PIN 9 AND PIN 15 ARE INTERNALLY
CONNECTED, AND CONNECTING BOTH TO GND2 IS RECOMMENDED.
08171-003
NC = NO CONNECT
Figure 3. Pin Configuration
Table 9. Pin Function Descriptions
Pin No.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Mnemonic Direction Description
VBUS1
Power
Input Power Supply for Side 1. Where the isolator is powered by the USB bus voltage, 4.5 V to 5.5 V,
connect VBUS1 to the USB power bus. Where the isolator is powered from a 3.3 V power supply, connect
VBUS1 to VDD1 and to the external 3.3 V power supply. Bypass to GND1 is required.
GND1
Return
Ground 1. Ground reference for Isolator Side 1.
VDD1
Power
Power Supply for Side 1. Where the isolator is powered by the USB bus voltage, 4.5 V to 5.5 V, the VDDI pin
should be used for a bypass capacitor to GND1. Signal lines that may require pull up, such as PDEN and
SPU, should be tied to this pin. Where the isolator is powered from a 3.3 V power supply, connect VBUS1 to
VDD1 and to the external 3.3 V power supply. Bypass to GND1 is required.
PDEN
Input
Pull-Down Enable. This pin is read when exiting reset. For standard operation, connect this pin to VDD1.
When connected to GND1 while exiting from reset, the downstream pull-down resistors are
disconnected, allowing buffer impedance measurements.
SPU
Input
Speed Select Upstream Buffer. Active high logic input. Selects full speed slew rate, timing, and logic
conventions when SPU is high, and low speed slew rate, timing, and logic conventions when SPU is tied
low. This input must be set high via connection to VDD1 or set low via connection to GND1 and must
match Pin 13.
UD−
I/O
Upstream D−.
UD+
I/O
Upstream D+.
GND1
Return
Ground 1. Ground reference for Isolator Side 1.
GND2
Return
Ground 2. Ground reference for Isolator Side 2.
DD+
I/O
Downstream D+.
DD−
I/O
Downstream D−.
PIN
Input
Upstream Pull-Up Enable. PIN controls the power connection to the pull-up for the upstream port. It can
be tied to VDD2 for operation on power-up, or tied to an external control signal for applications requiring
delayed enumeration.
SPD
Input
Speed Select Downstream Buffer. Active high logic input. Selects full speed slew rate, timing, and logic
conventions when SPD is high, and low speed slew rate, timing, and logic conventions when SPD is tied
low. This input must be set high via connection to VDD2 or low via connection to GND2, and must match
Pin 5.
VDD2
Power
Power Supply for Side 2. Where the isolator is powered by the USB bus voltage, 4.5 V to 5.5 V, the VDD2
pin should be used for a bypass capacitor to GND2. Signal lines that may require pull-up, such as SPD,
can be tied to this pin. Where the isolator is powered from a 3.3 V power supply, connect VBUS2 to VDD2
and to the external 3.3 V power supply. Bypass to GND2 is required.
GND2
Return
Ground 2. Ground reference for Isolator Side 2.
VBUS2
Power
Input Power Supply for Side 2. Where the isolator is powered by the USB bus voltage, 4.5 V to 5.5 V,
connect VBUS2 to the USB power bus. Where the isolator is powered from a 3.3 V power supply, connect
VBUS2 to VDD2 and to the external 3.3 V power supply. Bypass to GND2 is required.
Rev. C | Page 8 of 16
ADuM4160
Table 10. Truth Table, Control Signals, and Power (Positive Logic)1
VSPU
Input
H
VBUS1, VDD1
State
Powered
VUD+,
VUD−
State
Active
VSPD
Input
H
VBUS2, VDD2
State
Powered
VDD+,
VDD−
State
Active
VPIN
Input
H
L
Powered
Active
L
Powered
Active
H
L
Powered
Active
H
Powered
Active
H
H
Powered
Active
L
Powered
Active
H
X
Powered
Z
X
Powered
Z
L
X
Unpowered
X
X
Powered
Z
X
X
Powered
Z
X
Unpowered
X
X
1
Notes
Input and output logic set for full speed logic convention
and timing.
Input and output logic set for low speed logic convention
and timing.
Not allowed: VSPU and VSPD must be set to the same value.
USB host detects communications error.
Not allowed: VSPU and VSPD must be set to the same value.
USB host detects communications error.
Upstream Side 1 presents a disconnected state to the USB
cable.
When power is not present on VDD1, the downstream data
output drivers revert to high-Z within 32 bit times. The
downstream side initializes in high-Z state.
When power is not present on the VDD2, the upstream side
disconnects the pull-up and disables the upstream drivers
within 32 bit times.
H represents logic high input or output, L represents logic low input or output, X represents the don’t care logic input or output, and Z represents the high impedance
output state.
Rev. C | Page 9 of 16
ADuM4160
APPLICATIONS INFORMATION
FUNCTIONAL DESCRIPTION
1.
The iCoupler technology is based on edge detection, and,
therefore, lends itself well to the USB application. The flow of
data through the device is accomplished by monitoring the
inputs for activity and setting the direction for data transfer
based on a transition from the idle (J) state. When data
direction is established, data is transferred until either an endof-packet (EOP) or a sufficiently long idle state is encountered.
At this point, the coupler disables its output buffers and
monitors its inputs for the next activity
During the data transfers, the input side of the coupler holds its
output buffers disabled. The output side enables its output buffers
and disables edge detection from the input buffers. This allows
the data to flow in one direction without wrapping back through
the coupler making the iCoupler latch. Logic is included to
eliminate any artifacts due to different input thresholds of the
differential and single-ended buffers. The input state is transferred
across the isolation barrier as one of three valid states, J, K, or
SE0. The signal is reconstructed at the output side with a fixed
time delay from the input side differential input.
The iCoupler does not have a special suspend mode, nor does it
need one because its power supply current is below the suspend
current limit of 2.5 mA when the USB bus is idle.
The ADuM4160 is designed to interface with an upstream
facing low/full speed USB port by isolating the D+/D− lines.
An upstream facing port supports only one speed of operation,
thus, the speed related parameters, J/K logic levels, and D+/D−
slew rate are set to match the speed of the upstream facing
peripheral port (see Table 10).
A control line on the downstream side of the ADuM4160 activates
a pull-up resistor integrated into the upstream side. This allows
the downstream port to control when the upstream port attaches
to the USB bus. The pin can be tied to the peripheral pull-up, a
control line, or the VDD2 pin, depending on when the initial bus
connect is to be performed.
PRODUCT USAGE
The ADuM4160 is designed to be integrated into a USB
peripheral with an upstream facing USB port as shown in
Figure 4. The key design points are:
2.
3.
4.
5.
6.
PERIPHERAL
VDD2
DD+
USB
HOST
DD–
GND1
3.3V
VBUS2
VBUS1
DD+
ADuM4160
DD–
PIN
MICROCONTROLLER
POWER
SUPPLY
08171-004
USB isolation in the D+/D− lines is challenging for several
reasons. First, access to the output enable signals is normally
required to control a transceiver. Some level of intelligence must
be built into the isolator to interpret the data stream and
determine when to enable and disable its upstream and downstream output buffers. Second, the signal must be faithfully
reconstructed on the output side of the coupler while retaining
precise timing and not passing transient states such as invalid
SE0 and SE1 states. In addition, the part must meet the low
power requirements of the suspend mode.
The USB host provides power for the upstream side of the
ADuM4160 through the cable.
The peripheral supply provides power to the downstream
side of the ADuM4160
The DD+/DD− lines of the isolator interface with the
peripheral controller, and the UD+/UD− lines of the
isolator connect to the cable or host.
Peripheral devices have a fixed data rate that is set at design
time. The ADuM4160 has configuration pins, SPU and
SPD, that determine the buffer speed and logic convention
for each side. These must be set identically and match the
desired peripheral speed.
USB enumeration begins when either the UD+ or UD−
line is pulled high at the peripheral end of the USB cable,
which is the upstream side of the ADuM4160. Control of
the timing of this event is provided by the PIN input on the
downstream side of the coupler.
Pull-up and pull-down resistors are implemented inside
the coupler. Only external series resistors and bypass
capacitors are required for operation.
Figure 4. Typical Application
Other than the delayed application of pull-up resistors, the
ADuM4160 is transparent to USB traffic, and no modifications
to the peripheral design are required to provide isolation. The
isolator adds propagation delay to the signals comparable to a
hub and cable. Isolated peripherals must be treated as if there
were a built-in hub when determining the maximum number of
hubs in a data chain.
Hubs can be isolated like any other peripheral. Isolated hubs
can be created by placing an ADuM4160 on the upstream port
of a hub chip. This configuration can be made compliant if
counted as two hub delays. The hub chip allows the ADuM4160
to operate at full speed yet maintains compatibility with low
speed devices.
COMPATIBILITY OF UPSTREAM APPLICATIONS
The ADuM4160 is designed specifically for isolating a USB
peripheral. However, the chip does have two USB interfaces that
meet the electrical requirements for driving USB cables. This
opens the possibility of implementing isolation in downstream
USB ports such as isolated cables, which have generic connections
to both upstream and downstream devices, as well as isolating
host ports.
Rev. C | Page 10 of 16
ADuM4160
The practical result of using the ADuM4160 in a host port is
that the port works at a single speed. This behavior is acceptable
in embedded host applications; however, this type of interface is
not fully compliant as a general-purpose USB port.
Isolated cable applications have a similar issue. The cable operates
at the preset speed only; therefore, treat cable assemblies as
custom applications, not general-purpose isolated cables.
POWER SUPPLY OPTIONS
In most USB transceivers, 3.3 V is derived from the 5 V USB
bus through an LDO regulator. The ADuM4160 includes internal
LDO regulators on both the upstream and downstream sides.
The output of the LDO is available on the VDD1 and VDD2 pins.
In some cases, especially on the peripheral side of the isolation,
there may not be a 5 V power supply available. The ADuM4160
has the ability to bypass the regulator and run on a 3.3 V supply
directly.
Two power pins are present on each side, VBUSx and VDDx. If 5 V
is supplied to VBUSx, an internal regulator creates 3.3 V to power
the xD+ and xD− drivers. VDDx provides external access to the
3.3 V supply to allow external bypass as well as bias for external
pull-ups. If only 3.3 V is available, it can be supplied to both
VBUSx and VDDx. This disables the regulator and powers the
coupler directly from the 3.3 V supply.
Figure 5 shows how to configure a typical application when the
upstream side of the coupler receives power directly from the
USB bus and the downstream side is receiving 3.3 V from the
peripheral power supply. The downstream side can run from a
5V VBUS2 power supply as well. It can be connected in the same
manner as VBUS1 as shown in Figure 5, if needed.
PRINTED CIRCUIT BOARD LAYOUT (PCB)
The ADuM4160 digital isolator requires no external interface
circuitry for the logic interfaces. For full speed operation, the
D+ and D− line on each side of the device requires a 24 Ω ± 1%
series termination resistor. These resistors are not required for
low speed applications. Power supply bypassing is required at
the input and output supply pins (Figure 5). Install bypass
capacitors between VBUSx and VDDx on each side of the chip. The
capacitor value should have a value of 0.1 µF and be of a low
ESR type. The total lead length between both ends of the
capacitor and the power supply pin should not exceed 10 mm.
Bypassing between Pin 2 and Pin 8 and between Pin 9 and
Pin 15 should also be considered, unless the ground pair on
each package side is connected close to the package.
VBUS2 = 3.3V INPUT
VDD2 = 3.3V INPUT
VBUS1 = 5.0V INPUT
VDD1 = 3.3V OUTPUT
VBUS1
GND1
VDD1
PDEN
SPU
UD–
UD+
GND1
ADuM4160
VBUS2
GND2
VDD2
SPD
PIN
DD–
DD+
GND2
08171-005
In a fully compliant application, a downstream facing port must
be able to detect whether a peripheral is low speed or full speed
based on the application of the upstream pull-up. The buffers
and logic conventions must adjust to match the requested speed.
Because the ADuM4160 sets its speed by hard wiring pins, the
part cannot adjust to different peripherals on the fly.
Figure 5. Recommended Printed Circuit Board Layout
In applications involving high common-mode transients, it is
important to minimize board coupling across the isolation
barrier. Furthermore, design the board layout such that any
coupling that does occur equally affects all pins on a given
component side. Failure to ensure this can cause voltage
differentials between pins exceeding the absolute maximum
ratings of the device, thereby leading to latch-up or permanent
damage.
DC CORRECTNESS AND MAGNETIC FIELD
IMMUNITY
Positive and negative logic transitions at the isolator input
cause narrow (~1 ns) pulses to be sent to the decoder via the
transformer. The decoder is bistable and is, therefore, either set
or reset by the pulses, indicating input logic transitions. In the
absence of logic transitions at the input for more than about
12 USB bit times, a periodic set of refresh pulses indicative of
the correct input state are sent to ensure dc correctness at the
output. If the decoder receives no internal pulses for more than
about 36 USB bit times, the input side is assumed to be unpowered
or nonfunctional, in which case the isolator output is forced to a
default state (see Table 10) by the watchdog timer circuit.
The limitation on the magnetic field immunity of the ADuM4160
is set by the condition in which induced voltage in the receiving
Rev. C | Page 11 of 16
ADuM4160
V = (−dβ/dt)∑∏rn2; n = 1, 2, … , N
where:
β is magnetic flux density (gauss).
N is the number of turns in the receiving coil.
rn is the radius of the nth turn in the receiving coil (cm).
DISTANCE = 100mm
1
DISTANCE = 5mm
0.1
1k
10k
100k
1M
10M
MAGNETIC FIELD FREQUENCY (Hz)
100
MAXIMUM ALLOWABLE MAGNETIC FLUX
DENSITY (kguass)
10
0.01
Given the geometry of the receiving coil in the ADuM4160 and
an imposed requirement that the induced voltage is, at most,
50% of the 0.5 V margin at the decoder, a maximum allowable
magnetic field is calculated, as shown in Figure 6.
100M
Figure 7. Maximum Allowable Current
for Various Current-to-ADuM4160 Spacings
As shown, the ADuM4160 is extremely immune and can be
affected only by extremely large currents operated at high
frequency very close to the component. For the 1 MHz example
noted, a 0.5 kA current would need to be placed 5 mm away
from the ADuM4160 to affect the operation of the component.
Note that at combinations of strong magnetic field and high
frequency, any loops formed by printed circuit board traces can
induce error voltages sufficiently large enough to trigger the
thresholds of succeeding circuitry. Take care in the layout of
such traces to avoid this possibility.
10
1
INSULATION LIFETIME
0.1
10k
100k
1M
10M
MAGNETIC FIELD FREQUENCY (Hz)
100M
08171-006
0.01
0.001
1k
DISTANCE = 1m
100
08171-007
The pulses at the transformer output have an amplitude greater
than 1.0 V. The decoder has a sensing threshold of about 0.5 V, thus
establishing a 0.5 V margin in which induced voltages are tolerated.
The voltage induced across the receiving coil is given by
1000
MAXIMUM ALLOWABLE CURRENT (kA)
coil of the transformer is sufficiently large to either falsely set or
reset the decoder. The following analysis defines the conditions
under which this may occur. The 3 V operating condition of the
ADuM4160 is examined because it represents the most susceptible
mode of operation.
Figure 6. Maximum Allowable External Magnetic Flux Density
For example, at a magnetic field frequency of 1 MHz, the
maximum allowable magnetic field of 0.2 kgauss induces a
voltage of 0.25 V at the receiving coil. This is about 50% of the
sensing threshold and does not cause a faulty output transition.
Similarly, if such an event occurs during a transmitted pulse
(and is of the worst-case polarity), it reduces the received pulse
from >1.0 V to 0.75 V—still well above the 0.5 V sensing
threshold of the decoder.
The preceding magnetic flux density values correspond to specific
current magnitudes at given distances from the ADuM4160 transformers. Figure 7 expresses these allowable current magnitudes
as a function of frequency for selected distances.
All insulation structures eventually break down when subjected
to voltage stress over a sufficiently long period. The rate of
insulation degradation is dependent on the characteristics of the
voltage waveform applied across the insulation. In addition to
the testing performed by the regulatory agencies, Analog
Devices carries out an extensive set of evaluations to determine
the lifetime of the insulation structure within the ADuM4160.
Analog Devices performs accelerated life testing using voltage
levels higher than the rated continuous working voltage. Acceleration factors for several operating conditions are determined.
These factors allow calculation of the time to failure at the actual
working voltage. The values shown in Table 8 summarize the
peak voltage for 50 years of service life for a bipolar ac operating
condition, and the maximum CSA/VDE approved working voltages. In many cases, the approved working voltage is higher
than 50-year service life voltage. Operation at these high working
voltages can lead to shortened insulation life in some cases.
The insulation lifetime of the ADuM4160 depends on the voltage
waveform type imposed across the isolation barrier. The iCoupler
Rev. C | Page 12 of 16
ADuM4160
In the case of unipolar ac or dc voltage, the stress on the insulation is significantly lower. This allows operation at higher working
voltages and still achieves a 50-year service life. The working
voltages listed in Table 8 can be applied while maintaining the
50-year minimum lifetime, provided that the voltage conforms to
either the unipolar ac or dc voltage cases. Treat any cross
insulation voltage waveform that does not conform to Figure 9 or
Figure 10 as a bipolar ac waveform and limit its peak voltage to the
50-year lifetime voltage value listed in Table 8.
Note that the voltage presented in Figure 9 is shown as sinusoidal for illustration purposes only. It is meant to represent any
voltage waveform varying between 0 V and some limiting value.
The limiting value can be positive or negative, but the voltage
cannot cross 0 V.
Rev. C | Page 13 of 16
08171-008
0V
Figure 8. Bipolar AC Waveform
RATED PEAK VOLTAGE
08171-009
Bipolar ac voltage is the most stringent environment. The goal
of a 50-year operating lifetime under the ac bipolar condition
determines the Analog Devices recommended maximum
working voltage.
RATED PEAK VOLTAGE
0V
Figure 9. Unipolar AC Waveform
RATED PEAK VOLTAGE
08171-010
insulation structure degrades at different rates depending on
whether the waveform is bipolar ac, unipolar ac, or dc. Figure 8,
Figure 9, and Figure 10 illustrate these different isolation voltage
waveforms.
0V
Figure 10. DC Waveform
ADuM4160
OUTLINE DIMENSIONS
10.50 (0.4134)
10.10 (0.3976)
9
16
7.60 (0.2992)
7.40 (0.2913)
1
10.65 (0.4193)
10.00 (0.3937)
8
1.27 (0.0500)
BSC
0.30 (0.0118)
0.10 (0.0039)
COPLANARITY
0.10
0.75 (0.0295)
0.25 (0.0098)
2.65 (0.1043)
2.35 (0.0925)
8°
0°
SEATING
PLANE
0.51 (0.0201)
0.31 (0.0122)
45°
1.27 (0.0500)
0.40 (0.0157)
0.33 (0.0130)
0.20 (0.0079)
032707-B
COMPLIANT TO JEDEC STANDARDS MS-013- AA
CONTROLLING DIMENSIONS ARE IN MILLIMETERS; INCH DIMENSIONS
(IN PARENTHESES) ARE ROUNDED-OFF MILLIMETER EQUIVALENTS FOR
REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN.
Figure 11. 16-Lead Standard Small Outline Package [SOIC_W]
Wide Body (RW-16)
Dimension shown in millimeters and (inches)
13.00 (0.5118)
12.60 (0.4961)
9
16
7.60 (0.2992)
7.40 (0.2913)
0.30 (0.0118)
0.10 (0.0039)
COPLANARITY
0.10
10.65 (0.4193)
10.00 (0.3937)
8
2.65 (0.1043)
2.35 (0.0925)
1.27
(0.0500)
BSC
0.51 (0.0201)
0.31 (0.0122)
0.75 (0.0295)
45°
0.25 (0.0098)
8°
0°
SEATING
PLANE
0.33 (0.0130)
0.20 (0.0079)
1.27 (0.0500)
0.40 (0.0157)
COMPLIANT TO JEDEC STANDARDS MS-013-AC
CONTROLLING DIMENSIONS ARE IN MILLIMETERS; INCH DIMENSIONS
(IN PARENTHESES) ARE ROUNDED-OFF MILLIMETER EQUIVALENTS FOR
REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN.
10-12-2010-A
1
Figure 12. 16-Lead Standard Small Outline Package, with Increased Creepage [SOIC_IC]
Wide Body (RI-16)
Dimension shown in millimeters and (inches)
ORDERING GUIDE
Model1, 2
ADuM4160BRWZ
ADuM4160BRWZ-RL
ADuM4160BRIZ
ADuM4160BRIZ-RL
EVAL-ADUM4160EBZ
1
2
Number
of Inputs,
VDD1 Side
2
2
2
2
Number
of Inputs,
VDD2 Side
2
2
2
2
Maximum
Data Rate
(Mbps)
12
12
12
12
Maximum
Propagation
Delay, 5 V (ns)
70
70
70
70
Maximum
Jitter (ns)
3
3
3
3
Z = RoHS Compliant Part.
For all devices listed, specifications represent full speed buffer configuration.
Rev. C | Page 14 of 16
Temperature Range
−40°C to +105°C
−40°C to +105°C
−40°C to +105°C
−40°C to +105°C
Package Description
16-Lead SOIC_W
16-Lead SOIC_W
16-Lead SOIC_IC
16-Lead SOIC_IC
Evaluation Board
Package
Option
RW-16
RW-16
RI-16
RI-16
ADuM4160
NOTES
Rev. C | Page 15 of 16
ADuM4160
NOTES
©2009-2010 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D08171-0-10/10(C)
Rev. C | Page 16 of 16
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