SILABS SI8435

Si8430/31/35
T R I P L E - C H A N N E L D I G I TA L I S O L A T O R
Features
Pin Assignments
High-speed operation:
DC – 150 Mbps
Low propagation delay:
<10 ns
Wide Operating Supply Voltage:
2.375-5.5V
Low power: I1 + I2 <
12 mA/channel at 100 Mbps
Precise timing:
2 ns pulse width distortion
1 ns channel-channel matching
2 ns pulse width skew
2500 VRMS isolation
Transient Immunity: >25 kV/µs
Tri-state outputs with ENABLE
control
DC correct
No start-up initialization required
<10 µs Startup Time
High temperature operation:
125 °C at 100 Mbps
100 °C at 150 Mbps
Wide body SOIC-16 package
Wide Body SOIC
VDD1
GND1
A1
A2
A3
NC
EN1/NC
GND1
16
15
14
13
12
11
10
9
1
2
3
4
5
6
7
8
VDD2
GND2
B1
B2
B3
NC
EN2/NC
GND2
Top View
Applications
Isolated switch mode supplies
Isolated ADC, DAC
Motor control
Power factor correction systems
Safety Regulatory Approvals
UL recognition:2500 VRMS for 1
Minute per UL1577
CSA component acceptance
notice
VDE certification conformity
IEC 60747-5-2
(VDE0884 Part 2)
Description
Silicon Lab's family of digital isolators are CMOS devices that employ
an RF coupler to transmit digital information across an isolation
barrier. Very high speed operation at low power levels is achieved.
These parts are available in a 16-pin wide body SOIC package. Three
speed grade options (1, 10, 150 Mbps) are available and achieve
typical propagation delay of less than 10 ns.
Block Diagram
Si8430/35
Rev. 0.3 8/07
Si8431
A1
B1
A1
B1
A2
B2
A2
B2
A3
B3
A3
B3
NC
EN2/NC
EN1
EN2
Copyright © 2007 by Silicon Laboratories
Si8430/31/35
Si8430/31/35
2
Rev. 0.3
Si8430/31/35
TA B L E O F C O N T E N TS
Section
Page
1. Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
2. Typical Performance Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
3. Application Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
3.1. Theory of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
3.2. Eye Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
4. Layout Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
4.1. Supply Bypass . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
4.2. Input and Output Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
4.3. Enable (EN1, EN2) Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
4.4. RF Radiated Emissions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
4.5. RF Immunity and Common Mode Transient Immunity . . . . . . . . . . . . . . . . . . . . . . . 24
5. Pin Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
6. Ordering Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
7. Package Outline: Wide Body SOIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
Document Change List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
Contact Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
Rev. 0.3
3
Si8430/31/35
1. Electrical Specifications
Table 1. Electrical Characteristics
(VDD1 = 5 V, VDD2 = 5 V, TA = –40 to 125 ºC)
Parameter
Symbol
Test Condition
Min
Typ
Max
Unit
High Level Input Voltage
VIH
2.0
—
—
V
Low Level Input Voltage
VIL
—
—
0.8
V
High Level Output Voltage
VOH
loh = –4 mA
VDD1,VDD2 – 0.4
4.8
—
V
Low Level Output Voltage
VOL
lol = 4 mA
—
0.2
0.4
V
—
—
±10
µA
Input Leakage Current
IL
Enable Input High Current
IENH
VENx = VIH
—
4
—
µA
Enable Input Low Current
IENL
VENx = VIL
—
20
—
µA
DC Supply Current (All inputs 0 V or at Supply)
Si8430/35-A,-B,-C, VDD1
All inputs 0 DC
—
7
10
mA
Si8430/35-A,-B,-C, VDD2
All inputs 0 DC
—
6
9
mA
Si8430/35-A,-B,-C, VDD1
All inputs 1 DC
—
14
18
mA
Si8430/35-A,-B,-C, VDD2
All inputs 1 DC
—
6
9
mA
Si8431-A,-B,-C, VDD1
All inputs 0 DC
—
8
12
mA
Si8431-A,-B,-C, VDD2
All inputs 0 DC
—
10
15
mA
Si8431-A,-B,-C, VDD1
All inputs 1 DC
—
13
19
mA
Si8431-A,-B,-C, VDD2
All inputs 1 DC
—
12
17
mA
10 Mbps Supply Current (All inputs = 5 MHz square wave, CI = 15 pF on all outputs)
Si8430/35-B,-C, VDD1
—
11
15
mA
Si8430/35-B,-C, VDD2
—
13
17
mA
Si8431-B,-C, VDD1
—
12
16
mA
Si8431-B,-C, VDD2
—
13
17
mA
100 Mbps Supply Current (All inputs = 50 MHz square wave, CI = 15 pF on all outputs)
Si8430-C, VDD1
—
11
15
mA
Si8430-C, VDD2
—
23
28
mA
Si8431-C, VDD1
—
13
18
mA
Si8431-C, VDD2
—
21
26
mA
4
Rev. 0.3
Si8430/31/35
Table 1. Electrical Characteristics (Continued)
(VDD1 = 5 V, VDD2 = 5 V, TA = –40 to 125 ºC)
Parameter
Symbol
Test Condition
Min
Typ
Max
Unit
Maximum Data Rate
0
—
1
Mbps
Minimum Pulse Width
—
—
1000
ns
Timing Characteristics
Si843x-A
Propagation Delay
tPHL, tPLH
See Figure 2
—
—
75
ns
PWD
See Figure 2
—
—
30
ns
tPSK(P-P)
—
—
50
ns
tPSK
—
—
40
ns
Maximum Data Rate
0
—
10
Mbps
Minimum Pulse Width
—
—
100
ns
Pulse Width Distortion
|tPLH - tPHL|
Propagation Delay Skew1
Channel-Channel Skew
Si843x-B
Propagation Delay
tPHL, tPLH
See Figure 2
—
—
35
ns
PWD
See Figure 2
—
—
7.5
ns
tPSK(P-P)
—
—
25
ns
tPSK
—
—
5
ns
Maximum Data Rate
0
—
150
Mbps
Minimum Pulse Width
—
—
6.6
ns
Pulse Width Distortion
|tPLH - tPHL|
Propagation Delay Skew1
Channel-Channel Skew
Si843x-C
Propagation Delay
Pulse Width Distortion
|tPLH - tPHL|
Propagation Delay Skew1
Channel-Channel Skew
tPHL, tPLH
See Figure 2
4
6.5
9.5
ns
PWD
See Figure 2
—
—
3
ns
tPSK(P-P)
—
—
5.5
ns
tPSK
—
—
3
ns
Rev. 0.3
5
Si8430/31/35
Table 1. Electrical Characteristics (Continued)
(VDD1 = 5 V, VDD2 = 5 V, TA = –40 to 125 ºC)
Parameter
Symbol
Test Condition
Min
Typ
Max
Unit
Output Rise Time
tr
CL = 15 pF
See Figure 2
—
2
—
ns
Output Fall Time
tf
CL = 15 pF
See Figure 2
—
2
—
ns
CTMI
VI = VDD or 0 V
25
30
—
kV/µs
Enable to Data Valid
ten1
See Figure 1
—
5
—
ns
Enable to Data Tri-State
ten2
See Figure 1
—
5
—
ns
Time2
tSU
—
3
—
µs
For All Models
Common Mode Transient
Immunity
Start-up
Notes:
1. tPSK(P-P) is the magnitude of the difference in propagation delay times measured between different units operating at the
same supply voltages, load, and ambient temperature.
2. Start-up time is the time period from the application of power to valid data at the output.
ENABLE
OUTPUTS
ten1
ten2
Figure 1. ENABLE Timing Diagram
50%
Typical
Input
tPLH
tPHL
90%
90%
10%
10%
50%
Typical
Output
tr
tf
Figure 2. Propagation Delay Timing
6
Rev. 0.3
Si8430/31/35
Table 2. Electrical Characteristics
(VDD1 = 3.3 V, VDD2 = 3.3 V, TA = –40 to 125 ºC)
Parameter
Symbol
Test Condition
Min
Typ
Max
Unit
High Level Input Voltage
VIH
2.0
—
—
V
Low Level Input Voltage
VIL
—
—
0.8
V
High Level Output Voltage
VOH
loh = –4 mA
VDD1,VDD2 – 0.4
3.1
—
V
Low Level Output Voltage
VOL
lol = 4 mA
—
0.2
0.4
V
—
—
±10
µA
Input Leakage Current
IL
Enable Input High Current
IENH
VENx = VIH
—
4
—
µA
Enable Input Low Current
IENL
VENx = VIL
—
20
—
µA
DC Supply Current (All inputs 0 V or at supply)
Si8430/35-A,-B,-C, VDD1
All inputs 0 DC
—
7
10
mA
Si8430/35-A,-B,-C, VDD2
All inputs 0 DC
—
6
9
mA
Si8430/35-A,-B,-C, VDD1
All inputs 1 DC
—
13
17
mA
Si8430/35-A,-B,-C, VDD2
All inputs 1 DC
—
5
8
mA
Si8431-A,-B,-C, VDD1
All inputs 0 DC
—
7
11
mA
Si8431-A,-B,-C, VDD2
All inputs 0 DC
—
10
15
mA
Si8431-A,-B,-C, VDD1
All inputs 1 DC
—
12
18
mA
Si8431-A,-B,-C, VDD2
All inputs 1 DC
—
11
16
mA
10 Mbps Supply Current (All inputs = 5 MHz square wave, CI = 15 pF on all outputs)
Si8430/35-B,-C, VDD1
—
10
14
mA
Si8430/35-B,-C, VDD2
—
11
16
mA
Si8431-B,-C, VDD1
—
10
15
mA
Si8431-B,-C, VDD2
—
13
18
mA
100 Mbps Supply Current (All inputs = 50 MHz square wave, CI = 15 pF on all outputs)
Si8430-C, VDD1
—
11
15
mA
Si8430-C, VDD2
—
16
20
mA
Si8431-C, VDD1
—
12
18
mA
Si8431-C, VDD2
—
19
25
mA
Rev. 0.3
7
Si8430/31/35
Table 2. Electrical Characteristics (Continued)
(VDD1 = 3.3 V, VDD2 = 3.3 V, TA = –40 to 125 ºC)
Parameter
Symbol
Test Condition
Min
Typ
Max
Unit
Maximum Data Rate
0
—
1
Mbps
Minimum Pulse Width
—
—
1000
ns
Timing Characteristics
Si843x-A
Propagation Delay
tPHL, tPLH
See Figure 2
—
—
75
ns
PWD
See Figure 2
—
—
30
ns
tPSK(P-P)
—
—
50
ns
tPSK
—
—
40
ns
Maximum Data Rate
0
—
10
Mbps
Minimum Pulse Width
—
—
100
ns
Pulse Width Distortion
|tPLH - tPHL|
Propagation Delay Skew1
Channel-Channel Skew
Si843x-B
Propagation Delay
tPHL, tPLH
See Figure 2
—
—
35
ns
PWD
See Figure 2
—
—
7.5
ns
tPSK(P-P)
—
—
25
ns
tPSK
—
—
5
ns
Maximum Data Rate
0
—
150
Mbps
Minimum Pulse Width
—
—
6.6
ns
Pulse Width Distortion
|tPLH - tPHL|
Propagation Delay Skew1
Channel-Channel Skew
Si843x-C
Propagation Delay
Pulse Width Distortion
|tPLH - tPHL|
Propagation Delay Skew1
Channel-Channel Skew
8
tPHL, tPLH
See Figure 2
4
6.5
9.5
ns
PWD
See Figure 2
—
—
3
ns
tPSK(P-P)
—
—
5.5
ns
tPSK
—
—
3
ns
Rev. 0.3
Si8430/31/35
Table 2. Electrical Characteristics (Continued)
(VDD1 = 3.3 V, VDD2 = 3.3 V, TA = –40 to 125 ºC)
Parameter
Symbol
Test Condition
Min
Typ
Max
Unit
Output Rise Time
tr
CL = 15 pF
See Figure 2
—
2
—
ns
Output Fall Time
tf
CL = 15 pF
See Figure 2
—
2
—
ns
CTMI
VI = VDD or 0 V
25
30
—
kV/µs
Enable to Data Valid
ten1
See Figure 1
—
5
—
ns
Enable to Data Tri-State
ten2
See Figure 1
—
5
—
ns
—
3
—
µs
For All Models
Common Mode Transient
Immunity
Start-up Time
2
tSU
Notes:
1. tPSK(P-P) is the magnitude of the difference in propagation delay times measured between different units operating at
the same supply voltages, load, and ambient temperature.
2. Start-up time is the time period from the application of power to valid data at the output.
Rev. 0.3
9
Si8430/31/35
Table 3. Electrical Characteristics
(VDD1 = 2.5 V, VDD2 = 2.5 V, TA = –40 to 100 ºC)
Parameter
Symbol
Test Condition
Min
Typ
Max
Unit
High Level Input Voltage
VIH
2.0
—
—
V
Low Level Input Voltage
VIL
—
—
0.8
V
High Level Output Voltage
VOH
loh = –4 mA
VDD1,VDD2 – 0.4
2.3
—
V
Low Level Output Voltage
VOL
lol = 4 mA
—
0.2
0.4
V
—
—
±10
µA
Input Leakage Current
IL
Enable Input High Current
IENH
VENx = VIH
—
4
—
µA
Enable Input Low Current
IENL
VENx = VIL
—
20
—
µA
DC Supply Current (All inputs 0 V or at supply)
Si8430/35-A,-B,-C, VDD1
All inputs 0 DC
—
6
8
mA
Si8430/35-A,-B,-C, VDD2
All inputs 0 DC
—
5
7
mA
Si8430/35-A,-B,-C, VDD1
All inputs 1 DC
—
11
13
mA
Si8430/35-A,-B,-C, VDD2
All inputs 1 DC
—
5
7
mA
Si8431-A,-B,-C, VDD1
All inputs 0 DC
—
7
10
mA
Si8431-A,-B,-C, VDD2
All inputs 0 DC
—
9
11
mA
Si8431-A,-B,-C, VDD1
All inputs 1 DC
—
11
13
mA
Si8431-A,-B,-C, VDD2
All inputs 1 DC
—
9
11
mA
10 Mbps Supply Current (All inputs = 5 MHz square wave, CI = 15 pF on all outputs)
Si8430/35-B,-C, VDD1
—
9
11
mA
Si8430/35-B,-C, VDD2
—
8
10
mA
Si8431-B,-C, VDD1
—
9
11
mA
Si8431-B,-C, VDD2
—
10
13
mA
100 Mbps Supply Current (All inputs = 50 MHz square wave, CI = 15 pF on all outputs)
Si8430-C, VDD1
—
10
12
mA
Si8430-C, VDD2
—
12
15
mA
Si8431-C, VDD1
—
12
15
mA
Si8431-C, VDD2
—
15
19
mA
10
Rev. 0.3
Si8430/31/35
Table 3. Electrical Characteristics (Continued)
(VDD1 = 2.5 V, VDD2 = 2.5 V, TA = –40 to 100 ºC)
Parameter
Symbol
Test Condition
Min
Typ
Max
Unit
Maximum Data Rate
0
—
1
Mbps
Minimum Pulse Width
—
—
1000
ns
Timing Characteristics
Si843x-A
Propagation Delay
tPHL, tPLH
See Figure 2
—
—
75
ns
PWD
See Figure 2
—
—
30
ns
tPSK(P-P)
—
—
50
ns
tPSK
—
—
40
ns
Maximum Data Rate
0
—
10
Mbps
Minimum Pulse Width
—
—
100
ns
Pulse Width Distortion
|tPLH - tPHL|
Propagation Delay Skew1
Channel-Channel Skew
Si843x-B
Propagation Delay
tPHL, tPLH
See Figure 2
—
—
35
ns
PWD
See Figure 2
—
—
7.5
ns
tPSK(P-P)
—
—
25
ns
tPSK
—
—
5
ns
Maximum Data Rate
0
—
100
Mbps
Minimum Pulse Width
—
—
10
ns
Pulse Width Distortion
|tPLH - tPHL|
Propagation Delay Skew1
Channel-Channel Skew
Si843x-C
Propagation Delay
Pulse Width Distortion
|tPLH - tPHL|
Propagation Delay Skew1
Channel-Channel Skew
tPHL, tPLH
See Figure 2
5
10
17
ns
PWD
See Figure 2
—
—
7
ns
tPSK(P-P)
—
—
12
ns
tPSK
—
—
4
ns
Rev. 0.3
11
Si8430/31/35
Table 3. Electrical Characteristics (Continued)
(VDD1 = 2.5 V, VDD2 = 2.5 V, TA = –40 to 100 ºC)
Parameter
Symbol
Test Condition
Min
Typ
Max
Unit
Output Rise Time
tr
CL = 15 pF
See Figure 2
—
2
—
ns
Output Fall Time
tf
CL = 15 pF
See Figure 2
—
2
—
ns
CTMI
VI = VDD or 0 V
25
30
—
kV/µs
Enable to Data Valid
ten1
See Figure 1
—
5
—
ns
Enable to Data Tri-State
ten2
See Figure 1
—
5
—
ns
Start-up Time2
tSU
—
3
—
µs
For All Models
Common Mode Transient
Immunity
Notes:
1. tPSK(P-P) is the magnitude of the difference in propagation delay times measured between different units operating at the
same supply voltages, load, and ambient temperature.
2. Start-up time is the time period from the application of power to valid data at the output.
12
Rev. 0.3
Si8430/31/35
Table 4. Absolute Maximum Ratings
Parameter
Symbol
Min
Typ
Max
Unit
TSTG
–65
—
150
ºC
TA
–40
—
125
ºC
VDD1, VDD2
–0.5
—
6
V
Input Voltage
VI
–0.5
—
VDD + 0.5
V
Output Voltage
VO
–0.5
—
VDD + 0.5
V
Output Current Drive Channel
LO
—
—
10
mA
Lead Solder Temperature (10s)
—
—
260
ºC
Maximum Isolation Voltage
—
—
4000
VDC
Storage Temperature
Operating Temperature
Supply Voltage
Note: Permanent device damage may occur if the above Absolute Maximum Ratings are exceeded. Functional operation
should be restricted to conditions as specified in the operational sections of this data sheet.
Table 5. Recommended Operating Conditions
Parameter
Ambient Operating Temperature*
Supply Voltage
Symbol
Test Condition
Min
Typ
Max
Unit
TA
100 Mbps, 15 pF, 5 V
–40
25
125
ºC
150 Mbps, 15 pF, 5 V
0
25
100
ºC
VDD1
2.375
—
5.5
V
VDD2
2.375
—
5.5
V
*Note: The maximum ambient temperature is dependent on data frequency, output loading, number of operating channels,
and supply voltage.
Rev. 0.3
13
Si8430/31/35
Table 6. Regulatory Information
CSA
The Si84xx is certified under CSA Component Acceptance Notice. For more details, see File 232873.
VDE
The Si84xx is certified according to IEC 60747-5-2. For more details, see File 5006301-4880-0001.
UL
The Si84xx is certified under UL1577 component recognition program to provide basic insulation to 2500 VRMS
(1 minute). It is production tested > 3000 VRMS for 1 second. For more details, see File E257455.
Table 7. Insulation and Safety-related Specifications
Parameter
Symbol
Test Condition
Value
Unit
Minimum Air Gap (Clearance)
L(IO1)
7.7 min
mm
Minimum External Tracking (Creepage)
L(IO2)
8.1
mm
0.008
min
mm
>175
V
1012
Ω
1.4
pF
4.0
pF
Minimum Internal Gap (Internal Clearance)
Tracking Resistance (Comparative Tracking
Index)
CTI
Resistance (Input-Output)1
RIO
1
Capacitance (Input-Output)
Input Capacitance2
DIN IEC 60112/VDE 0303 Part 1
CIO
f = 1 MHz
CI
Notes:
1. To determine resistance and capacitance, the Si84xx is converted into a 2-terminal device. Pins 1–8 are shorted
together to form the first terminal and pins 9–16 are shorted together to form the second terminal. The parameters are
then measured between these two terminals.
2. Measured from input pin to ground.
14
Rev. 0.3
Si8430/31/35
Table 8. IEC 60664-1 (VDE 0884 Part 2) Ratings
Parameter
Basic isolation group
Installation Classification
Test Conditions
Specification
Material Group
IIIa
Rated Mains Voltages < 150 VRMS
I-IV
Rated Mains Voltages < 300 VRMS
I-III
Rated Mains Voltages < 400 VRMS
I-II
Table 9. IEC 60747-5-2 Insulation Characteristics*
Parameter
Maximum Working Insulation Voltage
Input to Output Test Voltage
Highest Allowable Overvoltage (Transient
Overvoltage, tTR = 10 sec)
Symbol
Test Condition
VIORM
VPR
Characteristic
Unit
560
V peak
Method a
After Environmental Tests
Subgroup 1
(VIORM x 1.6 = VPR, tm = 60 sec,
Partial Discharge < 5 pC)
896
Method b1
(VIORM x 1.875 = VPR, 100%
Production Test, tm = 1 sec,
Partial Discharge < 5 pC)
1050
After Input and/or Safety Test
Subgroup 2/3
(VIORM x 1.2 = VPR, tm = 60 sec,
Partial Discharge < 5 pC)
672
4000
VTR
Pollution Degree (DIN VDE 0110, Table 1)
Insulation Resistance at TS, VIO = 500 V
V peak
V peak
2
>109
RS
Ω
*Note: This isolator is suitable for basic electrical isolation only within the safety limit data. Maintenance of the safety data is
ensured by protective circuits. The Si84xx provides a climate classification of 40/125/21.
Table 10. IEC Safety Limiting Values
Parameter
Symbol
Case Temperature
TS
Safety input, output, or supply current
IS
Test Condition
θJA = 107 °C/W,
VI = 5.5 V,
TJ = 150 °C,
TA = 25 °C
Min
Typ
Max
Unit
—
—
150
°C
—
—
210
mA
*Note: Maximum value allowed in the event of a failure; also see the thermal derating curve in Figure 3.
Rev. 0.3
15
Si8430/31/35
Table 11. Thermal Characteristics
Parameter
Symbol
Test Condition
Min
Typ
Max
Unit
IC Junction-to-Case Thermal Resistance
θJC
Thermocouple located
at center of package
—
45
—
ºC/W
IC Junction-to-Air Thermal Resistance
θJA
—
107
—
ºC/W
Device Power Dissipation*
PD
—
—
250
mW
200
175 162
110
125
130
Safety-Limiting Current (mA)
*Note: The Si8430-C-IS is tested with VDD1 = VDD2 = 5.5 V, TJ = 150 ºC, CL = 15 pF, input a 150 Mbps 50% duty cycle
square wave.
150
2.75 V
125
5.5 V
100
3.6 V
75
50
25
0
0
50
100
150
200
Figure 3. Thermal Derating Curve, Dependence of Safety Limiting Values
with Case Temperature per DIN EN 60747-5-2
16
Rev. 0.3
Si8430/31/35
2. Typical Performance Characteristics
15
19
11
3.3V
9
2.5V
7
5V
17
5V
Current (mA)
Current (mA)
13
15
3.3V
13
11
2.5V
9
7
5
5
0
10
20
30
40
50
60
70
80
90
100
0
10
20
30
Data Rate (Mbps)
50
60
70
80
90
100
Figure 6. Si8431 Typical VDD1 Supply Current
vs. Data Rate 5, 3.3,
and 2.5 V Operation
Figure 4. Si8430/35 Typical VDD1 Supply
Current vs. Data Rate 5, 3.3, and 2.5 V
Operation
25
19
5V
20
5V
17
Current (mA)
Current (mA)
40
Data Rate (Mbps)
3.3V
15
10
2.5V
5
3.3V
15
13
2.5V
11
9
7
0
5
0
10
20
30
40
50
60
70
80
90
100
0
Data Rate (Mbps)
Figure 5. Si8430/35 Typical VDD2 Supply
Current vs. Data Rate 5, 3.3, and 2.5 V
Operation (15 pF Load)
10
20
30
40
50
60
70
80
90
100
Data Rate (Mbps)
Figure 7. Si8431 Typical VDD2 Supply Current
vs. Data Rate 5, 3.3,
and 2.5 V Operation (15 pF Load)
Rev. 0.3
17
Si8430/31/35
10
Delay (ns)
9
8
Falling Edge
7
6
Rising Edge
5
-40
-20
0
20
40
60
80
100
120
Temperature (Degrees C)
Figure 8. Propagation Delay
vs. Temperature 5 V Operation
10
Delay (ns)
9
Rising Edge
8
Falling Edge
7
6
5
-40
-20
0
20
40
60
80
100
120
Temperature (Degrees C)
Figure 9. Propagation Delay
vs. Temperature 3.3 V Operation
15
Delay (ns)
13
Rising Edge
11
Falling Edge
9
7
5
-40
-20
0
20
40
60
80
100
120
Temperature (Degrees C)
Figure 10. Propagation Delay
vs. Temperature 2.5 V Operation
18
Rev. 0.3
Si8430/31/35
3. Application Information
3.1. Theory of Operation
The operation of an Si8430 channel is analogous to that of an opto coupler, except an RF carrier is modulated
instead of light. This simple architecture provides a robust isolated data path and requires no special
considerations or initialization at start-up. A simplified block diagram for a single Si8430 channel is shown in
Figure 11. A channel consists of an RF transmitter and receiver separated by a transformer.
Referring to the transmitter, input A modulates the carrier provided by an RF oscillator using on/off keying and
applies the resulting waveform to the primary of the transformer. The receiver contains a demodulator that decodes
the input state according to its RF energy content and applies the result to output B via the output driver.
TRANSMITTER
RF
OSCILLATOR
A
RECEIVER
MODULATOR
DEMODULATOR
B
Figure 11. Simplified Channel Diagram
3.2. Eye Diagram
Figure 12 illustrates an eye-diagram taken on an Si8430. The test used an Anritsu (MP1763C) Pulse Pattern
Generator for the data source. The output of the generator's clock and data from an Si8430 were captured on an
oscilloscope. The results illustrate that data integrity was maintained even at the high data rate of 150 Mbps. The
results also show that very low pulse width distortion and very little jitter were exhibited.
Figure 12. Eye Diagram
Rev. 0.3
19
Si8430/31/35
4. Layout Recommendations
Dielectric isolation is a set of specifications produced by the safety regulatory agencies from around the world that
describes the physical construction of electrical equipment that derives power from a high-voltage power system
such as 100–240 VAC systems or industrial power systems. The dielectric test (or HIPOT test) given in the safety
specifications places a very high voltage between the input power pins of a product and the user circuits and the
user touchable surfaces of the product. For the IEC relating to products deriving their power from the 220–240 V
power grids, the test voltage is 2500 VAC (or 3750 VDC—the peak equivalent voltage).
There are two terms described in the safety specifications:
Creepage—the distance along the insulating surface an arc may travel.
Clearance—the distance through the shortest path through air that an arc may travel.
Figure 13 illustrates the accepted method of providing the proper creepage distance along the surface. For a
220–240 V application, this distance is 8 mm and the wide body SOIC package must be used. There must be no
copper traces within this 8 mm exclusion area, and the surface should have a conformal coating such as solder
resist. The digital isolator chip must straddle this exclusion area.
Figure 13. Creepage Distance
4.1. Supply Bypass
The Si843x requires a 0.1 µF bypass capacitor between VDD1 and GND1 and VDD2 and GND2. The capacitor
should be placed as close as possible to the package.
20
Rev. 0.3
Si8430/31/35
4.2. Input and Output Characteristics
The Si843x inputs and outputs are standard CMOS drivers/receivers. The Si844x inputs and outputs are standard
CMOS drivers/receivers. Table 12 details powered and unpowered operation of the Si84xx.
Table 12. Si84xx Operation Table
VI
Input1,2
EN
Input1,2,3,4
VDDI
State1,5,6
VDDO
State1,5,6
VO
Output1,2
H
H or NC
P
P
H
L
H or NC
P
P
L
X
L
P
P
Hi-Z
X
H or NC
UP
P
L
X
L
UP
P
Hi-Z
X
X
P
UP
L
Comments
Enabled, normal operation.
Disabled
Upon the transition of VDDI from unpowered to
powered, VO returns to the same state as VI in
less than 1 µs.
Disabled
Upon the transition of VDDI from unpowered to
powered, VO returns to the same state as VI in
less than 1 µs, if EN is in either the H or NC state.
Notes:
1. VDDI and VDDO are the input and output power supplies. VI and VO are the respective input and output terminals. EN
is the enable control input located on the same output side.
2. X = not applicable; H = Logic High; L = Logic Low; Hi-Z = High Impedance.
3. It is recommended that the enable inputs be connected to an external logic high or low level when the Si84xx is
operating in noisy environments.
4. No Connect (NC) replaces EN1 on Si8430/35. No Connect replaces EN2 on the Si8435. No Connects are not internally
connected and can be left floating, tied to VDD, or tied to GND.
5. "Powered" state (P) is defined as 2.375 V < VDD < 5.5 V.
6. "Unpowered" state (UP) is defined as VDD = 0 V.
Rev. 0.3
21
Si8430/31/35
4.3. Enable (EN1, EN2) Inputs
Enable inputs EN1 and EN2 can be used for multiplexing, for clock sync, or other output control. EN1, EN2 logic
operation is summarized for each isolator product in Table 13. These inputs are internally pulled-up to local VDD by
a 9 µA current source allowing them to be connected to an external logic level (high or low) or left floating. To
minimize noise coupling, do not connect circuit traces to EN1 or EN2 if they are left floating. If EN1, EN2 are
unused, it is recommended they be connected to an external logic level, especially if the Si84xx is operating in a
noisy environment.
Table 13. Enable Input Truth Table
P/N
EN1*
EN2*
Si8430
—
H
Outputs B1, B2, B3 are enabled.
—
L
Outputs B1, B2, B3 are disabled and in high impedance state.
H
X
Output A3 enabled.
L
X
Output A3 disabled and in high impedance state.
X
H
Outputs B1, B2 are enabled.
X
L
Outputs B1, B2 are disabled and in high impedance state.
—
—
Outputs B1, B2, B3 are enabled.
Si8431
Si8435
Operation
*Note: X = not applicable; H = Logic High; L = Logic Low.
22
Rev. 0.3
Si8430/31/35
4.4. RF Radiated Emissions
The Si8430 family uses a RF carrier frequency of approximately 2.1 GHz. This will result in a small amount of
radiated emissions at this frequency and its harmonics. The radiation is not from the IC chip but due to a small
amount of RF energy driving the isolated ground planes which can act as a dipole antenna.
The unshielded Si8430 evaluation board passes FCC requirements. Table 14 shows measured emissions
compared to FCC requirements.
Radiated emissions can be reduced if the circuit board is enclosed in a shielded enclosure or if the PCB is a less
efficient antenna.
Table 14. Radiated Emissions
Frequency
(GHz)
Measured
(dBµV/m)
FCC Spec
(dBµV/m)
Compared
to Spec
(dB)
2.094
70.0
74.0
–4.0
2.168
68.3
74.0
–5.7
4.210
61.9
74.0
–12.1
4.337
60.7
74.0
–13.3
6.315
58.3
74.0
–15.7
6.505
60.7
74.0
–13.3
8.672
45.6
74.0
–28.4
Rev. 0.3
23
Si8430/31/35
4.5. RF Immunity and Common Mode Transient Immunity
The Si8430 family has very high common mode transient immunity while transmitting data. This is typically
measured by applying a square pulse with very fast rise/fall times between the isolated grounds. Measurements
show no failures up to 30 kV/µs. During a high surge event the output may glitch low for up to 20–30 ns, but the
output corrects immediately after the surge event.
The Si843x family passes the industrial requirements of CISPR24 for RF immunity of 3 V/m using an unshielded
evaluation board. As shown in Figure 14, the isolated ground planes form a parasitic dipole antenna, while
Figure 15 shows the RMS common mode voltage versus frequency above which the Si843x becomes susceptible
to data corruption. To avoid compromising data, care must be taken to keep RF common-mode voltage below the
envelope specified in Figure 15. The PCB should be laid-out to not act as an efficient antenna for the RF frequency
of interest. RF susceptibility is also significantly reduced when the end system is housed in a metal enclosure, or
otherwise shielded.
GND1
Isolator
GND2
Dipole
Antenna
Figure 14. Dipole Antenna
RMS Voltage (V)
5
4
3
2
1
0
500
1000
1500
Frequency (MHz)
Figure 15. RMS Common Mode Voltage vs. Frequency
24
Rev. 0.3
2000
Si8430/31/35
5. Pin Descriptions
VDD1
GND1
A1
A2
A3
NC
EN1/NC
GND1
16
15
14
13
12
11
10
9
1
2
3
4
5
6
7
8
VDD2
GND2
B1
B2
B3
NC
EN2/NC
GND2
Top View
Wide Body SOIC
Name
SOIC-16 Pin#
Type
Description
VDD1
1
Supply
Side 1 power supply.
GND1
2
Ground
Side 1 ground.
A1
3
Digital Input
Side 1 digital input.
A2
4
Digital Input
Side 1 digital input.
A3
5
Digital I/O
NC
6
NA
EN1/NC*
7
Digital Input
GND1
8
Ground
Side 1 ground.
GND2
9
Ground
Side 2 ground.
EN2/NC*
10
Digital Input
NC
11
NA
B3
12
Digital I/O
B2
13
Digital Output
Side 2 digital output.
B1
14
Digital Output
Side 2 digital output.
GND2
15
Ground
Side 2 ground.
VDD2
16
Supply
Side 2 power supply.
Side 1 digital input or output.
No Connect.
Side 1 active high enable. NC on Si8430/35
Side 2 active high enable. NC on Si8435.
No Connect.
Side 2 digital input or output.
*Note: No Connect. These pins are not internally connected. They can be left floating, tied to VDD or tied to GND.
Rev. 0.3
25
Si8430/31/35
6. Ordering Guide
Ordering Part
Number
Number of Inputs Number of Inputs
VDD1 Side
VDD2 Side
Maximum
Data Rate
Temperature
Package
Type
Si8430-A-IS
3
0
1
–40 to 125 °C
SOIC-16
Si8430-B-IS
3
0
10
–40 to 125 °C
SOIC-16
Si8430-C-IS
3
0
150
–40 to 125 °C
SOIC-16
Si8431-A-IS
2
1
1
–40 to 125 °C
SOIC-16
Si8431-B-IS
2
1
10
–40 to 125 °C
SOIC-16
Si8431-C-IS
2
1
150
–40 to 125 °C
SOIC-16
Si8435-B-IS
3
0
10
–40 to 125 °C
SOIC-16
Note: All packages are Pb-free and RoHS Compliant. Moisture sensitivity level is MSL2 with peak reflow temperature of
260 °C according to the JEDEC industry standard classifications, and peak solder temperature.
26
Rev. 0.3
Si8430/31/35
7. Package Outline: Wide Body SOIC
Figure 16 illustrates the package details for the Quad-Channel Digital Isolator. Table 14 lists the values for the
dimensions shown in the illustration.
Figure 16. 16-Pin Wide Body SOIC
Table 14. Package Diagram Dimensions
Millimeters
Symbol
Min
Max
A
—
2.65
A1
0.1
0.3
D
10.3 BSC
E
10.3 BSC
E1
7.5 BSC
b
0.31
0.51
c
0.20
0.33
e
1.27 BSC
h
0.25
0.75
L
0.4
1.27
θ
0°
7°
Rev. 0.3
27
Si8430/31/35
DOCUMENT CHANGE LIST
Revision 0.1 to Revision 0.11
Updated Table 7, “Regulatory Information,” on
page 14.
Minor typographical edits.
Revision 0.11 to Revision 0.2
Updated Supply Current specifications in Table 1,
“Electrical Characteristics,” on page 4, Table 2,
“Electrical Characteristics,” on page 7, and Table 3,
“Electrical Characteristics,” on page 10.
Updated performance plots in Figures 4, 5, 6, and 7.
Added NC note (Note 3) to Table 10, “Si84xx Truth
Table (Positive Logic),” on page 16.
Added NC note (*) to "5. Pin Descriptions" on page
25.
Revision 0.2 to Revision 0.3
Updated Notes to Tables 1, 2, & 3.
Updated Figure 2.
Updated Tables 6–11 to clarify specifications, test
limits, & device characteristics.
28
Rev. 0.3
Si8430/31/35
NOTES:
Rev. 0.3
29
Si8430/31/35
CONTACT INFORMATION
Silicon Laboratories Inc.
400 West Cesar Chavez
Austin, TX 78701
Tel: 1+(512) 416-8500
Fax: 1+(512) 416-9669
Toll Free: 1+(877) 444-3032
Email: [email protected]
Internet: www.silabs.com
The information in this document is believed to be accurate in all respects at the time of publication but is subject to change without notice.
Silicon Laboratories assumes no responsibility for errors and omissions, and disclaims responsibility for any consequences resulting from
the use of information included herein. Additionally, Silicon Laboratories assumes no responsibility for the functioning of undescribed features
or parameters. Silicon Laboratories reserves the right to make changes without further notice. Silicon Laboratories makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does Silicon Laboratories assume any liability
arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation consequential or incidental damages. Silicon Laboratories products are not designed, intended, or authorized for use in applications intended to
support or sustain life, or for any other application in which the failure of the Silicon Laboratories product could create a situation where personal injury or death may occur. Should Buyer purchase or use Silicon Laboratories products for any such unintended or unauthorized application, Buyer shall indemnify and hold Silicon Laboratories harmless against all claims and damages.
Silicon Laboratories and Silicon Labs are trademarks of Silicon Laboratories Inc.
Other products or brandnames mentioned herein are trademarks or registered trademarks of their respective holders.
30
Rev. 0.3