HP HCPL-314J-XXXE 0.4 amp output current igbt gate drive optocoupler Datasheet

0.4 Amp Output Current
IGBT Gate Drive Optocoupler
Technical Data
HCPL-314J
Features
• 0.4 A Minimum Peak
Output Current
• High Speed Response:
0.7 µs Max. Propagation
Delay over Temp. Range
• Ultra High CMR: Min.
10 kV/µs at VCM = 1.5 kV
• Bootstrappable Supply
Current: Max. 3 mA
• Wide Operating Temp.
Range: -40°C to 100°C
• Wide VCC Operating Range:
10 V to 30 V over Temp.
Range
• Available in DIP8 (Single)
and SO16 (Dual) Package
• Safety Approvals: UL
Recognized, 3750 Vrms for
1 Minute. CSA Approval.
IEC/EN/DIN EN 60747-5-2
Approval VIORM=891 V peak
Functional Diagram
Description
The HCPL-314J family of devices
consists of an AlGaAs LED
optically coupled to an integrated
circuit with a power output stage.
These optocouplers are ideally
suited for driving power IGBTs
and MOSFETs used in motor
control inverter applications. The
high operating voltage range of
the output stage provides the
drive voltages required by gate
controlled devices. The voltage
and current supplied by this
optocoupler makes it ideally
suited for directly driving small
or medium power IGBTs. For
IGBTs with higher ratings the
HCPL-3150(0.5A) or HCPL-3120
(2.0A) optocouplers can be used.
N/C
1
16 VCC
ANODE
2
15 VO
CATHODE
3
ANODE
6
11 VCC
CATHODE
7
10 VO
N/C
8
14 VEE
SHIELD
9
SHIELD
HCPL-314J
Truth Table
LED
VO
OFF
LOW
ON
HIGH
Applications
• Isolated IGBT/Power
MOSFET Gate Drive
• AC and Brushless DC Motor
Drives
• Inverters for Appliances
• Industrial Inverters
• Switch Mode Power
Supplies (SMPS)
• Uninterruptable Power
Supplies (UPS)
A 0.1 µF bypass capacitor must be connected between pins VCC and V EE.
CAUTION: It is advised that normal static precautions be taken in handling and assembly of this component to prevent
damage and/or degradation which may be induced by ESD.
VEE
2
Selection Guide
Package Type
SO16
Part Number
HCPL-314J
Number of Channels
2
Ordering Information
Specify part number followed by option number (if desired)
Example:
HCPL-314J#YYYY
No option = SO16 Package.
500 = Tape and Reel Packaging Option.
XXXE = Lead Free Option
Remarks: The notation “#” is used for existing products, while (new) products launched since 15th July 2001 and lead free option will use “–”
Package Outline Drawing
HCPL-314J SO16 Package:
LAND PATTERN RECOMMENDATION
8.76 ± 0.20
(0.345 ± 0.008)
11 10
9
VO2
VCC2
GND1
VO1
VCC1
16 15 14
GND2
TOP VIEW
7.49 ± 0.10
(0.295 ± 0.004)
NC
VIN1
V1
VIN2
V2
NC
HCPL-314J
1
2
3
6
7
8
11.63 (0.458)
2.16 (0.085)
0.64 (0.025)
0.10 - 0.30
(0.004 - 0.0118)
STANDOFF
8.76 ± 0.20
(0.345 ± 0.008)
VIEW
FROM
PIN 16
0 - 8°
9°
0.23
(0.0091)
0.64
(0.025 MIN.)
VIEW
FROM
PIN 1
3.51 ± 0.13
(0.138 ± 0.005)
1.27
0.457
(0.050)
(0.018)
0.016 ± 0.0003
(0.406 ± 0.007)
10.36 ± 0.20
(0.408 ± 0.008)
ALL LEADS TO BE COPLANAR ± 0.05 mm (0.002 INCHES) .
DIMENSIONS IN MILLIMETERS AND (INCHES).
NOTE: FLOATING LEAD PROTRUSION IS 0.25 mm (10 mils) MAX.
3
Regulatory Information
Solder Reflow Thermal Profile
The HCPL-314J has been
approved by the following
organizations:
300
TEMPERATURE (°C)
PREHEATING RATE 3°C + 1°C/–0.5°C/SEC.
REFLOW HEATING RATE 2.5°C ± 0.5°C/SEC.
PEAK
TEMP.
245°C
PEAK
TEMP.
240°C
2.5°C ± 0.5°C/SEC.
SOLDERING
TIME
200°C
30
SEC.
160°C
150°C
140°C
30
SEC.
3°C + 1°C/–0.5°C
100
PREHEATING TIME
150°C, 90 + 30 SEC.
50 SEC.
TIGHT
TYPICAL
LOOSE
ROOM
TEMPERATURE
0
50
0
100
150
200
TIME (SECONDS)
Recommended Pb-Free IR Profile
tp
Tp
TL
TEMPERATURE
IEC/EN/DIN EN 60747-5-2
Approved under:
IEC 60747-5-2:1997 + A1:2002
EN 60747-5-2:2001 + A1:2002
DIN EN 60747-5-2 (VDE 0884
Teil 2):2003-01.
PEAK
TEMP.
230°C
200
Tsmax
TIME WITHIN 5 °C of ACTUAL
PEAK TEMPERATURE
20-40 SEC.
260 +0/-5 °C
217 °C
RAMP-UP
3 °C/SEC. MAX.
150 - 200 °C
RAMP-DOWN
6 °C/SEC. MAX.
Tsmin
ts
PREHEAT
60 to 180 SEC.
tL
60 to 150 SEC.
25
t 25 °C to PEAK
TIME
NOTES:
THE TIME FROM 25 °C to PEAK TEMPERATURE = 8 MINUTES MAX.
Tsmax = 200 °C, Tsmin = 150 °C
250
UL
Approval under UL 1577,
component recognition program
up to VISO = 3750 Vrms. File
E55361.
CSA
Approved under CSA Component
Acceptance Notice #5, File CA
88324.
4
IEC/EN/DIN EN 60747-5-2 Insulation Characteristics
Description
Symbol
Installation classification per DIN VDE 0110/1.89, Table 1
for rated mains voltage ≤ 150 Vrms
for rated mains voltage ≤ 300 Vrms
for rated mains voltage ≤ 600 Vrms
Characteristic
Unit
I - IV
I - III
I-II
Climatic Classification
55/100/21
Pollution Degree (DIN VDE 0110/1.89)
Maximum Working Insulation Voltage
2
VIORM
891
Vpeak
Input to Output Test Voltage, Method b*
VIORM x 1.875=V PR, 100% Production Test with
tm=1 sec, Partial discharge < 5 pC
V PR
1670
Vpeak
Input to Output Test Voltage, Method a*
VIORM x 1.5=VPR, Type and Sample Test, tm=60 sec,
Partial discharge < 5 pC
V PR
1336
Vpeak
V IOTM
6000
Vpeak
TS
IS,INPUT
PS, OUTPUT
175
400
1200
°C
mA
mW
RS
>109
Ω
Highest Allowable Overvoltage
(Transient Overvoltage tini = 10 sec)
Safety-limiting values - maximum values allowed in the
event of a failure.
Case Temperature
Input Current**
Output Power**
Insulation Resistance at TS, VIO = 500 V
OUTPUT POWER – PS, INPUT CURRENT – IS
* Refer to the optocoupler section of the Isolation and Control Components Designer’s Catalog, under Product Safety Regulations
section, IEC/EN/DIN EN 60747-5-2, for a detailed description of Method a and Method b partial discharge test profiles.
** Refer to the following figure for dependence of PS and IS on ambient temperature.
800
PS (mW)
IS (mA)
700
600
500
400
300
200
100
0
0
25
50
75 100 125 150 175 200
TS – CASE TEMPERATURE – °C
5
Insulation and Safety Related Specifications
Parameter
Symbol
HCPL-314J
Units
Conditions
Minimum External Air Gap
(Clearance)
L(101)
8.3
mm
Measured from input terminals
to output terminals, shortest
distance through air.
Minimum External Tracking
(Creepage)
L(102)
8.3
mm
Measured from input terminals
to output terminals, shortest
distance path along body.
0.5
mm
Through insulation distance
conductor to conductor, usually
the straight line distance
thickness between the emitter
and detector.
>175
V
DIN IEC 112/VDE 0303 Part 1
Minimum Internal Plastic Gap
(Internal Clearance)
Tracking Resistance
(Comparative Tracking Index)
CTI
Isolation Group
IIIa
Material Group (DIN VDE
0110, 1/89, Table 1)
Absolute Maximum Ratings
Symbol
Min.
Max.
Units
Storage Temperature
Parameter
TS
-55
125
°C
Operating Temperature
TA
-40
100
°C
Average Input Current
IF(AVG)
25
mA
Peak Transient Input Current (<1 µs pulse
width, 300pps)
IF(TRAN)
1.0
A
Reverse Input Voltage
Note
1
VR
3
V
“High” Peak Output Current
IOH(PEAK)
0.6
A
2
“Low” Peak Output Current
IOL(PEAK)
0.6
A
2
Supply Voltage
VCC-VEE
-0.5
35
V
Output Voltage
VO(PEAK)
-0.5
VCC
V
PO
260
mW
3
PI
105
mW
4
Output Power Dissipation
Input Power Dissipation
Lead Solder Temperature
260°C for 10 sec., 1.6 mm below seating plane
Solder Reflow Temperature Profile
See Package Outline Drawings section
Recommended Operating Conditions
Parameter
Power Supply
Input Current (ON)
Input Voltage (OFF)
Operating Temperature
Symbol
VCC -VEE
IF(ON)
VF(OFF)
TA
Min.
10
8
-3.0
- 40
Max.
30
12
0.8
100
Units
V
mA
V
°C
Note
6
Electrical Specifications (DC)
Over recommended operating conditions unless otherwise specified.
Parameter
High Level Output Current
Symbol
IOH
Low Level Output Current
IOL
High Level Output Voltage
Low Level Output Voltage
High Level Supply Current
Low Level Supply Current
Threshold Input Current
Low to High
Threshold Input Voltage
High to Low
Input Forward Voltage
Temperature Coefficient of
Input Forward Voltage
Input Reverse Breakdown
Voltage
Input Capacitance
VOH
VOL
ICCH
ICCL
IFLH
Min.
0.2
0.4
0.2
0.4
VCC-4
Typ.
0.5
0.4
0.5
VCC-1.8
0.4
0.7
1.2
VFHL
0.8
VF
∆VF/∆TA
1.2
1.5
-1.2
BVR
3
10
Max.
Units
A
A
1
3
3
5
V
V
mA
mA
mA
Test
Conditions
Vo = V CC- 4
Vo = VCC-10
Vo = VEE+2.5
Vo = V EE+10
Io = -100 mA
Io = 100 mA
Io = 0 mA
Io = 0 mA
Io = 0 mA,
Vo>5 V
Fig.
2
3
5
6
1
4
7,8
Note
5
2
5
2
6,7
15
9,15
V
1.8
C IN
V
mV/°C
IF = 10 mA
V
IR = 100 µA
pF
f = 1 MHz,
VF = 0 V
16
Switching Specifications (AC)
Over recommended operating conditions unless otherwise specified.
Parameter
Propagation Delay Time to
High Output Level
Propagation Delay Time to
Low Output Level
Propagation Delay
Difference Between Any
Two Parts or Channels
Rise Time
Fall Time
Output High Level Common
Mode Transient Immunity
Output Low Level Common
Mode Transient Immunity
Symbol
tPLH
Min.
0.1
Typ.
0.2
Max.
0.7
Units
µs
tPHL
0.1
0.3
0.7
µs
PDD
-0.5
0.5
µs
tR
tF
|CMH|
10
30
ns
ns
kV/µs
|CML|
10
30
kV/µs
Test
Conditions
Rg = 47 Ω,
Cg = 3 nF,
f = 10 kHz,
Duty Cycle =
50%,
IF = 8 mA,
VCC = 30 V
TA = 25°C,
VCM = 1.5 kV
Fig. Note
10,11, 14
12,13,
14,17
10
18
18
11,
12
11,
13
7
Package Characteristics
For each channel unless otherwise specified.
Parameter
Input-Output Momentary
Withstand Voltage
Output-Output Momentary
Withstand Voltage
Input-Output Resistance
Input-Output Capacitance
Symbol
VISO
Min.
3750
VO-O
1500
RI-O
CI-O
Typ.
1012
1.2
Max.
Vrms
Test
Conditions
TA=25°C,
RH<50% for
1 min.
Ω
pF
VI-O=500 V
Freq=1 MHz
Units
Vrms
Fig.
Note
8,9
16
9
Notes:
1. Derate linearly above 70°C free air temperature at a rate of 0.3 mA/°C.
2. Maximum pulse width = 10 µs, maximum duty cycle = 0.2%. This value is intended to allow for component tolerances for designs
with IO peak minimum = 0.4 A. See Application section for additional details on limiting IOL peak.
3. Derate linearly above 85°C, free air temperature at the rate of 4.0 mW/°C.
4. Input power dissipation does not require derating.
5. Maximum pulse width = 50 µs, maximum duty cycle = 0.5%.
6. In this test, VOH is measured with a DC load current. When driving capacitive load VOH will approach VCC as IOH approaches zero
amps.
7. Maximum pulse width = 1 ms, maximum duty cycle = 20%.
8. In accordance with UL 1577, each HCPL-314J optocoupler is proof tested by applying an insulation test voltage ≥ 5000 Vrms for
1 second (leakage detection current limit II-O ≤ 5 µA). This test is performed before 100% production test for partial discharge
(method B) shown in the IEC/EN/DIN EN 60747-5-2 Insulation Characteristics Table, if applicable.
9. Device considered a two-terminal device: pins on input side shorted together and pins on output side shorted together.
10. PDD is the difference between tPHL and tPLH between any two parts or channels under the same test conditions.
11. Pins 3 and 4 (HCPL-314J) need to be connected to LED common.
12. Common mode transient immunity in the high state is the maximum tolerable |dVcm/dt| of the common mode pulse VCM to
assure that the output will remain in the high state (i.e. Vo > 6.0 V).
13. Common mode transient immunity in a low state is the maximum tolerable |dVCM/dt| of the common mode pulse, VCM , to assure
that the output will remain in a low state (i.e. Vo < 1.0 V).
14. This load condition approximates the gate load of a 1200 V/25 A IGBT.
15. For each channel. The power supply current increases when operating frequency and Qg of the driven IGBT increases.
16. Device considered a two terminal device: Channel one output side pins shorted together, and channel two output side pins shorted
together.
-0.5
-1.0
-1.5
-2.0
-25
0
25
50
75
100 125
0.34
0.32
0.30
-50
TA – TEMPERATURE – °C
Figure 1. VOH vs. Temperature.
50
75
100 125
0.40
-25
0
25
50
75
0.460
0.455
0.450
0.445
0.440
-50
100 125
Figure 4. V OL vs. Temperature.
-25
0
25
50
75
100 125
Figure 5. IOL vs. Temperature.
0.6
0.4
ICCL
0.2
ICCH
-25
0
25
50
75
100 125
TA – TEMPERATURE – °C
Figure 7. ICC vs. Temperature.
ICC – SUPPLY CURRENT – mA
0.8
-3
-4
-5
-6
0
0.4
0.6
20
15
10
5
0
0
0.8
0.6
0.4
ICCL
ICCH
0.2
15
20
25
VCC – SUPPLY VOLTAGE – V
Figure 8. ICC vs. VCC.
100 200 300 400 500 600 700
Figure 6. VOL vs. IOL .
1.0
0
10
0.2
IOH – OUTPUT HIGH CURRENT – A
IOL – OUTPUT LOW CURRENT – mA
1.2
1.0
-2
TA – TEMPERATURE – °C
1.4
1.2
VOH
-1
25
VOL – OUTPUT LOW VOLTAGE – V
0.41
0
Figure 3. V OH vs. IOH.
0.465
TA – TEMPERATURE – °C
ICC – SUPPLY CURRENT – mA
25
Figure 2. I OH vs. Temperature.
IOL – OUTPUT LOW CURRENT – A
0.42
0
-50
0
0.470
0.43
0.39
-50
-25
TA – TEMPERATURE – °C
0.44
VOL – OUTPUT LOW VOLTAGE – V
0.36
30
IFLH – LOW TO HIGH CURRENT THRESHOLD – mA
-2.5
-50
0.38
(VOH-VCC) – OUTPUT HIGH VOLTAGE DROP – V
0.40
0
IOH – OUTPUT HIGH CURRENT – A
(VOH-VCC) – HIGH OUTPUT VOLTAGE DROP – V
8
3.5
3.0
2.5
2.0
1.5
-50
-25
0
25
50
75
100 125
TA – TEMPERATURE – °C
Figure 9. IFLH vs. Temperature.
9
400
300
200
100
TPLH
TPHL
0
10
15
20
25
300
200
100
0
30
500
TP – PROPAGATION DELAY – ns
TP – PROPAGATION DELAY – ns
6
Figure 10. Propagation Delay vs. VCC.
350
TPLH
300
TPHL
250
0
50
100
150
200
Rg – SERIES LOAD RESISTANCE – Ω
Figure 13. Propagation Delay vs. Rg.
25
20
15
10
5
0
1.2
1.4
1.6
300
200
100
1.8
VF – FORWARD VOLTAGE – V
Figure 16. Input Current vs. Forward
Voltage.
-25
0
25
50
75
100 125
TA – TEMPERATURE – °C
Figure 12. Propagation Delay vs.
Temperature.
35
300
200
100
TPLH
TPHL
0
TPLH
TPHL
0
-50
18
400
TP – PROPAGATION DELAY – ns
TP – PROPAGATION DELAY – ns
15
Figure 11. Propagation Delay vs. IF .
400
IF – FORWARD CURRENT – mA
12
400
IF – FORWARD LED CURRENT – mA
VCC – SUPPLY VOLTAGE – V
200
9
VO – OUTPUT VOLTAGE – V
TP – PROPAGATION DELAY – ns
400
0
20
40
60
80
100
Cg – LOAD CAPACITANCE – nF
Figure 14. Propagation Delay vs. Cg.
30
25
20
15
10
5
0
-5
0
1
2
3
4
5
IF – FORWARD LED CURRENT – mA
Figure 15. Transfer Characteristics.
6
10
8
1
0.1 µF
IF = 7 to 16 mA
+
10 KHz –
500 Ω
2
+
–
7
IF
VCC = 15
to 30 V
tr
tf
VO
50% DUTY
CYCLE
6
3
90%
47 Ω
50%
VOUT
3 nF
4
10%
5
tPLH
tPHL
Figure 17. Propagation Delay Test Circuit and Waveforms.
VCM
5V
δt
0.1 µF
A
B
δV
8
1
IF
2
VO
3
6
4
5
VCC = 30 V
VO
–
Figure 18. CMR Test Circuit and Waveforms.
VOH
SWITCH AT A: IF = 10 mA
SWITCH AT B: IF = 0 mA
+
∆t
∆t
+
–
VO
VCM = 1500 V
VCM
0V
7
+
–
=
VOL
11
Applications Information
Eliminating Negative IGBT
Gate Drive
To keep the IGBT firmly off,
the HCPL-314J has a very low
maximum VOL specification of
1.0 V. Minimizing Rg and
the lead inductance from the
HCPL-314J to the IGBT gate and
emitter (possibly by mounting the
HCPL-314J on a small PC board
directly above the IGBT) can
eliminate the need for negative
HCPL-314J
+5 V
CONTROL
INPUT
IGBT gate drive in many
applications as shown in
Figure 19. Care should be taken
with such a PC board design to
avoid routing the IGBT collector
or emitter traces close to the
HCPL-314J input as this can
result in unwanted coupling of
transient signals into the input of
HCPL-314J and degrade
performance. (If the IGBT
drain must be routed near the
270 Ω
1
16
0.1 µF
2
+
–
FLOATING
SUPPLY
VCC = 18 V
HCPL-314J input, then the LED
should be reverse biased when in
the off state, to prevent the
transient signals coupled from
the IGBT drain from turning on
the HCPL-314J.) An external
clamp diode may be connected
between pins 14 & 15 and pins 9
& 10 (as shown in Figure 19) for
the protection of HCPL-314J in
the case of IGBTs switching
inductive load.
+ HVDC
15
Rg
74XX
OPEN
COLLECTOR
VOL
3
14
GND 1
+5 V
3-PHASE
AC
6
270 Ω
CONTROL
INPUT
11
0.1 µF
7
VCC = 18 V
+
–
10
Rg
74XX
OPEN
COLLECTOR
8
9
GND 1
Figure 19. Recommended LED Drive and Application Circuit for HCPL-314J.
- HVDC
Selecting the Gate Resistor (Rg)
Step 1: Calculate R g minimum from the IOL peak specification. The
IGBT and Rg in Figure 24 can be analyzed as a simple RC circuit with a
voltage supplied by the HCPL-314J.
Rg ≥
VCC – VOL
IOLPEAK
24 V – 5 V
=
0.6A
= 32 Ω
The VOL value of 5 V in the previous equation is the VOL at the peak
current of 0.6A. (See Figure 6).
Step 2: Check the HCPL-314J power dissipation and increase Rg if
necessary. The HCPL-314J total power dissipation (PT) is equal to the
sum of the emitter power (PE) and the output power (PO).
P T = PE + PO
PE = IF • VF • Duty Cycle
PO = PO(BIAS) + PO(SWITCHING) = ICC • VCC + ESW (Rg,Qg)• f
= (ICCBIAS + KICC • Qg • f) • VCC + E SW (Rg,Qg) • f
where KICC • Qg • f is the increase in ICC due to switching and KICC is a
constant of 0.001 mA/(nC*kHz). For the circuit in Figure 19 with IF
(worst case) = 10 mA, Rg = 32 Ω, Max Duty Cycle = 80%,
Qg = 100 nC, f = 20 kHz and TAMAX = 85°C:
PE = 10 mA • 1.8 V • 0.8 = 14 mW
P O = (3 mA + (0.001 mA/(nC • kHz)) • 20 kHz • 100 nC) • 24 V +
0.4 µJ • 20 kHz = 128 mW
< 260 mW (PO(MAX) @ 85°C)
The value of 3 mA for ICC in the previous equation is the max. I CC over
entire operating temperature range.
Since PO for this case is less than PO(MAX), Rg = 32 Ω is alright for the
power dissipation.
Esw – ENERGY PER SWITCHING CYCLE – µJ
12
4.0
Qg = 50 nC
Qg = 100 nC
Qg = 200 nC
Qg = 400 nC
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0
0
20
40
60
80
100
Rg – GATE RESISTANCE – Ω
Figure 20. Energy Dissipated in the HCPL314J and for Each IGBT Switching Cycle.
LED Drive Circuit
Considerations for Ultra High
CMR Performance
Without a detector shield, the
dominant cause of optocoupler
CMR failure is capacitive coupling
from the input side of the
optocoupler, through the package,
to the detector IC as shown in
Figure 21. The HCPL-314J
improves CMR performance by
using a detector IC with an
optically transparent Faraday
shield, which diverts the
capacitively coupled current away
from the sensitive IC circuitry.
However, this shield does not
eliminate the capacitive coupling
between the LED and optocoupler
pins 5-8 as shown in Figure 22.
This capacitive coupling causes
perturbations in the LED current
during common mode transients
and becomes the major source of
CMR failures for a shielded
optocoupler. The main design
objective of a high CMR LED drive
circuit becomes keeping the LED
in the proper state (on or off )
during common mode transients.
For example, the recommended
application circuit (Figure 19), can
achieve 10 kV/µs CMR while
minimizing component complexity.
Techniques to keep the LED in the
proper state are discussed in the
next two sections.
13
8
1
2
7
2
3
6
3
5
4
1
CLEDO1
8
CLEDP
CLEDP
7
CLEDO2
CLEDN
4
8
1
0.1
µF
CLEDP
2
+
VSAT
–
5
SHIELD
Figure 22. Optocoupler Input to Output
Capacitance Model for Shielded Optocouplers.
Figure 21. Optocoupler Input to Output
Capacitance Model for Unshielded Optocouplers.
+5 V
6
CLEDN
7
+
–
VCC = 18 V
ILEDP
3
4
•••
6
CLEDN
Rg
5
SHIELD
•••
* THE ARROWS INDICATE THE DIRECTION
OF CURRENT FLOW DURING –dVCM/dt.
+ –
VCM
Figure 23. Equivalent Circuit for Figure 17 During Common
Mode Transient.
8
1
+5 V
8
1
+5 V
CLEDP
2
3
Q1
CLEDN
CLEDP
7
2
6
3
5
4
7
CLEDN
6
ILEDN
4
SHIELD
Figure 24. Not Recommended Open Collector
Drive Circuit.
SHIELD
5
Figure 25. Recommended LED Drive Circuit for Ultra-High
CMR IPM Dead Time and Propagation Delay Specifications.
14
CMR with the LED On
(CMRH)
A high CMR LED drive circuit
must keep the LED on during
common mode transients. This is
achieved by overdriving the LED
current beyond the input
threshold so that it is not pulled
below the threshold during a
transient. A minimum LED
current of 8 mA provides
adequate margin over the
maximum IFLH of 5 mA to
achieve 10 kV/µs CMR.
CMR with the LED Off
(CMRL)
A high CMR LED drive
circuit must keep the LED off
(VF ≤ VF(OFF)) during common
mode transients. For example,
during a -dVCM/dt transient in
Figure 23, the current flowing
through CLEDP also flows
through the RSAT and VSAT of the
logic gate. As long as the low
state voltage developed across
the logic gate is less than VF(OFF)
the LED will remain off and no
common mode failure will occur.
The open collector drive circuit,
shown in Figure 24, can not keep
the LED off during a +dVCM /dt
transient, since all the current
flowing through CLEDN must be
supplied by the LED, and it is
not recommended for
applications requiring ultra high
CMR1 performance. The
alternative drive circuit which
like the recommended
application circuit (Figure 19),
does achieve ultra high CMR
performance by shunting the
LED in the off state.
IPM Dead Time and
Propagation Delay
Specifications
The HCPL-314J includes a
Propagation Delay Difference
(PDD) specification intended to
help designers minimize “dead
time” in their power inverter
designs. Dead time is the time
high and low side power
transistors are off. Any overlap
in Ql and Q2 conduction will
result in large currents flowing
through the power devices from
the high-voltage to the lowvoltage motor rails. To minimize
dead time in a given design, the
turn on of LED2 should be
delayed (relative to the turn off
of LED1) so that under worstcase conditions, transistor Q1
has just turned off when
transistor Q2 turns on, as shown
in Figure 26. The amount of
delay necessary to achieve this
condition is equal to the
maximum value of the
propagation delay difference
specification, PDD max, which is
specified to be 500 ns over the
operating temperature range of
-40° to 100°C.
Delaying the LED signal by the
maximum propagation delay
difference ensures that the
minimum dead time is zero, but it
does not tell a designer what the
maximum dead time will be. The
maximum dead time is equivalent
to the difference between the
maximum and minimum
propagation delay difference
specification as shown in
Figure 27. The maximum dead
time for the HCPL-314J is 1 µs
(= 0.5 µs - (-0.5 µs)) over the
operating temperature range of
-40°C to 100°C.
Note that the propagation delays
used to calculate PDD and dead
time are taken at equal
temperatures and test conditions
since the optocouplers under
consideration are typically
mounted in close proximity to
each other and are switching
identical IGBTs.
15
ILED1
VOUT1
Q1 ON
Q1 OFF
Q2 ON
VOUT2
ILED2
Q2 OFF
tPHL MAX
tPLH MIN
PDD* MAX = (tPHL- tPLH)MAX = tPHL MAX - tPLH MIN
*PDD = PROPAGATION DELAY DIFFERENCE
NOTE: FOR PDD CALCULATIONS THE PROPAGATION DELAYS
ARE TAKEN AT THE SAME TEMPERATURE AND TEST CONDITIONS.
Figure 26. Minimum LED Skew for Zero Dead Time.
ILED1
VOUT1
Q1 ON
Q1 OFF
Q2 ON
VOUT2
Q2 OFF
ILED2
tPHL MIN
tPHL MAX
tPLH
MIN
tPLH MAX
(tPHL-tPLH) MAX
PDD* MAX
MAXIMUM DEAD TIME
(DUE TO OPTOCOUPLER)
= (tPHL MAX - tPHL MIN) + (tPLH MAX - tPLH MIN)
= (tPHL MAX - tPLH MIN) – (tPHL MIN - tPLH MAX)
= PDD* MAX – PDD* MIN
*PDD = PROPAGATION DELAY DIFFERENCE
NOTE: FOR DEAD TIME AND PDD CALCULATIONS ALL PROPAGATION
DELAYS ARE TAKEN AT THE SAME TEMPERATURE AND TEST CONDITIONS.
Figure 27. Waveforms for Dead Time.
www.agilent.com/semiconductors
For product information and a complete list of
distributors, please go to our web site.
For technical assistance call:
Americas/Canada: +1 (800) 235-0312 or
(916) 788-6763
Europe: +49 (0) 6441 92460
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Data subject to change.
Copyright © 2005 Agilent Technologies, Inc.
Obsoletes 5989-0782EN
March 1, 2005
5989-2141EN
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