Datasheet IR2114SS, IR21141SS, IR2214SS, IR22141SS Datasheet (IOR)

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Data Sheet No. PD60213 revC
IR2114SS/ IR21141SS
HALF-BRIDGE GATE DRIVER IC
Features
Soft over-current shutdown
Synchronization signal to synchronize shut down with the other phases
Integrated desaturation detection circuit
Two stage turn on output for di/dt control
Separate pull-up/pull-down output drive pins
Matched delay outputs
Under voltage lockout with hysteresis band
Description
The IR2114/21141/2214/IR22141 gate driver family is suited to drive a single half bridge in power switching applications. The high gate driving capability (2A source, 3A sink) and the low quiescent current enable bootstrap supply techniques in medium power systems. These drivers feature full short circuit protection by means of the power transistor desaturation detection and manages all the half-bridge faults by turning off smoothly the desaturated transistor through the dedicated soft shut down pin, therefore preventing over-voltages and reducing EM emissions. In multi-phase system IR2114/21141/2214/IR22141 drivers communicate using a dedicated local network (SY_FLT and FAULT/SD signals) to properly manage phase-to-phase short circuits. The system controller may force shutdown or read device fault state through the 3.3 V compatible CMOS I/O pin (FAULT/SD). To improve the signal immunity from DC-bus noise, the control and power ground use dedicated pins enabling low-side emitter current sensing as well. Undervoltage conditions in floating and low voltage circuits are managed independently.
IR2214SS/IR22141SS
Product Summary
V
OFFSET
IO+/- (typ) 2.0 A / 3.0A
V
10.4V - 20V
OUT
Deadtime matching (max) 75 nsec
Deadtime (typ) 330 nsec
Desat blanking time (typ) 3 µsec
DSH, DSL input voltage
threshold (typ)
Soft shutdown time (typ) 9.25 µsec
Package
24-Lead SSOP
600V or
1200V max.
8.0 V
Typical connection
DC BUS
(1200V)
15 V
uP,
Control
VCC
LIN
HIN
FAULT/SD
FLT_CLR
SY_FLT
VSS
IR2214
HOP
HON
SSDH
DSH
LOP
LON
SSDL
COM
DC+
VB
DC-
Motor
VS
DSL
1
IR2114/IR21141/IR2214/IR22141
Absolute Maximum Ratings
Absolute maximum ratings indicate sustained limits beyond which damage to the device may occur. All voltage parameters are absolute voltages referenced to V The thermal resistance and power dissipation ratings are measured under board mounted and still air conditions.
Symbol Definition Min. Max. Units
VS High side offset voltage VB - 25 VB + 0.3 VB High side floating supply voltage
VHO High side floating output voltage (HOP, HON and SSDH) VS - 0.3 VB + 0.3 VCC Low side and logic fixed supply voltage -0.3 25
COM Power ground VCC - 25 VCC + 0.3
VLO Low side output voltage (LOP, LON and SSDL) VCOM -0.3 VCC + 0.3
VIN Logic input voltage (HIN, LIN and FLT_CLR) VSS -0.3 VCC + 0.3
VFLT FAULT input/output voltage (FAULT/SD and SY_FLT) VSS -0.3 VCC + 0.3 VDSH High side DS input voltage VS -3 VB + 0.3 VDSL Low side DS input voltage VCOM -3 VCC + 0.3
dVs/dt Allowable offset voltage slew rate 50 V/ns
PD Package power dissipation @ TA +25°C 1.5 W
RthJA Thermal resistance, junction to ambient 65 °C/W
TJ Junction temperature — 125 TS Storage temperature -55 150 TL Lead temperature (soldering, 10 seconds) 300
SS, all currents are defined positive into any lead
(IR2114 or IR21141)
(IR2214 or IR22141)
-0.3 625
-0.3 1225
V
°C
Recommended Operating Conditions
For proper operation the device should be used within the recommended conditions. All voltage parameters are absolute voltages referenced to V differential.
Symbol Definition Min. Max. Units
VB High side floating supply voltage (Note 1) VS + 11.5 VS + 20
VS High side floating supply offset
voltage
VHO High side output voltage (HOP, HON and SSDH) VS VS + 20 VLO Low side output voltage (LOP, LON and SSDL) VCOM VCC VCC Low side and logic fixed supply voltage (Note 1) 11.5 20
COM Power ground -5 5
VIN Logic input voltage (HIN, LIN and FLT_CLR) VSS VCC
VFLT Fault input/output voltage (FAULT/SD and SY_FLT) VSS VCC VDSH High side DS pin input voltage VS - 2.0 VB VDSL Low side DS pin input voltage VCOM - 2.0 VCC
TA Ambient temperature -40 125 °C
Note 1: While internal circuitry is operational below the indicated supply voltages, the UV lockout disables the output drivers if the UV thresholds are not reached. Note 2: Logic operational for V V
SS-VBS. (Please refer to the Design Tip DT97-3 for more details).
S from VSS-5V to VSS+600V or 1200V. Logic state held for VS from VSS-5V to
SS. The VS offset rating is tested with all supplies biased at 15V
(IR2114 or IR21141)
(IR2214 or IR22141)
Note 2 600 Note 2 1200
V
2
IR2114/IR21141/IR2214/IR22141
Static Electrical Characteristics
= 15 V, VSS = COM = 0 V, VS = 0 ÷ 600V or 1200 V and TA = 25 °C unless otherwise specified.
V
CC
Pin: V
Symbol Definition Min Typ Max Units Test Conditions
VCCUV+ Vcc supply undervoltage positive going threshold 9.3 10.2 11.4
VCCUV- Vcc supply undervoltage negative going threshold 8.7 9.3 10.3
VCCUVH Vcc supply undervoltage lockout hysteresis - 0.9 -
VBSUV+ (VB-VS) supply undervoltage positive going threshold 9.3 10.2 11.4 VS=0V, VS=600V
VBSUV- (VB-VS) supply undervoltage negative going
VBSUVH (VB-VS) supply undervoltage lockout hysteresis - 0.9 -
IQCC Quiescent Vcc supply current - 0.7 2.5
, VSS, VB, VS
CC
V
or 1200V
8.7 9.3 10.3 VS=0V, VS=600V
threshold
or 1200V
ILK Offset supply leakage current - - 50 VB = VS = 600V or
µA
IQBS Quiescent VBS supply current - 400 800
1200V
V
IN = 0V or 3.3V
mA (No load)
VCC/VB
comparator
internal
UV
signal
VCCUV/VBSUV
VSS/VS
Figure 1: Undervoltage diagram
Pin: HIN, LIN, FLTCLR, FAULT/SD, SY_FLT
Symbol Definition Min Typ Max Units Test Conditions
VIH Logic "1" input voltage 2.0 - ­VIL Logic "0" input voltage - - 0.8
VIHSS
IIN+ Logic "1" input bias current - 370 -
IIN- Logic "0" input bias current -1 - 0
RON,FLT FAULT/SD open drain resistance - 60 -
RON,SY SY_FLT open drain resistance - 60 -
Logic input hysteresis 0.2 0.4 -
CC = VCCUV- to
V
V
µA
20V
V
IN = 3.3V
V
IN = 0V
PW 7 µs
schmitt
HIN/LIN/ FLTCLR
VSS
trigger
10k
internal
signal
Figure 2: HIN, LIN and FLTCLR diagram
3
IR2114/IR21141/IR2214/IR22141
FAULT/SD
SY_FLT
VSS
RON
schmitt trigger
fault/hold
inte rnal signa l
hard/s oft shut down
inte rnal signa l
Figure 3: FAULT/SD and SY_FLT diagram
Pin: DSL, DSH
The active bias is present only in IR21141 and IR22141. V COM and V
Symbol Definition Min Typ Max Units Test Conditions
VDESAT+ High desat input threshold voltage 7.2 8.0 8.8
VDESAT- Low desat input threshold voltage 6.3 7.0 7.7
VDSTH Desat input voltage hysteresis - 1.0 -
IDS+ High DSH or DSL input bias current - 21 - VDESAT = VCC or VBS
IDS- Low DSH or DSL input bias current - -160 -
IDSB DSH or DSL input bias current - -20 - mA VDESAT =
(IR21141 and IR22141 only) (VCC or VBS) - 2V
respectively for DSL and DSH.
S
DESAT
, IDS and I
parameters are referenced to
DSB
V See Fig. 16, 4
µA
VDESAT = 0V
VCC/VBS
DSL/DSH
DESAT
V
COM/VS
active
100k
bias
comparator
700k
Figure 4: DSH and DSL diagram.
SSD
internal
signal
4
IR2114/IR21141/IR2214/IR22141
Pin: HOP, LOP
Symbol Definition Min Typ Max Units Test Conditions
VOH High level output voltage, VB – VHOP or Vcc –VLOP - 40 300
mV I
IO1+ Output high first stage short circuit pulsed current - 2 - VHOP/LOP=0V,
IO2+ Output high second stage short circuit pulsed current
- 1 -
A
200ns
oneshot
VCC/VB
O = 20mA
H
or LIN= 1,
IN
PW200ns,
resistive load,
see Fig. 8
VHOP/LOP=0V,
H
or LIN = 1,
IN
400nsPW10µs,
resistive load,
see Fig. 8
on/off
internal signal
VOH
LOP/HOP
Figure 5: HOP and LOP diagram
Pin: HON, LON, SSDH, SSDL
Symbol Definition Min Typ Max Units Test Conditions
VOL Low level output voltage, VHON or VLON - 45 300
RON,SSD Soft Shutdown on resistance (Note 1) - 90 -
IO- Output low short circuit pulsed current - 3 - A VHOP/LOP=15V,
mV I
O = 20mA
PW 7 µs
H
or LIN = 0,
IN
PW10µs
Note 1: SSD operation only.
LON/HON
on/off
internal signal
desat
internal signal
RON,SSD
SSDL/SSDH
VOL
COM/VS
Figure 6: HON, LON, SSDH and SSDL diagram
5
IR2114/IR21141/IR2214/IR22141
AC Electrical Characteristics
VCC = VBS = 15V, VS = VSS and TA = 25°C unless otherwise specified.
Symbol Definition Min. Typ. Max. Units Test Conditions
ton Turn on propagation delay 220 440 660 VIN = 0 & 1 toff Turn off propagation delay 220 440 660 VS = 0 to 600V or
1200V
tr Turn on rise time (C
tf Turn off fall time (C
ton1 Turn on first stage duration time 120 200 280 Figure 8
tDESAT1 DSH to HO soft shutdown propagation delay at HO 2000 3300 4600
turn on VHIN= 1
tDESAT2 DSH to HO soft shutdown propagation delay after 1050 — VDESAT = 15V,Fig.10
Blanking
tDESAT3 DSL to LO soft shutdown propagation delay at LO 2000 3300 4600
turn on VLIN = 1
tDESAT4 DSL to LO soft shutdown propagation delay after 1050 — VDESAT = 15V,Fig.10
Blanking
tDS Soft shutdown minimum pulse width of desat 1000 — Figure 9
tSS Soft shutdown duration period 5000 9250 13500
VDS=15V,Fig. 9
=1nF) — 24 HOP shorted to HON,
LOAD
=1nF) — 7 Figure 7
LOAD
LOP shorted to LON,
ns
tSY_FLT, DSH to SY_FLT propagation delay at HO turn on — 3600
DESAT1
tSY_FLT, DSH to SY_FLT propagation delay after blanking 1300 — VDS = 15V, Fig. 10
DESAT2
tSY_FLT, DSL to SY_FLT propagation delay at LO turn on — 3050
DESAT3
tSY_FLT, DSL to SY_FLT propagation delay after blanking 1050 — VDESAT=15V,Fig.10
DESAT4
tBL DS blanking time at turn on — 3000 VHIN = VLIN = 1
VDESAT=15V,Fig.10
Dead-time/Delay Matching Characteristics
DT Dead-time 330 Figure 11
MDT Dead-time matching, MDT=DTH-DTL 75 External DT=0nsec
Figure 11
PDM Propagation delay matching, 75 External DT>
Max(ton, toff) - Min(ton, toff)
VHIN = 1
VLIN = 1
500nsec, Fig.7
6
HIN LIN
IR2114/IR21141/IR2214/IR22141
3.3V
t
on
50%
t
r
PW
in
PW
out
50%
t
off
t
f
HO (HOP=HON) LO (LOP=LON)
90%
90%
10%
10%
Figure 7: Switching Time Waveforms
Ton1
Io1+
Io2+
Figure 8: Output Source Current
3.3V
HIN/LIN
t
DS
DSH/DSL
SSD Driver Enable
8V
t
DESAT
8V
t
SS
HO/LO
Figure 9: Soft Shutdown Timing Waveform
7
IR2114/IR21141/IR2214/IR22141
(
(
HIN
50%
50%
LIN
DSH
DSL
SY_FLT
FAULT/SD
FLTCLR
10%
HON
LON
8V
50%
LIN HIN
50%
SY_FLT,DESAT1
t
tDESAT1
90%
tBL
Turn-On Propaga tion Delay
8V
50%
tSY_FLT,DESAT2
tDESAT2
90%
SoftShutdown
50%
tBL
SoftShutdown
Figure 10: Desat Timing
50% 50%
10%
50%
8V
50%
SY_FLT,DESAT3
t
t
DESAT3
tBL
Turn-On Propaga tion Delay
50%
90%
SoftShutdown
tSY_FLT,DESAT4
50%
8V
50%
Turn_Off propaga tion Delay
90%
t
DESAT4
90%
SoftShutdown
tBL
90%
HOP=HON)
HO
LOP=LON)
LO
50%
DTH
50%
50%
DTL
50%
MDT=DTH-DTL
Figure 11: Internal Dead-Time Timing
8
IR2114/IR21141/IR2214/IR22141
Lead Assignments
HIN
LIN
FLT_CLR
SY_FLT
24-Lead SSOP
Lead Definitions
Symbol Description
FAULT/SD
VSS
SSDL
COM
LON
LOP
VCC
DSL
1
SSOP24
12
24
13
DSH
VB
N.C.
HOP
HON
VS
SSDH
N.C.
N.C.
N.C.
N.C.
N.C.
VCC Low side gate driver supply VSS Logic Ground
HIN Logic input for high side gate driver outputs (HOP/HON)
LIN Logic input for low side gate driver outputs (LOP/LON)
FAULT/SD
SY_FLT
FLT_CLR Fault clear active high input. Clears latched fault condition (See figure 17)
LOP Low side driver sourcing output LON Low side driver sinking output DSL Low side IGBT desaturation protection input
SSDL Low side soft shutdown
COM Low side driver return
VB High side gate driver floating supply HOP High side driver sourcing output HON High side driver sinking output
DSH High side IGBT desaturation protection input
SSDH High side soft shutdown
VS High side floating supply return
Dual function (in/out) active low pin. Refer to figures 17, 18 and 15. As an output, indicates fault condition. As an input, shuts down the outputs of the gate driver regardless H
Dual function (in/out) active low pin. Refer to figures 17, 18 and 15. As an output, indicates SSD sequence is occurring. As an input, an active low signal freezes both output status.
IN/LIN
status.
9
Functional Block Diagram
IR2114/IR21141/IR2214/IR22141
VCC
HIN
LIN
UV_VCC DETECT
SY_FLT
FAULT/SD
FAULT
FLT_CLR
VSS
State Diagram
SCHMITT
TRIGGER
INPUT
SHOOT
THROUGH
PREVENTION
(DT) Deadtime
UV_VCC
HOLDSSD
SD
INPUT HOLD LOGIC
internal Hold
FAULT LOGIC
managemend
(See figure 14)
Start-Up
Sequence
OUTPUT
SHUTDOWN
LOGIC
Hard ShutDown
on/off (HS)
on/off (LS)
DesatHS
DesatLS
LEVEL
SHIFTERS
on/off
desat
LATCH
LOCAL DESAT PROTECTION
SOFT SHUTDOW N
UV_VBS DETECT
LOCAL DESAT PROTECTION
SOFTSHUTDOW N
on/off
soft
shutdown
on/off
soft
shutdown
di/dt control Driver
di/dt control Driver
VB
HOP
HON
SSDH
DSH
VS
LOP
LON
SSDL
DSL
COM
T
L
F
_
Y
FAULT
ShutDown
S
HO=LO=0
N
I
L
/
N
R
L
C
_
T
L
F
DESAT EVENT
Soft
I
H
L
/
N
I
H
HO/LO=1
L
S
/
H
Y
S
_
D
F
L
T
N
I
F
A
_
V
U
UV_VBS
U
L
T
/
S
F
A
U
C C
V _
V
U
UnderVoltage
V
CC
HO=LO=0
C
C
V
D
L
T
/
S
D
UV_VCC
F
A
U
V
_
V
B
S
UnderVoltage
V
BS
HO=0, LO=LIN
U
L
T
/
S
D
ShutDown
D
S
/
T
L
U
A
F
S
Y
_
F
L
T
D
S
/
T
L
U
A
F
Freeze
L
/
H
S
D
Stable State
FAULT
HO=LO=0 (Normal operation)
HO/LO=1 (Normal operation)
UNDERVOLTAGE V
SHUTDOWN (SD)
UNDERVOLTAGE V
FREEZE
CC
BS
Temporary State
SOFT SHUTDOWN
START UP SEQUENCE
System Variable
FLT_CLR
HIN/LIN
UV_VCC
UV_VBS
DSH/L
SY_FLT
FAULT/SD
NOTE1: a change of logic value of the signal labeled on lines (system variable) generates a state transition. NOTE2: Exiting from UNDERVOLTAGE V
.
H
IN
state, the HO goes high only if a rising edge event happens in
BS
10
IR2114/IR21141/IR2214/IR22141
Logic Table
Output drivers status description
HO/LO
status
0 HiZ 0 HiZ 1 1 HiZ HiZ
SSD HiZ HiZ 0
LO/HO
LO
/HO
n-1
Operation
Shut Down
Fault Clear
Normal
Operation
Anti Shoot
Through
Soft Shut
Down
(entering)
Soft Shut
Down
(finishing)
Freeze
Under
Voltage
NOTE1: SY_FLT automatically resets after SSD event is over and FLT_CLR is not required. In order to avoid FLT_CLR to conflict with the SSD procedure, FLT_CLR should not be operated while SY_FLT is active.
HOP/LOP HON/LON SSDH/SSDL
Output follows inputs (in=1->out=1, in=0->out=0)
n-1
Output keeps previous status
INPUTS
Lin
FLT_CLR
Hin
INPUT/OUTPUT
SY_FLT
SSD: desat (out) HOLD: freezing (in)
FAULT/SD
SD: shutdown (in) FAULT: diagnostic (out)
Under Voltage
Yes: V< UV threshold No : V> UV threshold X : don’t care
V
VBS HO LO
CC
OUTPUTS
X X X X 0 (SD) X X 0 0
(FAULT)
H
LIN
IN
NOTE1
No No HO
LO
1 0 0 1 1 No No 1 0
0 1 0 1 1 No No 0 1
0 0 0 1 1 No No 0 0
1 1 0 1 1 No No 0 0
1 0 0
0 1 0
X X 0
X X 0
(SSD)
(SSD)
(SSD) (FAULT)
(SSD) (FAULT)
X X X 0 (HOLD) 1 No No HO
X L
X 1 1 No Yes 0 LO
IN
1 No No SSD 0
1 No No 0 SSD
No No 0 0
No No 0 0
LO
n-1
X X X 1 0 (FAULT) Yes X 0 0
n-1
11
IR2114/IR21141/IR2214/IR22141
FEATURES DESCRIPTION
1 Start-up sequence
At power supply start-up it is recommended to keep FLT_CLR pin active until supply voltages are properly established. This prevents spurious diagnostic signals being generated. All protection functions are operating independently from FLT_CLR status and output driver status reflects the input commands. When bootstrap supply topology is used for supplying the floating high side stage, the following start-up sequence is recommended (see also figure 12):
1. Set Vcc
2. Set FLT_CLR pin to HIGH level
3. Set LIN pin to HIGH level and let the bootstrap capacitor be charged
4. Release LIN pin to LOW level
5. Release FLT_CLR pin to LOW level
VCC
FLT_CLR
LIN
LO
Figure 12 Start-up sequence A minimum 15 us LIN and FLT-CLR pulse is required.
2 Normal operation mode
After start-up sequence has been terminated, the device becomes fully operative (see grey blocks in the State Diagram). HIN and LIN produce driver outputs to switch accordingly, while the input logic checks the input signals preventing shoot-through events and including DeadTime (DT).
3 Shut down
The system controller can asynchronously command the Hard ShutDown (HSD) through the
3.3 V compatible CMOS I/O FAULT/SD pin. This event is not latched. In a multi-phase system, FAULT/SD signals are or­wired so the controller or one of the gate drivers can force simultaneous shutdown to the other gate drivers through the same pin.
4 Fault management
IR2114/21141/2214/22141 is able to manage the both the supply failure (undervoltage lock out on
both low and high side circuits) and the desaturation of both power transistors.
4.1 Undervoltage (UV)
The Undervoltage protection function disables the driver’s output stage preventing the power device being driven with too low voltages. Both the low side (V side (V
supplied) are controlled by a dedicate
BS
supplied) and the floating
CC
undervoltage function. Undervoltage event on the V V
< UV
CC
) generates a diagnostic signal by
VCC-
(when
CC
forcing FAULT/SD pin low (see FAULT/SD section and figure 14). This event disables both low side and floating drivers and the diagnostic signal holds until the under voltage condition is over. Fault condition is not latched and the FAULT/SD pin is released once V The undervoltage on the V the floating driver. Undervoltage on V
becomes higher than UV
CC
works disabling only
BS
VCC+
does not
BS
.
prevent the low side driver to activate its output nor generate diagnostic signals. V condition (V
< UV
BS
) latches the high side
VBS-
output stage in the low state. V reestablished higher than UV
undervoltage
BS
must be
BS
to return in
VBS+
normal operating mode. To turn on the floating driver H event on H
must be re-asserted high (rising edge
IN
is required).
IN
4.2 Power devices desaturation
Different causes can generate a power inverter failure: phase and/or rail supply short-circuit, overload conditions induced by the load, etc… In all these fault conditions a large current increase is produced in the IGBT. The IR2114/21141/2214/22141 fault detection circuit monitors the IGBT emitter to collector voltage (V diode. High current in the IGBT may cause the transistor to desaturate, i.e. V Once in desaturation, the current in power transistor can be as high as 10 times the nominal current. Whenever the transistor is switched off, this high current generates relevant voltage transients in the power stage that need to be smoothed out in order to avoid destruction (by over-voltages). The gate driver accomplishes the transients control by smoothly turning off the desaturated transistor by means of the SSD pin activating a so called Soft ShutDown sequence (SSD).
4.2.1 Desaturation detection: DSH/L function
Figure 13 shows the structure of the desaturation sensing and soft shutdown block. This configuration is the same for both high and low side output stages.
) by means of an external high voltage
CE
to increase.
CE
12
IR2114/IR21141/IR2214/IR22141
on/off
DesatHS/LS
SY_FLT
(external
hold)
tss
One Shot
VB/Vcc
PPrreeDDrriivveer
tBL
Blanking
r
ONE SHOT (ton1)
HOPH/L
HONH/L
SSDH/L
Ron,ss
RDSH/L
DSH/L
filter
tDS
desat
comparator
VDESAT
VS/COM
Figure 13: high and low side output stage
internal
HOLD
internal FAULT
(hard shutdown)
sensing
diode
FAULT/SD
(external hard
shutdown)
FLTCLR
Figure 14: fault management diagram
The external sensing diode should have BV>600V or 1200V and low stray capacitance (in order to minimize noise coupling and switching delays). The diode is biased by an internal pull-up resistor
(equal to VCC/I
R
DSH/L
or VBS/I
DS-
for IR2114 or
DS-
IR2214) or by a dedicated circuit (see the active­bias section for IR21141 and IR22141). When V
CE
increases, the voltage at DSH/L pin increases too. Being internally biased to the local supply, DSH/L voltage is automatically clamped. When DSH/L exceeds the V
threshold the comparator
DESAT+
triggers (see figure 13). Comparator output is filtered in order to avoid false desaturation detection by externally induced noise; pulses shorter than t
are filtered out. To avoid detecting
DS
a false desaturation during IGBT turn on, the desaturation circuit is disabled by a Blanking signal (T
, see Blanking block in figure 13). This time is
BL
the estimated maximum IGBT turn on time and must be not exceeded by proper gate resistance sizing. When the IGBT is not completely saturated
SET
S
Q
R
Q
CLR
DesatHS
DesatLS
UVCC
after T
, desaturation is detected and the driver
BL
will turn off. Eligible desaturation signals initiate the Soft Shutdown sequence (SSD). While in SSD, the output driver goes in high impedance and the SSD pull-down is activated to turn off the IGBT through SSDH/L pin. The SY_FLT output pin (active low, see figure 14) reports the gate driver status all the way long SSD sequence lasts (t
). Once finished
SS
SSD, SYS_FLT releases, and the gate driver generates a FAULT signal (see the FAULT/SD section) by activating FAULT/SD pin. This generates a hard shut down for both high and low output stages (HO=LO=low). Each driver is latched low until the fault is cleared (see FLT_CLR). Figure 14 shows the fault management circuit. In this diagram DesatHS and DesatLS are two internal signals that come from the output stages (see figure 13). It must be noted that while in Soft Shut Down, both Under Voltage fault and external Shut Down (SD)
13
IR2114/IR21141/IR2214/IR22141
are masked until the end of SSD. Desaturation protection is working independently by the other entire control pin and it is disabled only when the output status is off.
FAULT
SY_FLT
FAULT/SD
VCC
LIN
HIN
FLT_CLR
VB
HOP
HON
SSH
DSH
VS
LOP
IR2214
LON
SSL
DSL
COMVSS
phase U phase V phase W
SY_FLT
FAULT/SD
VCC
LIN
HIN
FLT_CLR
IR2214
VB
HOP
HON
SSH
DSH
VS
LOP
LON
SSL
DSL
COMVSS
SY_FLT
FAULT/SD
VCC
LIN
HIN
FLT_CLR
IR2214
VB
HOP
HON
SSH
DSH
VS
LOP
LON
SSL
DSL
COMVSS
Figure 15: IR2x14x application in 3ph system.
4.2.2 Fault management in multi-phase systems
In a system with two or more gate drivers the devices must be connected as in figure 15.
SY_FLT. The bi-directional SY_FLT pins communicate each other in the local network. The logic signal is active low. The device that detects the IGBT desaturation activates the SY_FLT, which is then read by the other gate drivers. When SYS_FLT is active all the drivers hold their output state regardless the input signals (H
, LIN) they receive from the controller
IN
(freeze state). This feature is particularly important in phase-to­phase short circuit where two IGBTs are involved; in fact, while one is softly shutting-down, the other must be prevented from hard shutdown to avoid vanishing SSD. In the Freeze state the frozen drivers are not completely inactive because desaturation detection still takes the highest priority. SY_FLT communication has been designed for creating a local network between the drivers. There is no need to wire SY_FLT to the controller.
FAULT/SD The bi-directional FAULT/SD pins communicates each other and with the system controller. The logic signal is active low. When low, the FAULT/SD signal commands the outputs to go off by hard shutdown. There are three events that can force FAULT/SD low:
1. Desaturation detection event: the FAULT\SD pin is latched low when SSD is over, and only a FLT_CLR signal can reset it.
2. Undervoltage on V
: the FAULT\SD pin is
CC
forced low and held until the undervoltage is active (not latched).
3. FAULT/SD is externally driven low either from the controller or from another IR2x14x device. This event is not latched; therefore the FLT_CLR cannot disable it. Only when FAULT/SD becomes high the device returns in normal operating mode.
5 Active bias
For the purpose of sensing the power transistor desaturation the collector voltage is read by an external HV diode. The diode is normally biased by an internal pull up resistor connected to the local supply line (V the diode is conducting and the amount of current flowing in the circuit is determined by the internal pull up resistor value. In the high side circuit, the desaturation biasing current may become relevant for dimensioning the bootstrap capacitor (see figure 19). In fact, too low pull up resistor value may result in high current discharging significantly the bootstrap capacitor. For that reason typical pull up resistor are in the range of 100 k. This is the value of the internal pull up. While the impedance of DSH/DSL pins is very low when the transistor is on (low impedance path through the external diode down to the power transistor), the impedance is only controlled by the pull up resistor when the transistor is off. In that case relevant dV/dt applied by the power transistor during the commutation at the output results in a considerable current injected through the stray capacitance of the diode into the desaturation detection pin (DSH/L). This coupled noise may be easily reduced using an active bias for the sensing diode. An Active Bias structure is available only for IR21141 or IR22141 version for DSH/L pin. The DSH/L pins present an active pull-up respectively to VB/VCC, and a pull-down respectively to VS/COM. The dedicated biasing circuit reduces the impedance on the DSH/L pin when the voltage exceeds the V low impedance helps in rejecting the noise providing the current inject by the parasitic capacitance. When the power transistor is fully on, the sensing diode gets forward biased and the voltage at the DSH/L pin decreases. At this point the biasing circuit deactivates, in order to reduce the bias current of the diode as shown in figure 16.
or VCC). When the transistor is “on”
B
threshold (see figure 16). This
DESAT
DSH/L
R
100K ohm
100 ohm
VDSH/L
Figure 16: R
-
+
T
T
A
A
S
S
E
E
D
D
V
V
Active Biasing
DSH/L
14
IR2114/IR21141/IR2214/IR22141
6 Output stage
The structure is shown in figure 13 and consists of two turns on stages and one turn off stage. When the driver turns on the IGBT (see figure 8), a first stage is constantly activated while an additional stage is maintained active only for a limited time (ton1). This feature boost the total driving capability in order to accommodate both fast gate charge to the plateau voltage and dV/dt control in switching.
A B C D E F G
HIN
LIN
DSH
DSL
SY_FLT
FAULT/SD
At turn off, a single n-channel sinks up to 3A (I and offers a low impedance path to prevent the self-turn on due to the parasitic Miller capacitance in the power switch.
7 Timing and logic state diagrams description
The following figures show the input/output logic diagram. Figure 17 shows the SY_FLT and FAULT/SD signals as output, whereas figure 18 as input.
)
O-
FLT_CLR
HO(HOP/HON)
LO(LOP/LON)
Figure 17: I/O timing diagram with SY_FLT and FAULT/SD as output
HIN
LIN
SY_FLT
FAULT/SD
FLT_CLR
HO (HOP/HON)
LO (LOP/LON)
Figure 18: I/O logic diagram with SY_FLT and FAULT/SD as input
Referred to timing diagram of figure 17:
A. When the input signals are on together
the outputs go off (anti-shoot through).
B. The HO signal is on and the high side
IGBT desaturates, the HO turn off softly while the SY_FLT stays low. When
ABCD EF
SY_FLT goes high the FAULT/SD goes low. While in SSD, if LIN goes up, LO does not change (freeze).
C. When FAULT/SD is latched low (see
FAULT/SD section) FLT_CLR can disable
15
IR2114/IR21141/IR2214/IR22141
−≤∆
++=
it and the outputs go back to follow the inputs.
D. The DSH goes high but this is not read
because HO is off.
E. The LO signal is on and the low side
IGBT desaturates, the low side behaviour is the same as described in point B.
F. The DSL goes high but this is not read
because LO is off.
G. As point A (anti-shoot through).
Referred to timing diagram figure 18:
A. The device is in hold state, regardless of
input variations. Hold state is forced by SY_FLT forced low externally
B. The device outputs goes off by hard
shutdown, externally commanded. A through B is the same sequence adopted by another IR2x14x device in SSD procedure.
C. Externally driven low FAULT/SD
(shutdown state) cannot be disabled by forcing FLT_CLR (see FAULT/SD section).
D. The FAULT/SD is released and the
outputs go back to follow the inputs.
E. Externally driven low FAULT/SD: outputs
go off by hard shutdown (like point B).
F. As point A and B but for the low side
output.
Sizing tips
Bootstrap supply
The V side driver circuitry of the gate driver. This supply sits on top of the V floating. The bootstrap method to generate V be used with any of the IR2114, IR21141, IR2214, IR22141. The bootstrap supply is formed by a diode and a capacitor connected as in figure
19.
VCC
voltage provides the supply to the high
BS
voltage and so it must be
S
resistor
R
bootstrap
diode
boot
VF
VB
HOP
HON
VS
IR2214
SSDH
bootstrap
VBS
capacitor
bootstrap
VCC
Figure 19: bootstrap supply schematic
supply can
BS
DC+
VGE
VCEon
COM
ILOAD
motor
VFP
This method has the advantage of being simple and low cost but may force some limitations on duty-cycle and on-time since they are limited by the requirement to refresh the charge in the bootstrap capacitor. Proper capacitor choice can reduce drastically these limitations.
Bootstrap capacitor sizing
To size the bootstrap capacitor, the first step is to establish the minimum voltage drop (V we have to guarantee when the high side IGBT is on. If V
is the minimum gate emitter voltage we
GEmin
want to maintain, the voltage drop must be:
VVVVV
min
under the condition:
>
BSUVGEVVmin
where V diode forward voltage, V voltage of low side IGBT and V
is the IC voltage supply, VF is bootstrap
CC
is emitter-collector
CEon
BSUV-
side supply undervoltage negative going threshold.
Now we must consider the influencing factors contributing V
to decrease:
BS
IGBT turn on required Gate charge (Q
IGBT gate-source leakage current (I
Floating section quiescent current (I
Floating section leakage current (I
Bootstrap diode leakage current (I
Desat diode bias when on (I
DS-
)
Charge required by the internal level shifters
(Q
); typical 20nC
LS
Bootstrap capacitor leakage current
(I
);
LK_CAP
High side on time (T
I
is only relevant when using an electrolytic
LK_CAP
HON
).
capacitor and can be ignored if other types of capacitors are used. It is strongly recommend using at least one low ESR ceramic capacitor (paralleling electrolytic and low ESR ceramic may result in an efficient solution).
Then we have:
++
(
The minimum size of bootstrap capacitor is:
IIQQQ
QBSGELKLSGTOT
_
__
) that
BS
CEonGEFCCBS
is the high-
);
G
);
LK_GE
);
QBS
)
LK
LK_DIODE
);
TIIII ++++
)
HONDSCAPLKDIODELKLK
16
IR2114/IR21141/IR2214/IR22141
=
=
=
Q
TOT
C
BOOT
min
=
V
BS
An example follows using IR2214SS or IR22141SS:
a) using a 25A @ 125C 1200V IGBT (IRGP30B120KD):
I
= 800 µA (This Datasheet);
QBS
= 50 µA (See Static Electrical Charact.);
I
LK
= 20 nC;
Q
LS
= 160 nC (Datasheet IRGP30B120KD);
Q
G
I
I
= 100 nA (Datasheet IRGP30B120KD);
LK_GE
= 100 µA (with reverse recovery time
LK_DIODE
<100 ns);
I
I
T
= 0 (neglected for ceramic capacitor);
LK_CAP
= 150 µA (see Static Electrical Charact.);
DS-
= 100 µs.
HON
And:
V
V
V
V
= 15 V
CC
= 1 V
F
CEonmax
= 10.5 V
GEmin
= 3.1 V
the maximum voltage drop V
becomes
BS
min
VVVVV
CEonGEFCCBS
=
VVVVV 4.01.35.10115
=
And the bootstrap capacitor is:
C
BOOT
290
V
4.0
=
725
nF
nC
NOTICE: Here above V
has been chosen
CC
to be 15V. Some IGBTs may require higher supply to work correctly with the bootstrap technique. Also Vcc variations must be accounted in the above formulas.
Some important considerations
a. Voltage ripple There are three different cases making the bootstrap circuit gets conductive (see figure 19)
I
< 0; the load current flows in the low
LOAD
side IGBT displaying relevant V
In this case we have the lowest value for V This represents the worst case for the bootstrap capacitor sizing. When the IGBT is turned off
CEon
VVVV =
CEonFCCBS
.
BS
the Vs node is pushed up by the load current until the high side freewheeling diode get
forwarded biased I on and V
= 0; the IGBT is not loaded while being
LOAD
can be neglected
CE
VVV
FCCBS
I
> 0; the load current flows through the
LOAD
freewheeling diode
VVVV +
FPFCCBS
In this case we have the highest value for V
Turning on the high side IGBT, I
and V
is pulled up.
S
flows into it
LOAD
BS
.
To minimize the risk of undervoltage, bootstrap capacitor should be sized according to the I
LOAD
<0
case.
b. Bootstrap Resistor A resistor (R
boot
) is placed in series with bootstrap diode (see figure 19) so to limit the current when the bootstrap capacitor is initially charged. We suggest not exceeding some Ohms (typically 5, maximum 10 Ohm) to avoid increasing the V
BS
time-constant. The minimum on time for charging the bootstrap capacitor or for refreshing its charge must be verified against this time-constant.
c. Bootstrap Capacitor For high T
designs where is used an
HON
electrolytic tank capacitor, its ESR must be considered. This parasitic resistance forms a voltage divider with R on V
at the first charge of bootstrap capacitor.
BS
The voltage step and the related speed (dV
generating a voltage step
boot
BS
/dt) should be limited. As a general rule, ESR should meet the following constraint:
ESR
+
RESR
BOOT
CC
VV
3
Parallel combination of small ceramic and large electrolytic capacitors is normally the best compromise, the first acting as fast charge thank for the gate charge only and limiting the dV
BS
/dt by reducing the equivalent resistance while the second keeps the V desired V
BS
.
voltage drop inside the
BS
d. Bootstrap Diode The diode must have a BV> 600V or 1200V and a fast recovery time (trr < 100 ns) to minimize the amount of charge fed back from the bootstrap capacitor to V
supply.
CC
17
IR2114/IR21141/IR2214/IR22141
+
=
t
Gate resistances
The switching speed of the output transistor can be controlled by properly size the resistors controlling the turn-on and turn-off gate current. The following section provides some basic rules for sizing the resistors to obtain the desired switching time and speed by introducing the equivalent output resistance of the gate driver (R
DRp
and R
DRn
). The examples always use IGBT power transistor. Figure 20 shows the nomenclature used in the following paragraphs. In addition, V the plateau voltage, Q
and Q
gc
ge
*
indicates
ge
indicate the gate to collector and gate to emitter charge respectively.
I
C
GC
VGE
I
C
C
C
t,Q
RESon
RESoff
Vge*
C
RES
VGE
t1,Q
GE
V
CE
90%
t2,Q
dV/dt
C
RES
10%
10%
t
SW
t
Don
t
R
Figure 20: Nomenclature
Sizing the turn-on gate resistor
-
Switching-time
For the matters of the calculation included hereafter, the switching time t time spent to reach the end of the plateau voltage (a total Q
has been provided to the IGBT
gc+Qge
gate). To obtain the desired switching time the gate resistance can be sized starting from Q
, Vcc, V
Q
gc
*
(see figure 21):
ge
QQI+
gegc
avg
=
t
sw
and
*
VVcc
ge
=
R
TOT
I
avg
is defined as the
sw
ge
and
I
Vcc/Vb
R
DRp
R
COM/Vs
Figure 21: R
where
= gate on-resistor
R
Gon
R
= driver equivalent on-resistance
DRp
When R
> 7 Ohm, R
Gon
Vcc
 
I
=
R
DRp
  
Vcc
I
oo
Vcc
I
 
++
o
+
1
(I
,I
O1+
and t
O2+
on1
Characteristics”).
Table 1 reports the gate resistance size for two commonly used IGBTs (calculation made using typical datasheet values and assuming Vcc=15V).
- Output voltage slope
Turn-on gate resistor R output slope While the output voltage has a non-linear behaviour, the maximum output slope can be approximated by:
dV
out
dt
inserting the expression yielding I rearranging:
R
TOT
As an example, table 2 shows the sizing of gate resistance to get dV popular IGBTs, typical datasheet values and assuming Vcc=15V.
(dV
I
avg
=
C
RESoff
=
C
RESoff
/dt).
OUT
*
VVcc
ge
dV
out
d
out
avg
C
RES
Gon
sizing
Gon
RRR
GonDRpTOT
is defined by
DRp
t
SW
+
1
t
on
121
>
ttwhen
onSW
ttwhen
onSW
from “static Electrical
can be sized to control
Gon
and
avg
/dt=5V/ns when using two
1
1
18
IR2114/IR21141/IR2214/IR22141
(
NOTICE: Turn on time must be lower than TBL to avoid improper desaturation detection and SSD triggering.
Sizing the turn-off gate resistor
The worst case in sizing the turn-off resistor R is when the collector of the IGBT in off state is
Goff
As a result, when τ is faster than the collector rise time (to be verified after calculation) the transfer function can be approximated by:
V
ge
V
de
forced to commutate by external events (i.e. the turn-on of the companion IGBT). In this case the dV/dt of the output node induces a parasitic current through C and R
(see figure 22).
DRn
flowing in R
RESoff
Goff
So that
time domain. Then the condition:
If the voltage drop at the gate exceeds the threshold voltage of the IGBT, the device may self turn on causing large oscillation and relevant cross conduction.
must be verified to avoid spurious turn on.
Rearranging the equation yields:
dV/dt
V
C
RESoff
th
R
<
Goff
In any case, the worst condition for unwanted turn on is with very fast steps on IGBT collector. In that case collector to gate transfer function can
ON
HS Turning ON
R
Goff
R
DRn C
C
RESoff
OFF
IES
be approximated with the capacitor divider:
Figure 22: R
sizing: current path when Low
Goff
Side is off and High Side turns on
The transfer function between IGBT collector and IGBT gate then becomes:
)(
V
ge
=
V
de
CRRs
+
RESoffDRnGoff
+++
)()(1
CCRRs
IESRESoffDRnGoff
Which yields to a high pass filter with a pole at:
/1
=
τ
1
)()(
CCRR ++
IESRESoffDRnGoff
VV
dege
which is driven only by IGBT characteristics.
As an example, table 3 reports R with the above mentioned disequation) for two popular IGBTs to withstand dV
NOTICE: the above-described equations are intended being an approximated way for the gate resistances sizing. More accurate sizing may account more precise device modelling and parasitic component dependent on the PCB and power section layout and related connections.
C
=
Table 1: tsw driven R
IGBT Qge Qgc Vge* tsw Iavg Rtot
IRGP30B120K(D) 19nC 82nC 9V 400ns 0.25A IRG4PH30K(D) 10nC 20nC 9V 200ns 0.15A
Table 2: dV
IGBT Qge Qgc Vge* CRESoff Rtot
IRGP30B120K(D) 19nC 82nC 9V 85pF IRG4PH30K(D) 10nc 20nC 9V 14pF
Table 3: R
IGBT Vth(min) CRESoff RGoff
IRGP30B120K(D) 4 85pF RGoff  4  IRG4PH30K(D) 3 14pF RGoff  35 
/dt driven R
OUT
sizing
Goff
sizing
Gon
sizing
Gon
RGon
std commercial value
24
RTOT - RDRp = 12.7 10 420ns
40
RTOT - RDRp = 32.5 → 33 →202ns
std commercial value
RGon
14
RTOT - RDRp = 6.5 8.2 4.5V/ns
85
RTOT - RDRp = 78 82 5V/ns
dV
dt
RESoff
CRRs
+= )(
)
R
DRn
CC
+
IESRESoff
RESoffDRnGoff
CRRV
CRRVV
+=>
RESoffDRnGoffgeth
+= )( in the
RESoffDRnGoffge
dV
out
dt
dV
)(
(calculated
Goff
/dt = 5V/ns.
out
dVout/dt
de
dt
Tsw
19
PCB LAYOUT TIPS
Distance from H to L voltage:
The IR2x14x pin out maximizes the distance between floating (from DC- to DC+) and low voltage pins. It’s strongly recommended to place components tied to floating voltage in the high voltage side of device (V components in the opposite side.
Ground plane:
Ground plane must not be placed under or nearby the high voltage floating side to minimize noise coupling.
Gate drive loops:
Current loops behave like an antenna able to receive and transmit EM noise. In order to reduce EM coupling and improve the power switch turn on/off performances, gate drive loops must be reduced as much as possible. Figure 23 shows the high and low side gate loops. Moreover, current can be injected inside the gate drive loop via the IGBT collector-to-gate parasitic capacitance. The parasitic auto-inductance of the gate loop contributes to develop a voltage across the gate-emitter increasing the possibility of self turn-on effect. For this reason is strongly recommended to place the three gate resistances close together and to minimize the loop area (see figure 23).
VB/ VCC
H/LOP H/LON
SSDH/L
gate
resistance
, VS side) while the other
B
IGC
CGC
Gate Drive
Loop
VGE
IR2114/IR21141/IR2214/IR22141
Routing and placement example:
Figure 24 shows one of the possible layout solutions using a 3 layer PCB. This example takes into account all the previous considerations. Placement and routing for supply capacitors and gate resistances in the high and low voltage side minimize respectively supply path and gate drive loop. The bootstrap diode is placed under the device to have the cathode as close as possible to bootstrap capacitor and the anode far from high voltage and close to V
V
V
V
V
R2
GH
R3
R4
R5
GL
R6
R7
EH
V
CC
EL
.
CC
D2
DC+
IR2214
D3
Phase
C2
a)
C1
D1
R1
b)
VS/COM
Figure 23: gate drive loop
Supply capacitors:
IR2x14x output stages are able to quickly turn on IGBT with up to 2 A of output current. The supply capacitors must be placed as close as possible to the device pins (V supply, V
and VS for the floating supply) in order
B
to minimize parasitic inductance/resistance.
and VSS for the ground tied
CC
c)
Figure 24: layout example: top (a), bottom (b) and
ground plane (c) layer
Referred to figure 24: Bootstrap section: R1, C1, D1 High side gate: R2, R3, R4 High side Desat: D2 Low side supply: C2 Low side gate: R5, R6, R7 Low side Desat: D3
20
Case Outline
IR2114/IR21141/IR2214/IR22141
IR WORLD HEADQUARTERS:
233 Kansas St., El Segundo, California 90245 Tel: (310) 252-7105
This product has been designed and qualified for industrial market
Data and specifications subject to change without notice. 3/24/2005
21
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