ON NCP1366BABAYDR2G Low power offline constant current pwm current-mode controller Datasheet

NCP1361, NCP1366
Low Power Offline Constant
Current PWM Current-Mode
Controller with/without
High Voltage Startup
Current Source
The NCP1361/66 offers a new solution targeting output power
levels from a few watts up to 20 W in a universal−mains flyback
application. Due to a novel method this new controller offers a
primary−side constant current control, saving secondary−side
components to perform current regulation.
The NCP1361/66 operates in valley−lockout quasi−resonant peak
current mode control mode at nominal load to provide high efficiency.
When the secondary−side power starts diminishing, the switching
frequency naturally increases until a voltage−controlled oscillator
(VCO) takes the lead, synchronizing the MOSFET turn−on in a
drain−source voltage valley. The frequency is thus reduced by
stepping into successive valleys until the number 4 is reached. Beyond
this point, the frequency is linearly decreased in valley−switching
mode until a minimum is hit. Valley lockout during the first four
drain−source valleys prevents erratic discrete jumps and provides
good efficiency in lighter load situations.
• ±10% Current Regulation
• 560 V Startup Current Source
• No Frequency Clamp, 80 or 110 kHz Maximum Switching
Frequency Options
• Quasi−Resonant Operation with Valley Switching
•
•
•
•
•
•
October, 2015 − Rev. 1
8
SOIC−7
CASE 751U
XXXXX
ALYWX
G
1
TSOP−6
CASE 318G
xxxAYWG
G
1
1
A
L
Y
W, WW
G
= Assembly Location
= Wafer Lot
= Year
= Work Week
= Pb−Free Package
ORDERING INFORMATION
See detailed ordering and shipping information on page 24 of
this data sheet.
•
•
•
•
Operation
Fixed Peak Current & Deep Frequency Foldback @
Light Load Operation.
External Constant Voltage Feedback Adjustment
Cycle by Cycle Peak Current Limit
Built−In Soft−Start
Over & Under Output Voltage Protection
Wide Operation VCC Range (up to 28 V)
Low Start−up Current (2.5 mA typ.) with NCP1361
© Semiconductor Components Industries, LLC, 2015
MARKING
DIAGRAMS
(Note: Microdot may be in either location)
Features
•
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•
Clamped Gate−drive Output for MOSFET
CS & Vs/ZCD pin Short and Open Protection
Internal Temperature Shutdown
Less than 30 mW No−Load Performance at High Line
with NCP1366 Version
These are Pb−Free Devices
Typical Applications
• Low power ac−dc Adapters for Chargers.
• Ac−dc USB chargers for Cell Phones, Tablets and
Cameras
1
Publication Order Number:
NCP1361/D
NCP1361, NCP1366
NCP1361
NCP1366
VCC
1
6
VS/ZCD
GND
2
5
FB
DRV
4
3
CS
VS/ZCD
1
FB
2
CS
DRV
8
HV
3
6
VCC
4
5
GND
(Top View)
(Top View)
Figure 1. Pin Connections
2
Ac
Ac
0
Vout
Prim
3
0
Sec
5
Aux
4
5
6
NCP1366
GND
VCC
4
DRV
3
CS
2
FB
8
HV
1
1
Vs/ZCD
0
Figure 2. NCP1366 Typical Application Circuit
2
Ac
Ac
0
Prim
3
0
Sec
5
Aux
4
5
6
NCP1361
CS
FB
DRV
GND
Vs/ZCD VCC
4
3
1
2
1
0
Figure 3. NCP1361 Typical Application Circuit
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2
Vout
NCP1361, NCP1366
IHV
NCP1366 Only
HV
Vcc
UVLO
Vdd
VCC(Reset)
VCC(OVP)
DbleHiccup
POReset
EN_UVP
VCC and Logic
Management of
double hiccup
Vcc(clamp)
Rlim
POReset
Double_Hiccup_ends
Reset
Soft Start
SS
Blanking
Latch
Vs /
ZCD
Zero Crossing &
Signal Sampling
Sampled Vout
SS
FB_CC
CC
Control
Vref_CC
QR multi−mode
Valley lockout &
Valley Switching &
VCO management
Control Law
&
Primary Peak
Current Control
FB_CV
Vcc
FBint
UVLO
Clamp
S
VCC(OVP)
OVP_Cmp
4 clk
Counter
VDD
DRV
Q
OVP
R
SCP
126% Vref_CV2
RFB
Latch
FB
S
UVP_Cmp
GND
Q
VCC(Reset)
R
POReset
VUVP
Peak current
Freeze
S
Q
VDD
EN_UVP
ICS
UVP
R
DbleHiccup
1/Kcomp
FB Reset
ICS_EN
CS
LEB1
Note:
OVP: Over Voltage Protection
UVP: Under Voltage Protection
OCP: Over Current Protection
SCP: Short Circuit Protection
CBC: CaBle Compensation
tLEB1 > tLEB2
Max_Ipk reset
Count
OCP
Timer
VILIM
OCP
Reset Timer
POReset
DbleHiccup
R
Reset
Counter
LEB2
4 clk
Counter
Q
S
SCP
VCS(Stop)
CS pin Fault
ICS_EN
CS pin Open (VCS > 2 V)
& Short (VCS < 50 mV)
detection is activated at
each startup
Figure 4. Functional Block Diagram: A Version
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3
NCP1361, NCP1366
PIN FUNCTION DESCRIPTION
Pin out
NCP1366
Pin out
NCP1361
Name
Function
1
6
Vs/ZCD
Connected to the auxiliary winding; this pin senses the voltage output for the primary
regulation and detects the core reset event for the Quasi−Resonant mode of operation.
2
5
FB
This pin connects to an optocoupler collector and adjusts the peak current setpoint.
3
4
CS
This pin monitors the primary peak current.
4
3
DRV
Controller switch driver.
5
2
GND
Ground reference.
6
1
VCC
This pin is connected to an external auxiliary voltage and supplies the controller.
7
−
NC
Not Connected for creepage distance between high and low Voltage pins
8
−
HV
Connected the high−voltage rail, this pin injects a constant current into the VCC capacitor for starting−up the power supply.
MAXIMUM RATINGS
Symbol
Rating
Value
Unit
−0.3 to 28
V
+0.4
V/ms
−0.3, VDRV (Note 1)
−300, +500
V
mA
−0.3, 5.5
−2, +5
V
mA
−0.3 to 560
V
Thermal Resistance Junction−to−Air
200
°C/W
Maximum Junction Temperature
150
°C
Operating Temperature Range
−40 to +125
°C
Storage Temperature Range
−60 to +150
°C
2
kV
Machine Model ESD Capability (All pins except DRV) per JEDEC JESD22−A115C
200
V
Charged−Device Model ESD Capability per JEDEC JESD22−C101E
500
V
VCC(MAX)
Maximum Power Supply voltage, VCC pin, continuous voltage
ΔVCC/Δt
Maximum slew rate on VCC pin during startup phase
VDRV(MAX)
IDRV(MAX)
VMAX
IMAX
VHV
RθJ−A
TJ(MAX)
Maximum driver pin voltage, DRV pin, continuous voltage
Maximum current for DRV pin
Maximum voltage on low power pins (except pins DRV and VCC)
Current range for low power pins (except pins DRV and VCC)
High Voltage pin voltage
Human Body Model ESD Capability per JEDEC JESD22−A114F
Stresses exceeding those listed in the Maximum Ratings table may damage the device. If any of these limits are exceeded, device functionality
should not be assumed, damage may occur and reliability may be affected.
1. VDRV is the DRV clamp voltage VDRV(high) when VCC is higher than VDRV(high). VDRV is VCC otherwise
2. This device contains latch−up protection and exceeds 100 mA per JEDEC Standard JESD78.
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4
NCP1361, NCP1366
ELECTRICAL CHARACTERISTICS: (VCC = 12 V, CDRV = 1 nF, For typical values TJ = 25°C, for min/max values TJ = −40°C to
+125°C, Max TJ = 150°C, unless otherwise noted)
Characteristics
Conditions
Symbol
Min
Typ
Max
Unit
HIGH VOLTAGE STARTUP SECTION (NCP1366 only)
Startup current sourced by VCC
pin
VHV = 100 V
IHV
70
100
150
mA
Leakage current at HV
VHV = 400 V
IHV_LKG
−
0.1
1
mA
IHV = 95% of IHV@VHV = 100 V, VCC =
VCC(on) − 0.2 V
VHV(min)
−
22
25
V
Minimum Start−up HV voltage
SUPPLY SECTION AND VCC MANAGEMENT
VCC level at which driving
pulses are authorized
VCC increasing
VCC(on)
16
18
20
V
VCC level at which driving
pulses are stopped
VCC decreasing
VCC(off)
6.0
6.5
7.0
V
VCC(reset)
−
5.6
−
V
VCC(Clamp)
−
4.2
−
V
Minimal current into VCC pin
that keeps the controller
Latched (NCP1366, A & C fault
mode version)
ICC(Clamp)
−
−
20
mA
Minimal current into VCC pin
that keeps the controller
Latched (NCP1361, A & C fault
mode version)
ICC(Clamp)
−
−
6
mA
Rlim
−
7
−
kW
Over Voltage threshold
VCC(OVP)
24
26
28
V
VCC < VCC(on) & VCC increasing from
0V
ICC1
−
2.5
5.0
mA
Internal IC consumption,
steady state
Fsw = 65 kHz, CDRV = 1 nF
ICC2
−
1.7
2.5
mA
Internal IC consumption,
frequency foldback mode
VCO mode, Fsw = 1 kHz, CDRV = 1 nF
ICC3
−
0.8
1.2
mA
VCO mode, Fsw = fVCO(min),
VComp = GND, CDRV = 1 nF
fVCO(min) = 200 Hz
fVCO(min) = 600 Hz
fVCO(min) = 1.2 kHz
ICC4
VComp = VComp(max), VCS increasing
Internal Latch / Logic Reset
Level
VCC clamp level
VCC clamp level (A & C
version)
Activated after Latch protection @ ICC =
100 mA
Current−limit resistor in series
with the latch SCR
Over Voltage Protection
Start−up supply current,
controller disabled or latched
(Only valid with NCP1361 )
Internal IC consumption when
STBY mode is activated
mA
−
−
−
200
220
270
250
TBD*
TBD*
VILIM
0.76
0.80
0.84
V
tLEB1
250
300
360
ns
CURRENT COMPARATOR
Current Sense Voltage
Threshold
Cycle by Cycle Leading Edge
Blanking Duration
Cycle by Cycle Current Sense
Propagation Delay
VCS > (VILIM+ 100 mV) to DRV turn−off
tILIM
−
50
100
ns
Timer Delay Before Latching in
Overload Condition
When CS pin w VILIM
(Note 3)
TOCP
50
70
90
ms
Product parametric performance is indicated in the Electrical Characteristics for the listed test conditions, unless otherwise noted. Product
performance may not be indicated by the Electrical Characteristics if operated under different conditions.
3. The timer can be reset if there are 4 DRV cycles without overload or short circuit conditions
4. Guaranteed by Design.
* Characterization upon request
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5
NCP1361, NCP1366
ELECTRICAL CHARACTERISTICS: (VCC = 12 V, CDRV = 1 nF, For typical values TJ = 25°C, for min/max values TJ = −40°C to
+125°C, Max TJ = 150°C, unless otherwise noted)
Characteristics
Conditions
Symbol
Min
Typ
Max
Unit
VCS(stop)
1.08
1.2
1.32
V
tLEB2
−
120
−
ns
VCS(VCO)
−
120
−
mV
Vref_CC
0.98
0.97
1.00
1.00
1.02
1.03
V
RFB
−
20
−
kW
VComp decreasing
VComp decreasing
VComp decreasing
VComp decreasing
VComp increasing
VComp increasing
VComp increasing
VComp increasing
VH2D
VH3D
VH4D
VHVCOD
VHVCOI
VH4I
VH3I
VH2I
−
−
−
−
−
−
−
−
2.50
2.30
2.10
1.90
2.50
2.70
2.90
3.10
−
−
−
−
−
−
−
−
Minimal difference between any
two valleys
VComp increasing or VComp decreasing
DVH
176
−
−
mV
Internal Dead Time generation
for VCO mode
Entering in VCO when VComp is
decreasing and crosses VHVCOD
TDT(start)
−
2
−
ms
Internal Dead Time generation
for VCO mode
Leaving VCO mode when VComp is
increasing and crosses VHVCOI
TDT(ends)
−
1
−
ms
Internal Dead Time generation
for VCO mode
When in VCO mode
VComp = 1.8 V
VComp = 1.3 V
VComp = 0.8 V
VComp < 0.4 V − 200 Hz option (Note 4)
VComp < 0.4 V − 600 Hz option (Note 4)
VComp < 0.4 V − 1.2 kHz option (Note 4)
TDT
−
−
−
−
−
−
6
25
220
5000
1667
833
−
−
−
−
−
−
Minimum Operating Frequency
in VCO Mode
VComp = GND
fVCO(MIN)
150
450
0.9
200
600
1.2
250
750
1.5
Hz
Hz
kHz
−
No
Clamp
80
110
−
N/A
85
117
kHz
kHz
CURRENT COMPARATOR
Threshold for Immediate Fault
Protection Activation
Leading Edge Blanking
Duration for VCS(stop)
Maximum peak current level at
which VCO takes over or
frozen peak current
VComp < 1.9 V, VCS increasing
(~15%VILIM)
REGULATION BLOCK
Internal Voltage reference for
Constant Current regulation
TJ = 25°C
−40°C < TJ < 125°C
Pullup Resistor
Valley Thresholds
Transition from 1st to 2nd valley
Transition from 2nd to 3rd valley
Transition from 3rd to 4th valley
Transition from 4th valley to VCO
Transition from VCO to 4th valley
Transition from 4th to 3rd valley
Transition from 3rd to 2nd valley
Transition from 2nd to 1st valley
V
Maximum Operating Frequency
ms
fMAX
Option
Option
75
103
DEMAGNETIZATION INPUT − ZERO VOLTAGE DETECTION CIRCUIT and VOLTAGE SENSE
VZCD threshold voltage
VZCD decreasing
VZCD(TH)
25
45
65
mV
VZCD Hysteresis
VZCD increasing
VZCD(HYS)
15
30
45
mV
After tBLANK_PD if VZCD < VZCD(short)
Ù Latched
VZCD(short)
30
50
70
mV
VZCD decreasing from 4 V to 0 V
tDEM
−
−
170
ns
Threshold voltage for output
short circuit or aux. winding
short circuit detection
Propagation Delay from valley
detection to DRV high
Product parametric performance is indicated in the Electrical Characteristics for the listed test conditions, unless otherwise noted. Product
performance may not be indicated by the Electrical Characteristics if operated under different conditions.
3. The timer can be reset if there are 4 DRV cycles without overload or short circuit conditions
4. Guaranteed by Design.
* Characterization upon request
www.onsemi.com
6
NCP1361, NCP1366
ELECTRICAL CHARACTERISTICS: (VCC = 12 V, CDRV = 1 nF, For typical values TJ = 25°C, for min/max values TJ = −40°C to
+125°C, Max TJ = 150°C, unless otherwise noted)
Characteristics
Conditions
Symbol
Min
Typ
Max
Unit
DEMAGNETIZATION INPUT − ZERO VOLTAGE DETECTION CIRCUIT and VOLTAGE SENSE
Delay after on−time that the
Vs/ZCD is still pulled to ground
tshort_ZCD
−
0.7
−
ms
tblank_ZCD
1.2
1.5
1.8
ms
Timeout while in Soft−start
Timeout after soft−start complete
toutSS
tout
36
4.5
44
5.5
52
6.5
VCC > VCC(on) VZCD = 4 V, DRV is low
IZCD
−
−
0.1
RSNK
RSRC
−
−
7
12
−
−
(Note 4)
Blanking delay after on−time
(Vs/ZCD pin is disconnected
from the internal circuitry)
Timeout after last
demagnetization transition
Input leakage current
ms
mA
DRIVE OUTPUT − GATE DRIVE
W
Drive resistance
DRV Sink
DRV Source
Rise time
CDRV = 1 nF, from 10% to 90%
tr
−
45
80
ns
Fall time
CDRV = 1 nF, from 90% to 10%
tf
−
30
60
ns
DRV Low voltage
VCC = VCC(off) + 0.2 V,
CDRV = 220 pF, RDRV = 33 kW
VDRV(low)
6.0
−
−
V
DRV High voltage
VCC = VCC(OVP)−0.2 V, CDRV = 220 pF,
RDRV = 33 kW
VDRV(high)
−
−
13.0
V
Current Sense peak current rising from
0.2 V to 0.8 V
tSS
3
4
5
ms
Thermal Shutdown
Device switching (Fsw ∼ 65 kHz)
(Note 4)
TSHTDN
−
150
−
°C
Thermal Shutdown Hysteresis
Device switching (Fsw ∼ 65 kHz)
(Note 4)
TSHTDN(HYS)
−
40
−
°C
Number of Drive cycle before
latch confirmation
VComp = VComp(max),
VCS > VCS(stop)
Or Internal sampled Vout > VOVP
Tlatch_count
−
4
−
−
Fault level detection for OVP Ù
Latched or Double Hiccup
autorecovery (depends on fault
version)
Internal sampled Vout increasing
VOVP = Vref_CV2+26%
Version E
VOVP
2.95
3.15
3.35
V
3.4
3.6
3.8
Fault level detection for UVP Ù
Double Hiccup autorecovery
(UVP detection is disabled
during TEN_UVP)
Internal sampled Vout decreasing
Version A & B
Version C with a 300 mV CBC
Version E
VUVP
1.4
1.516
0.70
1.5
1.625
0.75
1.6
1.733
0.80
Starting at the beginning of the Soft
start
TEN_UVP
−
37
−
ms
When VCS > VCS_min
ICS
−
55
−
mA
CS pin open
VCS(open)
0.8
−
−
V
VCS_min
−
50
70
mV
TCS_short
−
3
−
ms
SOFT START
Internal Fixed Soft Start
Duration
FAULT PROTECTION
Blanking time for UVP
detection
Pull−up Current Source on CS
pin for Open or Short circuit
detection
CS pin Open detection
CS pin Short detection
CS pin Short detection timer
(Note 4)
V
Product parametric performance is indicated in the Electrical Characteristics for the listed test conditions, unless otherwise noted. Product
performance may not be indicated by the Electrical Characteristics if operated under different conditions.
3. The timer can be reset if there are 4 DRV cycles without overload or short circuit conditions
4. Guaranteed by Design.
* Characterization upon request
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7
NCP1361, NCP1366
FAULT MODE STATES TABLE (WHATEVER THE VERSION)
Event
Overcurrent
VCS > VILIM
Timer
Protection
Next Device Status
OCP timer
Double Hiccup
Release to Normal Operation Mode
•
Resume to normal operation: if 4 pulses from FB
Reset & then Reset timer
•
Resume operation after Double Hiccup
Winding short
VCS > VCS(stop)
Immediate
4 consecutive pulses with
VCS > VCS(stop) before
Latching
VCC is decreasing to VCC(clamp) and waiting for unplug
from line VCC < VCC(reset)
CS pin Fault:
Short & Open
Immediate
Double Hiccup
Resume operation after Double Hiccup
Low supply
VCC < VCC(off)
10 ms timer
Double Hiccup
Resume operation after Double Hiccup
Internal TSD
10 ms timer
Double Hiccup
Resume operation after Double Hiccup & T < (TSHTDN
− TSHTDN(Hyst))
ZCD short
VZCD < VZCD(short) after
tBLANK_PD time
Immediate
Double Hiccup
Resume operation after Double Hiccup (VCC(on) < VCC
< VCC(reset))
FAULT MODE STATES TABLE (ACCORDING TO THE CONTROLLER VERSIONS)
Event
A Version
B Version
C Version
High supply
VCC > VCC(ovp)
Latched_Timer
Autorecovery
Latched_Timer
Internal Vout
OVP: Vout > 126% Vref_CV2
Latched_4clk
Autorecovery
Latched_4clk
Internal Vout
UVP: Vout < 60%
Vref_CV2, when Vout is decreasing only
Autorecovery
Autorecovery
Latched_Timer
FAULT TYPE MODE DEFINITION
Fault Mode
Timer Protection
Next Device Status
Release to Normal Operation Mode
Latched_Timer
10 ms timer
Latched
VCC is decreasing to VCC(clamp) and waiting for unplug from line VCC < VCC(reset)
Latched_4clk
Immediate
4 consecutive pulses with
VCS > 126% Vref_CV2 before
Latching
VCC is decreasing to VCC(clamp) and waiting for unplug from line VCC < VCC(reset)
Autorecovery
Immediate
Resume operation after
Double Hiccup
Resume operation after Double Hiccup (VCC(on) <
VCC < VCC(reset))
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NCP1361, NCP1366
CHARACTERIZATION CURVES
20
7.0
19.5
6.9
6.8
19
VCC(off) (V)
VCC(on) (V)
6.7
18.5
18
17.5
6.6
6.5
6.4
6.3
17
6.2
16.5
16
−50
6.1
−25
0
25
50
75
100
125
6.0
−50
150
75
100
125
TJ, TEMPERATURE (°C)
6.4
27.5
150
27.0
VCC(OVP) (V)
6.0
VCC(reset) (V)
50
Figure 6. VCC Minimum Operating versus
Temperature
6.2
5.8
5.6
5.4
5.2
26.5
26.0
25.5
25.0
5.0
24.5
4.8
−25
0
25
50
75
100
125
24.0
−50
150
−25
0
25
50
75
100
125
TJ, TEMPERATURE (°C)
TJ, TEMPERATURE (°C)
Figure 7. VCC(reset) versus Temperature
Figure 8. VCC(OVP) versus Temperature
160
1.0
150
0.9
140
0.8
130
0.7
IHV_LKG (mA)
IHV (mA)
25
TJ, TEMPERATURE (°C)
28.0
120
110
100
0.5
0.4
0.3
80
0.2
70
0.1
−25
0
25
50
75
100
125
150
150
0.6
90
60
−50
0
Figure 5. VCC Startup Threshold versus
Temperature
6.6
4.6
−50
−25
0
−50
−25
0
25
50
75
100
125
150
TJ, TEMPERATURE (°C)
TJ, TEMPERATURE (°C)
Figure 9. Startup Current Source versus
Temperature
Figure 10. HV Pin Leakage versus Temperature
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NCP1361, NCP1366
CHARACTERIZATION CURVES
2.4
24
2.0
ICC2 (mA)
18
16
1.8
1.6
14
1.4
12
1.2
10
−50
ICC3 (mA)
2.0
20
−25
0
25
50
75
100
125
1.0
−50
150
0
25
50
75
100
125
TJ, TEMPERATURE (°C)
TJ, TEMPERATURE (°C)
Figure 12. ICC2 versus Temperature
1.00
0.25
0.95
0.24
0.90
0.23
0.85
0.22
0.80
0.75
0.70
0.20
0.19
0.18
0.17
0.60
0.16
0.55
0.15
−25
0
25
50
75
100
125
0.14
−50
150
−25
0
25
50
75
100
125
TJ, TEMPERATURE (°C)
TJ, TEMPERATURE (°C)
Figure 13. ICC3 versus Temperature
Figure 14. Standby Current Consumption
(200 Hz option) versus Temperature
0.84
150
0.21
0.65
0.50
−50
−25
Figure 11. Minimum Voltage for HV Startup
Current Source versus Temperature
ICC4 (mA)
VHV(min) (V)
22
150
1.32
1.30
0.83
1.26
0.81
1.24
VCS(stop) (V)
VILIM (V)
1.28
0.82
0.80
0.79
1.20
1.18
1.16
0.78
1.14
0.77
0.76
−50
1.22
1.10
−25
0
25
50
75
100
125
150
1.08
−50
−25
0
25
50
75
100
125
150
TJ, TEMPERATURE (°C)
TJ, TEMPERATURE (°C)
Figure 15. Max Peak Current Limit versus
Temperature
Figure 16. Second Peak Current Limit for Fault
Protection versus Temperature
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10
NCP1361, NCP1366
CHARACTERIZATION CURVES
1.02
Vref_CC (V)
1.01
1.00
0.99
0.98
−50
−25
0
25
50
75
100
125
150
TJ, TEMPERATURE (°C)
1.60
3.35
1.58
3.30
1.56
3.25
1.54
3.20
1.52
3.15
3.10
1.50
1.48
3.05
1.46
3.00
1.44
2.95
1.42
2.90
−50
tLEB1 (ns)
VUVP (V)
3.40
−25
0
25
50
75
100
125
1.40
−50
150
0
25
50
75
100
125
150
TJ, TEMPERATURE (°C)
Figure 18. Output Over Voltage Level versus
Temperature
Figure 19. Output Under Voltage Level versus
Temperature
360
180
340
160
320
140
300
120
280
100
260
80
240
−50
−25
TJ, TEMPERATURE (°C)
tLEB2 (ns)
VOVP (V)
Figure 17. Internal Voltage Reference for
Constant Current Regulation versus
Temperature
−25
0
25
50
75
100
125
150
60
−50
−25
0
25
50
75
100
125
150
TJ, TEMPERATURE (°C)
TJ, TEMPERATURE (°C)
Figure 20. Cycle−by−Cycle Leading Edge
Blanking Duration versus Temperature
Figure 21. Leading Edge Blanking Duration for
VCS(stop) Level versus Temperature
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11
NCP1361, NCP1366
CHARACTERIZATION CURVES
100
52
50
48
60
toutSS (ms)
tILIM (ns)
80
40
46
44
42
40
20
38
−25
0
25
50
75
100
125
36
−50
150
0
25
50
75
100
125
150
TJ, TEMPERATURE (°C)
TJ, TEMPERATURE (°C)
Figure 23. Timeout After Last Demagnetization
Transition in Soft−Start versus Temperature
6.5
95
6.3
90
6.1
85
5.9
80
5.7
5.5
5.3
75
70
65
5.1
60
4.9
55
4.7
50
4.5
−50
−25
Figure 22. Cycle−by−Cycle Current Sense
Propagation Delay versus Temperature
TOCP (ms)
tout (ms)
0
−50
−25
0
25
50
75
100
125
45
−50
150
−25
0
25
50
75
100
125
TJ, TEMPERATURE (°C)
TJ, TEMPERATURE (°C)
Figure 24. Timeout After Last Demagnetization
Transition versus Temperature
Figure 25. Timer Delay Before Latching in
Overload Condition versus Temperature
65
150
45
60
40
VZCD(HYS) (mV)
VZCD(TH) (mV)
55
50
45
40
35
30
25
35
20
30
25
−50
−25
0
25
50
75
100
125
150
15
−50
−25
0
25
50
75
100
125
TJ, TEMPERATURE (°C)
TJ, TEMPERATURE (°C)
Figure 26. Zero Voltage Detection Threshold
Voltage versus Temperature
Figure 27. Zero Voltage Detection Hysteresis
versus Temperature
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12
150
NCP1361, NCP1366
CHARACTERIZATION CURVES
1.8
8.0
7.8
7.6
7.4
1.6
VDRV(low) (V)
Tblank_ZCD (ms)
1.7
1.5
1.4
7.2
7.0
6.8
6.6
6.4
1.3
6.2
1.2
−50
−25
0
25
50
75
100
125
6.0
−50
150
−25
0
25
50
75
100
125
TJ, TEMPERATURE (°C)
TJ, TEMPERATURE (°C)
Figure 28. Blanking Delay for ZCD Detection
versus Temperature
Figure 29. VDRV(low) versus Temperature
13.0
150
80
70
12.5
tr (ns)
50
11.5
40
30
11.0
20
10.5
10.0
−50
10
−25
0
25
50
75
100
125
0
−50
150
−25
0
25
50
75
100
125
TJ, TEMPERATURE (°C)
TJ, TEMPERATURE (°C)
Figure 30. VDRV(high) versus Temperature
Figure 31. Gate Drive Rise Time versus
Temperature
60
50
40
tf (ns)
VDRV(high) (V)
60
12.0
30
20
10
0
−50
−25
0
25
50
75
100
125
TJ, TEMPERATURE (°C)
Figure 32. Gate Drive Fall Time versus
Temperature
www.onsemi.com
13
150
150
NCP1361, NCP1366
CHARACTERIZATION CURVES
130
70
65
125
VZCD(short) (mV)
VCS(VCO) (mV)
60
120
115
110
55
50
45
40
105
35
−25
0
25
50
75
100
125
30
−50
150
−25
0
25
50
75
100
125
TJ, TEMPERATURE (°C)
TJ, TEMPERATURE (°C)
Figure 33. Minimum or Frozen Peak Current on
CS Pin versus Temperature
Figure 34. Threshold Level for Detecting
Output or Aux. Winding Short versus
Temperature
40
75
39
70
38
65
37
60
36
55
ICS (mA)
TEN_UVP (ms)
100
−50
35
34
50
45
33
40
32
35
31
30
30
−50
−25
0
25
50
75
100
125
25
−50
150
150
−25
0
25
50
75
100
125
TJ, TEMPERATURE (°C)
TJ, TEMPERATURE (°C)
Figure 35. Startup Blanking Time for UVP
Detection versus Temperature
Figure 36. Pull−up Current Source for
Detecting Open or Short on CS Pin versus
Temperature
150
1.20
75
70
1.10
65
VCS(open) (V)
VCS_min (mV)
60
55
50
45
40
35
1.00
0.90
0.80
0.70
30
25
−50
−25
0
25
50
75
100
125
150
0.60
−50
−25
0
25
50
75
100
125
TJ, TEMPERATURE (°C)
TJ, TEMPERATURE (°C)
Figure 37. CS Pin Short Detection Threshold
versus Temperature
Figure 38. CS Pin Open Detection Threshold
versus Temperature
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14
150
NCP1361, NCP1366
APPLICATION INFORMATION
Vout
The NCP1366/61 is a flyback power supply controller
providing a means to implement primary side
constant−current regulation. This technique does not need a
secondary side feedback circuitry, associated bias current
and an opto−coupler. NCP1366/61 implements a
current−mode architecture operating in quasi−resonant
mode. The controller prevents valley−jumping instability
and steadily locks out in a selected valley as the power
demand goes down. As long as the controller is able to detect
a valley, the new cycle or the following drive remains in a
valley. Due to a dedicated valley detection circuitry
operating at any line and load conditions, the power supply
efficiency will always be optimized. In order to prevent any
high switching frequency two frequency clamp options are
available.
• Quasi−Resonance Current−mode operation:
implementing quasi−resonance operation in peak
current−mode control optimizes the efficiency by
switching in the valley of the MOSFET drain−source
voltage. Due to a proprietary circuitry, the controller
locks−out in a selected valley and remains locked until
the input voltage significantly changes. Only the four
first valleys could be locked out. When the load current
diminishes, valley switching mode of operation is kept
but without valley lock−out. Valley−switching
operation across the entire input/output conditions
brings efficiency improvement and lets the designer
build higher−density converters.
• Frequency Clamp: As the frequency is not fixed and
dependent on the line, load and transformer
specifications, it is important to prevent switching
frequency runaway for applications requiring maximum
switching frequencies up to 90 kHz or 130 kHz. Two
frequency clamp options at 80 kHz or 110 kHz are
available for this purpose. In case frequency clamp is
not needed, a specific version of the 1361/66 exists in
which the clamp is deactivated.
• Primary Side Constant Current Regulation: Battery
charging applications request constant current
regulation. NCP1361/66 controls and regulates the
output current at a constant level regardless of the input
and output voltage conditions. This function offers tight
over power protection by estimating and limiting the
maximum output current from the primary side, without
any particular sensor.
• Optocoupler−based feedback: the voltage feedback
loop is classically implemented with an optocoupler
and a NCP431 voltage reference in the secondary side.
By pulling the feedback pin low, the controller adjusts
the peak current setpoint and regulates Vout.
Vnom
Optocoupler−based feedback
Primary−side
CC mode
0
Inom
Iout
Figure 39. Constant−Voltage & Constant−Current
Mode
• Soft−Start: 4 ms internal fixed soft start guarantees a
•
•
•
peak current starting from zero to its nominal value
with smooth transition in order to prevent any
overstress on the power components at each startup.
Cycle−by−Cycle peak current limit: If the max peak
current reaches the VILIM level, the over current
protection timer is enabled and starts counting. If the
overload lasts TOCP delay, then the fault is latched and
the controller stops immediately driving the power
MOSFET. The controller enters in a double hiccup
mode before autorecovering with a new startup cycle.
VCC Over Voltage Protection: If the VCC voltage
reaches the VCC(OVP) threshold the controller enters in
latch mode. Thus it stops driving pulse on DRV pin:
♦ A & C version − (Latched VCC(OVP)): VCC
capacitor is internally discharged to the VCC(Clamp)
level with a very low power consumption: the
controller is completely disabled. Resuming
operation is possible by unplugging the line in order
to releasing the internal VCC thyristor with a VCC
current lower than the ICC(Clamp).
♦ B version − (Autorecovery): it enters in double
hiccup mode before resuming operation.
Winding Short−Circuit Protection: An additional
comparator senses the CS signal and stops the
controller if VCS reaches VILIM +50% (after a reduced
LEB: tLEB2 ). Short circuit protection is enabled only if
4 consecutive pulses reach SCP level. This small
counter prevents any false triggering of short circuit
protection during surge test for instance. This fault is
latched and operations will be resumed like in a case of
VCC Over Voltage Protection.
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15
NCP1361, NCP1366
• Vout Over Voltage Protection: if the internally−built
•
•
•
power mosfet until the junction temperature decreases
by TSHTDN(HYS) , then the operation is resumed after a
double hiccup mode.
output voltage becomes higher than VOVP level
(Vref_CV1 + 26%) a fault is detected.
♦ A & C version: This fault is latched and operations
are resumed like in the VCC Over Voltage Protection
case.
♦ B version: the part enters in double hiccup mode
before resuming operations.
Vout Under Voltage Protection: After each circuit
power on sequence, Vout UVP detection is enabled only
after the startup timer TEN_UVP. This timer ensures that
the power supply is able to fuel the output capacitor
before checking the output voltage in on target. After
this startup blanking time, UVP detection is enabled
and monitors the Output voltage level. When the power
supply is running in constant−current mode and when
the output voltage falls below VUVP level, the controller
stops sending drive pulses and enters a double hiccup
mode before resuming operations (A & B version), or
latches off (C version).
Vs/ZCD Pin Short Protection: at the beginning of
each off−time period, the Vs /ZCD pin is tested to check
whether it is shorted or left open. In case a fault is
detected, the controller enters in a double hiccup mode
before resuming operations.
Temperature Shutdown: if the junction temperature
reaches the TSHTDN level, the controller stop driving the
Startup Operation
The high−voltage startup current source is connected to
the bulk capacitor via the HV pin, it charges the VCC
capacitor. During startup phase, it delivers 100 mA to fuel the
VCC capacitor. When VCC pin reaches VCC(on) level, the
NCP1361/66 is enabled. Before sending the first drive pulse
to the power MOSFET, the CS pin has been tested for an
open or shorted situation. If CS pin is properly wired, then
the controller sends the first drive pulse to the power
MOSFET. After sending these first pulses, the controller
checks the correct Vs/ZCD pin wiring. Considering the
Vs/ZCD pin properly wired, the controller engages a
softstart sequence. The softstart sequence controls the max
peak current from the minimal frozen primary peak current
(VCS(VCO) = 120 mV: 15% of VILIM ) to the nominal pulse
width by smoothly increasing the level.
Figure 40 illustrates a standard connection of the HV pin
to the bulk capacitor. If the controller is in a latched fault
mode (ex VCC_OVP has been detected), the power supply will
resume the operation after unplugging the converter from
the ac line outlet. Due the extremely low controller
consumption in latched mode, the release of the latch could
be very long. The unplug duration for releasing the latch will
be dependent on the bulk capacitor size.
Vbulk
RHV
L
1
Vs/ZCD
N
2
FB
HV
8
2
CS
Vcc
6
4
DRV
GND
5
CVcc
Vaux
Figure 40. HV Startup Connection to the Bulk Capacitor (NCP1366)
Protecting the Controller Against Negative Spikes
The following calculation illustrates the time needed for
releasing the latch state:
t unplug u
C bulkV in_ac Ǹ2
As with any controller built upon a CMOS technology, it
is the designer’s duty to avoid the presence of negative
spikes on sensitive pins. Negative injection has the bad habit
to forward−bias the controller substrate and can induce
erratic behaviors. Sometimes, the injection can be so strong
that internal parasitic SCRs are triggered and latch the
controller. The HV pin can be the problem in certain
circumstances. During the turn−off sequence, e.g. when the
user unplugs the power supply, the controller is still fed by
its VCC capacitor and keeps activating the MOSFET ON and
(eq. 1)
I HV
For the following typical application with a 10 mF bulk
capacitor and a wide mains input range, in the worst case the
power supply needs to be unplug at least for 38 seconds @
265 V ac and 12 seconds @ 85 Vac. It is important to note
that the previous recommendation is no longer valid with the
B version, as all the faults are set to autorecovery mode only.
www.onsemi.com
16
NCP1361, NCP1366
OFF with a peak current limited by Rsense . Unfortunately, if
the quality factor Q of the resonating network formed by Lp
and Cbulk is high (e.g. the MOSFET RDS(on) + Rsense are
small), conditions are met to make the circuit resonate and
a negative ringing can potentially appear at the HV pin.
Simple and inexpensive cures exist to prevent the internal
parasitic SCR activation. One of them consist of inserting a
resistor in series with the HV pin to keep the negative current
at the lowest when the bulk swings negative (Figure 40).
Another option (Figure 41) consists of connecting the
HV pin directly to the line or neutral input via a high−voltage
diode. This configuration offers the benefits to release a
latch state immediately after unplugging the power supply
from the mains outlet. There is no delay for resetting the
controller as there no capacitor keeps the HV bias.
RHV resistor value must be sized as follow in order to
guarantee a correct behavior of the HV startup in the worst
case conditions:
R HV t
V in,ac_min Ǹ2 * V HV(min)_max
Where:
• Vin,ac_min is minimal input voltage, for example 85 V ac
for universal input mains.
• VHV(min)_max is the worst case of the minimal input
voltage needed for the HV startup current source
(25 V−max).
• IHV_max is the maximum current delivered by the HV
startup current source (150 mA−max)
With this typical example
R HV t
85 Ǹ2 * 25
150 m
+ 633 kW,
then any value below this one will be ok.
Vbulk
L
1 Vs/ZCD
N
2
HV
8
FB
2
CS
VCC
6
4
DRV
GND
5
CVcc
Vaux
Figure 41. Recommended HV Startup Connection for Fast Release after a Latched Fault (NCP1366)
Primary Side Regulation: Constant Current Operation
Figure 42 portrays idealized primary and secondary
transformer currents of a flyback converter operating in
Discontinuous Conduction Mode (DCM).
Ip (t)
I p , pk
time
Is(t), IOUT
I s , pk =
I p , pk
N ps
IOUT = <Is(t)>
ton
(eq. 2)
I HV_max
time
tdemag
tsw
Figure 42. Primary and Secondary Transformer Current Waveforms
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17
NCP1361, NCP1366
When the primary power MOSFET is turned on, the
primary current is illustrated by the green curve of
Figure 42. When the power MOSFET is turned off the
primary side current drops to zero and the current into the
secondary winding immediately rises to its peak value equal
to the primary peak current divided by the primary to
secondary turns ratio. This is an ideal situation in which the
leakage inductance action is neglected.
The output current delivered to the load is equal to the
average value of the secondary winding current, thus we can
write:
I out +t i sec(t) u+
I p,pk t demag
V FB_CC + V ref_CC
I out +
R sense +
V ref_CC
(eq. 8)
8N psI out
When the power MOSFET is released at the end of the on
time, because of the transformer leakage inductance and the
drain lumped capacitance some voltage ringing appears on
the drain node. These voltage ringings are also visible on the
auxiliary winding and could cheat the controller detection
circuits. To avoid false detection operations, two protecting
circuits have been implemented on the Vs /ZCD pin (see
Figure 43):
1. An internal switch grounds the Vs /ZCD pin during
ton +tshort_ZCD in order to protect the pin from
negative voltage.
2. In order to prevent any misdetection from the zero
crossing block an internal switch disconnects
Vs /ZCD pin until tblank_ZCD time (1.5 ms typ.)
ends.
(eq. 4)
Np
sense resistor on CS pin:
V CS
(eq. 7)
8N psR sense
(eq. 3)
• Ip,pk is the magnetizing peak current sensed across the
I p,pk +
V ref_CC
The output current value is set by choosing the sense
resistor value:
2N ps t sw
Ns
(eq. 6)
As the controller monitors the primary peak current via the
sense resistor and due to the internal current setpoint divider
(Kcomp ) between the CS pin and the internal feedback
information, the output current could be written as follow:
Where:
• tsw is the switching period
• tdemag is the demagnetizing time of the transformer
• Nps is the secondary to primary turns ratio, where Np
and Ns are respectively the transformer primary and
secondary turns:
N ps +
t sw
t demag
(eq. 5)
R sense
Internal constant current regulation block is building the
constant current feedback information as follow:
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18
NCP1361, NCP1366
Figure 43. Vs /ZCD Pin Waveforms
Constant−Current and Constant−Voltage Overall
Regulation:
demagnetization end is detected by monitoring the
transformer auxiliary winding voltage. Turning on the
power switch once the transformer is demagnetized (or
reset) reduces turn−on switching losses. Once the
transformer is demagnetized, the drain voltage starts ringing
at a frequency determined by the transformer magnetizing
inductance and the drain lumped capacitance, eventually
settling at the input voltage value. A QR controller takes
advantage of the drain voltage ringing and turns on the
power switch at the drain voltage minimum or “valley” to
reduce turn−on switching losses and electromagnetic
interference (EMI).
As sketched by Figure 44, a valley is detected once the
ZCD pin voltage falls below the QR flyback
demagnetization threshold, VZCD(TH) , typically 45 mV. The
controller will switch once the valley is detected or
increment the valley counter depending on FB voltage.
As already presented in the two previous paragraphs, the
controller integrates two different feedback loops: the first
one deals with the constant−current regulation scheme while
the second one builds the constant−voltage regulation with
an opto−based voltage loop. One of the two feedback paths
sets the primary peak current into the transformer. During
startup phase, however, the peak current is controlled by the
soft−start.
Zero Current Detection
The NCP1361/66 integrates a quasi−resonant (QR)
flyback controller. The power switch turn−off of a QR
converter is determined by the peak current whose value
depends on the feedback loop. The switch restart event is
determined by the transformer demagnetization end. The
ZCD
QR multi−mode
Valley lockout &
Valley Switching &
VCO management
Rs1
Rs2
VZCD(TH)
Blanking
Tblank_ZCD
Timeout
(toutSS or tout)
Figure 44. Valley Lockout Detection Circuitry internal Schematic
www.onsemi.com
19
S
Q
R
DRV
(Internal)
NCP1361, NCP1366
• Valley #1: the timeout delay must run twice so that the
Timeout
The ZCD block actually detects falling edges of the
auxiliary winding voltage applied to the ZCD pin. At
start−up or during other transient phases, the ZCD
comparator may be unable to detect such an event. Also, in
the case of extremely damped oscillations, the system may
not succeed in detecting all the valleys required by valley
lockout operation (VLO, see next section). In this condition,
the NCP1361/66 ensures continued operation by
incorporating a maximum timeout period that resets itself
when a demagnetization phase is properly detected. In case
the ringing signal is too weak or heavily damped, the timeout
signal supersedes the ZCD signal for the valley counter.
Figure 44 shows the timeout period generator circuit
schematic. The timeout duration, tout , is set to 5.5 ms (typ.).
During startup, the output voltage is still low, leading to
long demagnetization phase, difficult to detect since the
auxiliary winding voltage is small as well. In this condition,
the tout timeout is generally shorter than the inductor
demagnetization period and if used to restart a switching
cycle, it can cause continuous current mode (CCM)
operation for a few cycles until the voltage on the ZCD pin
is high enough for proper valleys detection. A longer
timeout period, toutSS , (typically 44 ms) is therefore set
during soft−start to prevent CCM operation.
In VLO operation, the timeout occurrences are counted
instead of valleys when the drain−source voltage
oscillations are too damped to be detected. For instance,
assume the circuit must turn on at the third valley and the
ZCD ringing only enables the detection of:
• Valleys #1 to #2: the circuit generates a DRV pulse tout
(steady−state timeout delay) after valley #2 detection.
circuit generates a DRV pulse 10 ms (2*tout typ.) after
valley #1 detection.
Valley LockOut (VLO) and Frequency Foldback (FF)
The operating frequency of a traditional Quasi−Resonant
(QR) flyback controller is inversely proportional to the
system load. In other words, a load reduction increases the
operating frequency. A maximum frequency clamp can be
useful to limit the operating frequency range. However,
when associated with a valley−switching circuit,
instabilities can arise because of the discrete frequency
jumps. The controller tends to hesitate between two valleys
and audible noise can be generated
To avoid this issue, the NCP1361/66 incorporates a
proprietary valley lockout circuitry which prevents
so−called valley jumping. Once a valley is selected, the
controller stays locked in this valley until the input level or
output power changes significantly. This technique extends
QR operation over a wider output power range while
maintaining good efficiency and naturally limiting the
maximum operating frequency.
The operating valley (from 1st to 4th valley) is determined
by the internal feedback level (FB node on Figure 4). As FB
voltage level decreases or increases, the valley comparators
toggle one after another to select the proper valley.
The decimal counter increases each time a valley is
detected. The activation of an “n” valley comparator blanks
the “n−1” or “n+1” valley comparator output depending if
VFB decreases or increases, respectively. Figure 45 shows a
typical frequency characteristic obtained at low line in a
10 W charger.
Figure 45. Typical Switching Frequency versus Output Power Relationship in a 10 W Adapter
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20
NCP1361, NCP1366
When an “n” valley is asserted by the valley selection
circuitry, the controller locks in this valley until the FB
voltage decreases to the lower threshold (“n+1” valley
activates) or increases to the “n valley threshold” + 600 mV
(“n−1” valley activates). The regulation loop adjusts the
peak current to deliver the necessary output power at the
valley operating point. Each valley selection comparator
features a 600 mV hysteresis that helps stabilize operation
despite the FB voltage swing produced by the regulation
loop.
Table 1. VALLEY FB THRESHOLD ON CONSTANT VOLTAGE REGULATION
FB Falling
FB Rising
1st to 2nd valley
2.5 V
FF mode to 4th
2.5 V
2nd to 3rd valley
2.3 V
4th to 3rd valley
2.7 V
3rd to 4th valley
2.1 V
3rd to 2nd valley
2.9 V
1.9 V
2nd
3.1 V
4th
to FF mode
Frequency Foldback (FF)
to
1st
valley
efficiency benefit inherent to the QR operation, the
controller turns on again with the next valley after the dead
time has ended. As a result, the controller will still run in
valley switching mode even when the FF is enabled. This
dead−time increases when the FB voltage decays. There is
no discontinuity when the system transitions from VLO to
FF and the frequency smoothly reduces as FB goes below
1.9 V.
The dead−time is selected to generate a 2 ms dead−time
when VComp is decreasing and crossing VHVCOD (1.9 V
typ.). At this moment, it can linearly go down to the minimal
frequency limit (fVCO(min) = 200, 600 or 1200 Hz version are
available). The generated dead−time is 1ms when VComp is
increasing and crossing VHVCOI (2.5 V typ.).
As the output current decreases (FB voltage decreases),
the valleys are incremented from 1 to 4. In case the fourth
valley is reached, the FB voltage further decreases below
1.9 V and the controller enters the frequency foldback mode
(FF). The current setpoint being internally forced to remain
above 0.12 V (setpoint corresponding to VComp = 1.9 V), the
controller regulates the power delivery by modulating the
switching frequency. When an output current increase
causes FB to exceed the 2.5 V FF upper threshold (600−mV
hysteresis), the circuit recovers VLO operation.
In frequency foldback mode, the system reduces the
switching frequency by adding some dead−time after the 4th
valley is detected. However, in order to keep the high
Figure 46. Valley Lockout Threshold
Current Setpoint
starting from the frozen peak current (VCS(VCO) = 120 mV
typ.) to VILIM (0.8 V typ.) within 4 ms (tss ).
However, this internal FB value is also limited by the
following functions:
♦ A minimum setpoint is forced that equals VCS(VCO)
(0.12 V, typ.)
♦ In addition, a second OCP comparator ensures that
in any case the current setpoint is limited to VILIM .
As explained in this operating description, the current
setpoint is affected by several functions. Figure 47
summarizes these interactions. As shown by this figure, the
current setpoint is the output of the control law divided by
Kcomp (4 typ.). This current setpoint is clamped by the
soft−start slope as long as the peak current requested by the
FB_CV or FB_CC level are higher. The softstart clamp is
www.onsemi.com
21
NCP1361, NCP1366
This ensures the MOSFET current setpoint remains
limited to VILIM in a fault condition.
Peak current
Freeze
SoftStart
Control Law
For
Primary Peak
Current Control
FB_CV
FB_CC
PWM Comp
1/Kcomp
FB Reset
CS
PWM
Latch
Reset
OCP
Comp
LEB1
Max_Ipk reset
RCS
Rsense
CCS
Count
VILIM
OCP
OCP
Timer
Reset Timer
POReset
DbleHiccup
Short Circuit
Comp
LEB2
Reset
Counter
4 clk
Counter
SCP
VCS(Stop)
Figure 47. Current Setpoint
Fault mode and Protection
A 2nd Over−Current Comparator for Abnormal
Overcurrent Fault Detection
♦
A severe fault like a winding short−circuit can cause the
switch current to increase very rapidly during the on−time.
The current sense signal significantly exceeds VILIM . But,
because the current sense signal is blanked by the LEB
circuit during the switch turn on, the power switch current
can abnormally increase, possibly causing system damages.
The NCP1361/66 protects against this dangerous mode by
adding an additional comparator for abnormal overcurrent
fault detection or short−circuit condition. The current sense
signal is blanked with a shorter LEB duration, tLEB2 ,
typically 120 ns, before applying it to the short−circuit
comparator. The voltage threshold of this extra comparator,
VCS(stop) , is typically 1.2 V, set 50% higher than VILIM . This
is to avoid interference with normal operation. Four
consecutive abnormal overcurrent faults cause the
controller to enter in auto−recovery mode. The count to 4
provides noise immunity during surge testing. The counter
is reset each time a DRV pulse occurs without activating the
fault overcurrent comparator or after double hiccup
sequence or if the power supply is unplugged with a new
startup sequence after the initial power on reset.
♦
CS pin: at each startup, a 55 mA (ICS ) current source
pulls up the CS pin to disable the controller if the pin
is left open or grounded. Then the controller enters
in a double hiccup mode.
Vs/ZCD pin: after sending the first drive pulse the
controller checks the correct wiring of Vs/ZCD pin:
after the ZCD blanking time, if there is an open or
short conditions, the controller enters in double
hiccup mode.
Thermal Shutdown: An internal thermal shutdown circuit
monitors the junction temperature of the IC. The controller
is disabled if the junction temperature exceeds the thermal
shutdown threshold (TSHDN ), typically 150°C. A continuous
VCC hiccup is initiated after a thermal shutdown fault is
detected. The controller restarts at the next VCC(on) once the
IC temperature drops below TSHDN reduced by the thermal
shutdown hysteresis (TSHDN(HYS)), typically 40°C. The
thermal shutdown is also cleared if VCC drops below
VCC(reset). A new power up sequences commences at the
next VCC(on) once all the faults are removed.
Driver
The NCP1361/66 maximum supply voltage, VCC(max), is
28 V. Typical high−voltage MOSFETs have a maximum
gate voltage rating of 20 V. The DRV pin incorporates an
active voltage clamp which limits the gate voltage on the
external mosfet. The DRV voltage clamp, VDRV(high) is set to
13 V maximum.
Standby Power Optimization
Assuming the no−load standby power is a critical
parameter, the NCP1361/66 is optimized to reach an ultra
low standby power. When the controller enters standby
mode, a part of the internal circuitry has been disabled in
order to minimize its supply current. When the STBY mode
is enabled, the consumption is only 200 mA (ICC4 ) with the
200 Hz minimal frequency option.
www.onsemi.com
22
NCP1361, NCP1366
TABLE OF AVAILABLE OPTIONS
Function
Options
Fault Mode
VCC_OVP Latched / Full Autorecovery /
Vout_UVP latched
Minimum operating frequency in VCO
200 Hz / 600 Hz / 1.2 kHz / 23 kHz
Frequency Clamp or Maximum operating
frequency
No Clamp / 80 kHz / 110 kHz
ORDERING TABLE OPTIONS
HV Startup
OPN #
NCP136_ _ _ _ _
6
1
Yes
No
NCP1366AABAY
X
NCP1366BABAY
X
NCP1366CABAY
X
NCP1366EABAY
X
Fault Mode
A
B
C
Min Operating Fsw (STBY)
E
Vcc_OVP
Full
Vout_UVP VOVP=3.6V
Latched Autorecovery Latched VUVP=0.75V
A
B
C
D*
E**
A
B
C
200 Hz
600 Hz
1.2 kHz
23 kHz
No min
No
80 kHz
110 kHz
X
X
X
X
NCP1361AABAY
X
NCP1361BABAY
X
NCP1361CABAY
X
NCP1361EABAY
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
* Min operating frequency D version is only available with fault Mode A & B.
** Min operating frequency E version is only available with fault Mode C.
www.onsemi.com
23
Frequency Clamp
NCP1361, NCP1366
ORDERING INFORMATION
Device
Marking
Package
Shipping†
NCP1366AABAYDR2G
1366A1
SOIC−7
(Pb−Free)
2500 / Tape & Reel
NCP1366BABAYDR2G
1366B1
SOIC−7
(Pb−Free)
2500 / Tape & Reel
NCP1361AABAYSNT1G
ADE
TSOP−6
(Pb−Free)
3000 / Tape & Reel
NCP1361BABAYSNT1G
ADF
TSOP−6
(Pb−Free)
3000 / Tape & Reel
NCP1361EABAYSNT1G
ACU
TSOP−6
(Pb−Free)
3000 / Tape & Reel
†For information on tape and reel specifications, including part orientation and tape sizes, please refer to our Tape and Reel Packaging
Specifications Brochure, BRD8011/D.
www.onsemi.com
24
NCP1361, NCP1366
PACKAGE DIMENSIONS
SOIC−7
CASE 751U
ISSUE E
−A−
8
NOTES:
1. DIMENSIONING AND TOLERANCING PER
ANSI Y14.5M, 1982.
2. CONTROLLING DIMENSION: MILLIMETER.
3. DIMENSION A AND B ARE DATUMS AND T
IS A DATUM SURFACE.
4. DIMENSION A AND B DO NOT INCLUDE
MOLD PROTRUSION.
5. MAXIMUM MOLD PROTRUSION 0.15 (0.006)
PER SIDE.
5
−B− S
0.25 (0.010)
B
M
M
1
4
DIM
A
B
C
D
G
H
J
K
M
N
S
G
C
R
X 45 _
J
−T−
SEATING
PLANE
H
0.25 (0.010)
K
M
D 7 PL
M
T B
S
A
S
SOLDERING FOOTPRINT*
1.52
0.060
7.0
0.275
4.0
0.155
0.6
0.024
1.270
0.050
SCALE 6:1
mm Ǔ
ǒinches
*For additional information on our Pb−Free strategy and soldering
details, please download the ON Semiconductor Soldering and
Mounting Techniques Reference Manual, SOLDERRM/D.
www.onsemi.com
25
MILLIMETERS
MIN
MAX
4.80
5.00
3.80
4.00
1.35
1.75
0.33
0.51
1.27 BSC
0.10
0.25
0.19
0.25
0.40
1.27
0_
8_
0.25
0.50
5.80
6.20
INCHES
MIN MAX
0.189 0.197
0.150 0.157
0.053 0.069
0.013 0.020
0.050 BSC
0.004 0.010
0.007 0.010
0.016 0.050
0_
8_
0.010 0.020
0.228 0.244
NCP1361, NCP1366
PACKAGE DIMENSIONS
TSOP−6
CASE 318G−02
ISSUE U
D
H
ÉÉÉ
ÉÉÉ
6
E1
1
NOTE 5
5
2
4
L2
GAUGE
PLANE
E
3
L
M
b
SEATING
PLANE
DETAIL Z
e
0.05
C
A
c
A1
DETAIL Z
NOTES:
1. DIMENSIONING AND TOLERANCING PER ASME Y14.5M, 1994.
2. CONTROLLING DIMENSION: MILLIMETERS.
3. MAXIMUM LEAD THICKNESS INCLUDES LEAD FINISH. MINIMUM
LEAD THICKNESS IS THE MINIMUM THICKNESS OF BASE MATERIAL.
4. DIMENSIONS D AND E1 DO NOT INCLUDE MOLD FLASH,
PROTRUSIONS, OR GATE BURRS. MOLD FLASH, PROTRUSIONS, OR
GATE BURRS SHALL NOT EXCEED 0.15 PER SIDE. DIMENSIONS D
AND E1 ARE DETERMINED AT DATUM H.
5. PIN ONE INDICATOR MUST BE LOCATED IN THE INDICATED ZONE.
DIM
A
A1
b
c
D
E
E1
e
L
L2
M
RECOMMENDED
SOLDERING FOOTPRINT*
MIN
0.90
0.01
0.25
0.10
2.90
2.50
1.30
0.85
0.20
MILLIMETERS
NOM
MAX
1.00
1.10
0.06
0.10
0.38
0.50
0.18
0.26
3.00
3.10
2.75
3.00
1.50
1.70
0.95
1.05
0.40
0.60
0.25 BSC
−
10°
0°
6X
0.60
6X
3.20
0.95
0.95
PITCH
DIMENSIONS: MILLIMETERS
*For additional information on our Pb−Free strategy and soldering
details, please download the ON Semiconductor Soldering and
Mounting Techniques Reference Manual, SOLDERRM/D.
ON Semiconductor and the
are registered trademarks of Semiconductor Components Industries, LLC (SCILLC) or its subsidiaries in the United States and/or other countries.
SCILLC owns the rights to a number of patents, trademarks, copyrights, trade secrets, and other intellectual property. A listing of SCILLC’s product/patent coverage may be accessed
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or guarantee regarding the suitability of its products for any particular purpose, nor does SCILLC assume any liability arising out of the application or use of any product or circuit, and
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PUBLICATION ORDERING INFORMATION
LITERATURE FULFILLMENT:
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26
ON Semiconductor Website: www.onsemi.com
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For additional information, please contact your local
Sales Representative
NCP1361/D