MPS MP171GS 700 v non-isolated off-line regulator up to 60 ma output current Datasheet

MP171
700 V Non-Isolated Off-Line Regulator
Up to 60 mA Output Current
The Future of Analog IC Technology
DESCRIPTION
FEATURES
MP171 is a primary-side regulator that provides
accurate constant voltage (CV) regulation
without an opto-coupler. It supports buck, boost,
buck-boost, and flyback topologies. It has an
integrated 700 V MOSFET to simplify the
structure and reduce cost. These features make
it an ideal regulator for offline low-power
applications, such as home appliances and
standby power.
MP171 is a green-mode-operation regulator.
Both the peak current and switching frequency
decrease as the load decreases. This feature
provides excellent efficiency at light load and
improves the overall average efficiency.
MP171 has various protection features
including thermal shutdown (TSD), VCC undervoltage lockout (UVLO), overload protection
(OLP), short-circuit protection (SCP), and openloop protection.
MP171 is available in a small TSOT23-5
package and SOIC-8 package.












Primary-Side CV Control, Supporting Buck,
Boost, Buck-Boost, and Flyback Topologies
Integrated 700 V MOSFET and Current
Source
< 30 mW No-Load Power Consumption
Up to 2 W Output Power
Maximum DCM Output Current Less than
40 mA
Maximum CCM Output Current Less than
60 mA
Low VCC Operating Current
Frequency Foldback
Limited Maximum Frequency
Peak Current Compression
Internally Biased VCC
TSD, UVLO, OLP, SCP, Open-Loop
Protection
APPLICATIONS



Home Appliances, White Goods, and
Consumer Electronics
Industrial Controls
Standby Power
All MPS parts are lead-free, halogen-free, and adhere to the RoHS directive. For
MPS green status, please visit the MPS website under Quality Assurance. “MPS”
and “The Future of Analog IC Technology” are registered trademarks of
Monolithic Power Systems, Inc.
TYPICAL APPLICATION
DRAIN
L
D2
VCC
C2
MP171
FB
R1
C3
R2
SOURCE
Input
SOURCE
VOUT
D1
N
MP171 Rev. 1.0
9/30/2015
L1
C1
C4
GND
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1
MP171 –NON-ISOLATED OFFLINE REGULATOR
ORDERING INFORMATION
Part Number
Package
Top Marking
MP171GJ*
MP171GS**
TSOT23-5
SOIC-8
See Below
See Below
* For Tape & Reel, add suffix –Z (e.g. MP171GJ–Z).
** For Tape & Reel, add suffix –Z (e.g. MP171GS–Z).
TOP MARKING(TSOT23-5)
APL: product code of MP171GJ;
Y: year code;
TOP MARKING (SOIC-8)
MP171: part number;
LLLLLLLL: lot number;
MPS: MPS prefix:
Y: year code;
WW: week code:
PACKAGE REFERENCE
TOP VIEW
VCC
1
FB
2
SOURCE
3
5
DRAIN
8 NC
VCC 1
FB 2
4
TSOT23-5
MP171 Rev. 1.0
9/30/2015
TOP VIEW
SOURCE
7 DRAIN
SOURCE 3
6 NC
SOURCE 4
5 NC
SOIC-8
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2
MP171 –NON-ISOLATED OFFLINE REGULATOR
ABSOLUTE MAXIMUM RATINGS (1)
Thermal Resistance
DRAIN to SOURCE (TJ = +25°C)-0.3 V to 700 V
All other pins ................................-0.3 V to 6.5 V
(2)
Continuous power dissipation .....(TA = +25°C)
TSOT23-5 .................................................... 1 W
SOIC-8 ......................................................... 1 W
Junction temperature ................................150°C
Lead temperature .....................................260°C
Storage temperature ................ -60°C to +150°C
TSOT23-5.............................. 100 ..... 55... °C/W
SOIC-8.................................... 96 ...... 45... °C/W
Recommended Operating Conditions
(3)
Operating junction temp (TJ). ... -40°C to +125°C
Operating VCC range ...................5.5 V to 5.7 V
MP171 Rev. 1.0
9/30/2015
(4)
θJA
θJC
NOTES:
1) Exceeding these ratings may damage the device.
2) The maximum allowable power dissipation is a function of the
maximum junction temperature TJ(MAX), the junction-toambient thermal resistance θJA, and the ambient temperature
TA. The maximum allowance continuous power dissipation at
any ambient temperature is calculated by PD(MAX)=(TJ(MAX)TA)/θJA. Exceeding the maximum allowance power dissipation
will produce an excessive die temperature, causing the
regulator to go into thermal shutdown. Internal thermal
shutdown circuit protects the device from permanent damage.
3) The device is not guaranteed to function outside of its
operating conditions.
4) Measured on JESD51-7, 4-layer PCB.
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3
MP171 –NON-ISOLATED OFFLINE REGULATOR
ELECTRICAL CHARACTERISTICS
VCC = 5.5 V, TJ = -40°C~125°C, min and max are guaranteed by characterization, typical is tested
under 25°C, unless otherwise specified.
Parameter
Symbol Condition
Start-up Current Source and Internal MOSFET (DRAIN)
Internal regulator supply current
Iregulator VCC = 4 V; VDrain = 100 V
DRAIN leakage current
ILeak
VCC = 5.8 V; VDrain = 400 V
V(BR)DSS TJ = 25°C
Breakdown voltage
On resistance
Ron
TJ = 25°C
Supply Voltage Management (VCC)
VCC level (increasing) where the internal
VCCOFF
regulator stops
VCC level (decreasing) where the
VCCON
internal regulator turns on
VCC regulator on and off hysteresis
VCC level (decreasing) where the IC
VCCstop
stops
VCC level (decreasing) where the
VCCpro
protection phase ends
Internal IC consumption
ICC
Internal IC consumption (no switching)
Internal IC consumption, latch-off phase
Internal Current Sense
Peak current limit
Min
Typ
Max
Units
2.2
4.1
10
6
17
mA
μA
700
20
25
Ω
5.4
5.7
6
V
5.1
5.5
5.8
V
130
250
3
3.4
3.6
V
2
2.5
2.8
V
720
μA
16
200
24
µA
μA
105
125
mA
fs = 36 kHz, D = 64%
ICC
ICCLATCH VCC = 5.3 V
ILimit
TJ = 25°C
85
τLEB1
Leading-edge blanking
SCP threshold
ISCP
Leading-edge blanking for SCP
(1)
V
mV
350
TJ = 25°C
220
τLEB2
300
ns
400
180
mA
ns
Feedback Input (FB)
Minimum off time
Maximum on time
Primary MOSFET feedback turn-on
threshold
OLP feedback trigger threshold
τminoff
τmanon
7.5
10
12.5
μs
13
18
23
μs
VFB
2.45
2.55
2.65
V
VFB_OLP
1.64
1.74
1.84
V
OLP delay time
τOLP
Open-loop detection
Thermal Shutdown
VOLD
Thermal shutdown threshold
(1)
Thermal shutdown recovery hysteresis
(1)
fs = 36 kHz
175
0.4
0.5
ms
0.6
V
150
°C
30
°C
NOTE:
1) This parameter is guaranteed by design.
MP171 Rev. 1.0
9/30/2015
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4
MP171 –NON-ISOLATED OFFLINE REGULATOR
TYPICAL CHARACTERISTICS
5.73
2.56
5.72
2.55
5.71
2.54
5.70
2.53
710
-40 -25-10 5 20 35 50 65 80 95 110125
5.69
-40 -25-10 5 20 35 50 65 80 95 110125
2.52
-40 -25-10 5 20 35 50 65 80 95 110125
5.50
2.60
1.8
2.55
1.6
810
800
790
780
770
760
750
740
730
720
5.49
5.48
2.50
5.47
2.45
5.46
5.45
2.40
5.44
5.43
5.42
-40 -25-10 5 20 35 50 65 80 95 110125
1.4
1.2
1.0
0.8
2.35
0.6
2.30
-40 -25-10 5 20 35 50 65 80 95 110125
0.4
-40 -25-10 5 20 35 50 65 80 95 110125
108.0
310
10.0
106.0
305
9.9
104.0
300
9.8
102.0
295
9.7
100.0
290
9.6
98.0
285
9.5
96.0
-40 -25-10 5 20 35 50 65 80 95 110125
280
-40 -25-10 5 20 35 50 65 80 95 110125
9.4
-40 -25-10 5 20 35 50 65 80 95 110125
MP171 Rev. 1.0
9/30/2015
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5
MP171 –NON-ISOLATED OFFLINE REGULATOR
TYPICAL PERFORMANCE CHARACTERISTICS
VIN = 230 VAC, VOUT = 5 V, IOUT = 50 mA, L = 1 mH, COUT = 22 μF, TA = +25°C, unless otherwise
noted.
VDS
100V/div.
VDS
100V/div.
VDS
100V/div.
IL
100mA/div.
IL
100mA/div.
IL
100mA/div.
VDS
100V/div.
VDS
100V/div.
VDS
100V/div.
IL
200mA/div.
IL
100mA/div.
IL
100mA/div.
VDS
100V/div.
VRIPPLE
50mV/div.
VRIPPLE
50mV/div.
IL
200mA/div.
MP171 Rev. 1.0
9/30/2015
IOUT
50mA/div.
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6
MP171 –NON-ISOLATED OFFLINE REGULATOR
PIN FUNCTIONS
Pin #
TSOT23-5
1
2
3,4
5
MP171 Rev. 1.0
9/30/2015
Pin #
SOIC8
1
2
3,4
7
5,6,8
Name
VCC
FB
SOURCE
DRAIN
NC
Description
Control circuit power supply.
Regulator feedback.
Internal power MOSFET source and ground reference for VCC and FB.
Internal power MOSFET drain and high-voltage current source input.
No connection.
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MP171 –NON-ISOLATED OFFLINE REGULATOR
FUNCTIONAL BLOCK DIAGRAM
VCC
DRAIN
Start-Up Unit
Power
Management
Driving Signal
Management
Feedback Control
Peak Current
Limitation
FB
Protection Unit
SOURCE
Figure 1—Functional block diagram
MP171 Rev. 1.0
9/30/2015
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MP171 –NON-ISOLATED OFFLINE REGULATOR
OPERATION
MP171 is a green-mode-operation regulator: The
peak current and the switching frequency both
decrease with a decreasing load. As a result, it
offers excellent light-load efficiency and improves
overall average efficiency. Also, the regulator
incorporates multiple features and operates with
a minimal number of external components.
The MP171 acts as a fully integrated regulator
when used in buck topology (see Typical
Application on page 1).
Start-Up and Under-Voltage Lockout
The internal high-voltage regulator self-supplies
the IC from DRAIN. When VCC voltage reaches
VCCOFF, the IC starts switching, and the internal
high-voltage regulator turns off. The internal highvoltage regulator turns on to charge the external
VCC capacitor when the VCC voltage falls below
VCCON. A small capacitor (in the low μF range)
maintains the VCC voltage and thus lowers the
capacitor cost.
The IC stops switching when the VCC voltage
drops blow VCCstop.
Under fault conditions—such as OLP, SCP, and
TSD—the IC stops switching, and an internal
current source (~16 μA) discharges the VCC
capacitor. The internal high-voltage regulator will
not charge the VCC capacitor until the VCC
voltage drops below VCCpro. The re-start time
can be estimated using Equation (1):
 48us
18 us
10 us
Driver
128 Switching cycle 128 Switching cycle
Figure 2— min off at start-up
Constant Voltage (CV) Operation
The MP171 regulates the output voltage by
monitoring the sampling capacitor.
At the beginning of each cycle, the integrated
MOSFET turns on while the feedback voltage
drops below the 2.55 V reference voltage, which
indicates insufficient output voltage. The peak
current limitation determines the on period. After
the on period elapses, the integrated MOSFET
turns off. The sampling capacitor (C3) voltage is
charged to the output voltage when the
freewheeling diode (D1) turns on. In his way, the
sampling capacitor (C3) samples and holds the
output voltage for output regulation. The
sampling capacitor (C3) voltage decreases when
the L1 inductor current falls below the output
current. When the feedback voltage falls below
the 2.55 V reference voltage, a new switching
cycle begins. Figure 3 shows this operation in
continuous conduction mode (CCM).
MOSFET
Diode
restart
 VCC  VCCpro VCCOFF  VCCpro
 C VCC  


ICCLATCH
Iregulator


 (1)

Soft Start (SS)
Ipeak
Io
Vo
The IC stops operation when the VCC voltage
drops below VCCstop; the IC begins operation
when VCC charges to VCCOFF. Every time the
chip starts operation there is a soft-start period.
The soft start prevents the inductor current from
overshooting by limiting the minimum off time.
MP171 adopts a 2 phase minimum off time limit
soft start. Each soft-start phase retains 128
switching cycles. During the soft start, the off
time limit gradually shortens from 48 μs to 18 μs
and finally reaches the normal operation off time
limit (see Figure 2).
MP171 Rev. 1.0
9/30/2015
IL
V FB
2.55V
Figure 3—VFB vs. VO
Equation (2) determines the output voltage:
Vo  2.55V 
R1  R2
R2
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(2)
9
MP171 –NON-ISOLATED OFFLINE REGULATOR
Frequency Foldback and Peak Current
Compression
The MP171 remains highly efficient at light-load
conditions by reducing the switching frequency
automatically.
Under light-load or no-load conditions, the output
voltage drops very slowly, which increases the
MOSFET off time. Thus, the frequency
decreases along with the load.
The switching frequency is determined with
Equation (3) and Equation (4):
fs 
(Vin  Vo ) Vo
, for CCM

2L(Ipeak  Io ) Vin
(3)
fs 
2(Vin  VO ) Io Vo
, for DCM

LI2peak
Vin
(4)
As the peak current limit decreases from 105 mA,
the off time increases. In standby mode, the
frequency and the peak current are both
minimized, allowing for a smaller dummy load. As
a result, peak current compression helps further
reduce no-load consumption. The peak current
limit can be estimated from Equation (5) where
τoff is the off time of the power module:
IPeak  105mA  (0.4mA / s)  ( off  10s)
(5)
FB
Comparator
+
EA
+
+
Vramp
+
Vramp
V
ref
2.55V
Ipeak
Figure 4—EA and ramp compensation
MP171 has an internal error amplifier (EA)
compensation loop. It samples the feedback
voltage 6 µs after the MOSFET turns off and
regulates the output based on the 2.55 V
reference voltage.
MP171 Rev. 1.0
9/30/2015
The maximum output power of the MP171 is
limited by the maximum switching frequency and
the peak current limit. If the load current is too
large, the output voltage drops, causing the FB
voltage to drop.
When the FB voltage drops below VFB_OLP, it is
considered an error flag, and the timer starts. If
the timer reaches 170 ms (fS = 36 kHz), OLP
occurs. This timer duration avoids triggering OLP
when the power supply starts up or the load
transitions. The power supply should start up in
less than 170 ms (fS = 36 kHz). The OLP delay
time is calculated using Equation (6):
Delay  170ms 
36kHz
fs
(6)
Thermal Shutdown (TSD)
M
+
-
Over-Load Protection (OLP)
Short-Circuit Protection (SCP)
The MP171 monitors the peak current and shuts
down when the peak current rises above the
SCP threshold through short-circuit protection.
The power supply resumes operation with the
removal of the fault.
EA Compensation
VFB
Ramp Compensation
An internal ramp compensation circuit improves
the load regulation. As shown in Figure 4, a
voltage sinking source is added to pull down the
reference voltage of the feedback comparator.
The ramp compensation is relative to the
MOSFET off time, and increases exponentially
as the off time increases. The compensation is
about 1mV/µs under min off time switching
condition.
To prevent thermal induced damage, the MP171
stops switching when the junction temperature
exceeds 150°C. During thermal shutdown (TSD),
the VCC capacitor is discharged to VCCpro, and
the the internal high-voltage regulator re-charges.
MP171 recovers when the junction temperature
drops below 120°C.
Open-Loop Detection
If VFB is less than 0.5 V, the IC stops switching,
and a re-start cycle begins. During a soft start,
the open-loop detection is blanked.
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10
MP171 –NON-ISOLATED OFFLINE REGULATOR
Leading-Edge Blanking
An internal leading-edge blanking (LEB) unit
avoids premature switching pulse termination
due to a turn-on spike. A turn-on spike is caused
by parasitic capacitance and reverse recovery of
the freewheeling diode. During the blanking time,
the current comparator is disabled and cannot
turn off the external MOSFET. Figure 5 shows
the leading-edge blanking.
IDS
350ns
ILIMIT
t
Figure 5—Leading-edge blanking
MP171 Rev. 1.0
9/30/2015
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MP171 –NON-ISOLATED OFFLINE REGULATOR
APPLICATION INFORMATION
Table 1—Common topologies using MP171
Topology
Circuit Schematic
DRAIN
5
1
MP171
High-side
buck
SOURCE
4
2
3
Features
VCC
FB
SOURCE
1.
2.
3.
4.
No isolation
Positive output
Low cost
Direct feedback
1.
2.
3.
4.
No isolation
Negative output
Low cost
Direct feedback
1.
2.
3.
4.
No isolation
Positive output
Low cost
Direct feedback
1.
2.
3.
4.
Isolation
Positive output
Low cost
Indirect feedback
Vin
Vo
DRAIN
1
5
MP171
High-side
buck-boost
SOURCE
2
3
4
VCC
FB
SOURCE
Vin
Vo
DRAIN
Boost
5
1
MP171
Vin
SOURCE
2
3
4
VCC
FB
Vo
SOURCE
T
*
Vin
*
Flyback
DRAIN
1
5
MP171
SOURCE
MP171 Rev. 1.0
9/30/2015
4
2
3
VCC
FB
SOURCE
*
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MP171 –NON-ISOLATED OFFLINE REGULATOR
Topology Options
MP171 can be used in common topologies such
as buck, boost, buck-boost, and flyback (see
Table 1).
Component selection below is based on the
typical application of MP173 (see it on page 1).
Component Selection
Input Capacitor
The input capacitor supplies the DC input voltage
for the converter. Figure 6 shows the typical DC
bus voltage waveform of a half-wave rectifier and
a full-wave rectifier.
Vin
VDC(max)
DC input voltage
VDC(min)
AC input voltage
t
Vin
VDC(max)
VDC( min)
maximum power using Equation (7) and Equation
(8):
V
(7)
Po max  Vo (Ipeak  o min off ) , for CCM
2L
1 2
1 , for DCM
(8)
Po max  LIpeak

2
min off
For mass production, tolerance on the
parameters (such as peak current limitation) and
the minimum off time should be taken into
consideration.
Freewheeling Diode
Select a diode with a maximum reverse-voltage
rating greater than the maximum input voltage
and a current rating determined by the output
current.
The reverse recovery of the freewheeling diode
affects efficiency and circuit operation during a
CCM condition, so use an ultra-fast diode such
as the EGC10JH.
Output Capacitor
DC input voltage
The output capacitor is required to maintain the
DC output voltage. Estimate the output voltage
ripple using Equation (9) and Equation (10):
AC input voltage
VCCM _ ripple 
t
Figure 6—Input voltage waveform
Typically, the use of a half-wave rectifier requires
an input capacitor rated at 3 µF/W for the
universal input condition. When using a full-wave
rectifier, an input capacitor is chosen between
1.5~2 µF/W for the universal input condition. A
half-wave rectifier is recommended for a < 2 W
output application, otherwise use a full-wave
rectifier.
Under very low input voltage, the inductor current
ramps up slowly; it may not reach the current
limit during τmanon, so the MOSFET maximum on
time should be less than the minimum value of
τmanon.
Inductor
The MP171 has a minimum off-time limit that
determines the maximum power output. A power
inductor with a larger inductance increases the
maximum power. Using a very small inductor
may cause failure at full load. Estimate the
MP171 Rev. 1.0
9/30/2015
VDCM _ ripple
i
 i  RESR , for
8fsCo
I
 o
fsCo
(9)
2
I I 
  pk o   Ipk  RESR , for DCM (10)
 I

 pk 
It is recommended to use ceramic, tantalum, or
low ESR electrolytic capacitors to reduce the
output voltage ripple.
Feedback Resistors
The resistor divider determines the output
voltage. Choose appropriate R1 and R2 values to
maintain VFB at 2.55 V. An excessively large
value for R2 should be avoided.
Sampling Capacitor
The sampling capacitor (C3) samples and holds
the output voltage for feedback. With R1 and R2
fixed, a small sampling capacitor result in poor
regulation at light loads, and large sampling
capacitor affect the circuit operation. Roughly
estimate an optimal capacitor value using
Equation (11):
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13
MP171 –NON-ISOLATED OFFLINE REGULATOR
C
Vo
C
1 Vo
 o  CFB 
 o
2 R1  R2 Io
R1  R2 Io
(11)
Dummy Load
A dummy load is required to maintain the load
regulation. This ensures there is sufficient
inductor energy to charge the sample and hold
capacitor to detect the output voltage. Normally,
a 3 mA dummy load is needed and can be
adjusted according to the regulated voltage.
There is a compromise between small, no-load
consumption and good, no-load regulation,
especially for applications that require 30 mW noload consumption. Use a Zener to reduce noload consumption if no-load regulation is not a
concern.
Auxiliary VCC Supply
MP171
SOURCE
R1
C3
L1
VOUT
Figure 7—Auxiliary VCC supply circuit
For applications with VO above 7 V, the MP171
achieves the 30 mW no-load power requirement
by adopting an external VCC supply to reduce
power consumption on the internal VCC regulator
(see Figure 7).
This auxiliary VCC supply is derived from the
resistor connected between C2 and C3. C3
should be set larger than the value
recommendation above. D3 is used in case VCC
interferes with FB. R3 is determined using
Equation (12):
R3 
Vo  VFW  5.8V
IS
(12)
Where IS is the VCC consumption under a noload condition, and VFW is the forward voltage
drop of D3. Because IS varies in different
applications, R3 should be adjusted to meet the
application’s specific IS. In a particular
configuration, IS is measured at about 200 µA.
MP171 Rev. 1.0
9/30/2015
FR1
L1
C1
C2
Figure 8—Half-wave rectifier
D2
R2
SOURCE
L
D3
VCC
C2
An appropriate input capacitor value should be
chosen to obtain good surge performance. Figure
8 shows the half-wave rectifier. Table 2 shows
the capacitance required under normal conditions
for different surge voltages. FR1 is a 20 Ω/2 W
fused resistor, and L1 is 1 mH for this
recommendation.
N
R3
FB
Surge Performance
Table 2—Recommended capacitance
Surge
500 V
1000 V
2000 V
Voltage
1 μF
2.2 μF
3.3 μF
C1
1 μF
2.2 μF
3.3 μF
C2
PCB Layout Guidelines
Efficient PCB layout is critical for reliable
operation, good EMI, and thermal performance.
For best results, follow the guidelines below:
1) Minimize the loop area formed by the input
capacitor, IC, freewheeling diode, inductor,
and output capacitor.
2) Place the power inductor far away from the
input filter while keeping the loop area to the
inductor at a minimum (see example below).
3) Place a capacitor valued at several hundred
pF between FB and SOURCE as close to the
IC as possible.
4) Connect the exposed pads or large copper
area with DRAIN to improve thermal
performance.
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MP171 –NON-ISOLATED OFFLINE REGULATOR
Top layer
Bottom layer
Design Example
Table 3 shows a design example for the following
application guideline specifications:
Table 3—Design example
85 VAC to 265 VAC
VIN
5V
VOUT
50 mA
IOUT
The detailed application schematic is shown in
Figure 9. The typical performance and circuit
waveforms have been shown in the “Typical
Performance Characteristics” section. For
additional device applications, please refer to the
related evaluation board datasheets.
MP171 Rev. 1.0
9/30/2015
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MP171 –NON-ISOLATED OFFLINE REGULATOR
TYPICAL APPLICATION CIRCUITS
Figure 9 shows a typical application example of a 5 V, 50 mA non-isolated power supply using the
MP171.
D1
R1
41.2 K
SRGC10JH
C1
22 nF
8
RF1
L
39
85 VAC~265VAC
NC
VCC
1
L1
D2
SRGC10JH
U1
7
1 mH
6
C3
C4
2.2 µF/400 V
2.2 µF/400 V
5
DRAIN
FB
2
NC
SOURC
E
3
NC
SOURC
E
4
C2
2.2 µF
C7
470 pF
R2
39.2 K
5 V/50 mA
L2
1 mH
Vout
MP171GS
D3
STTH1R06
600 V/1 A
C5
C6
R3
22 µF
NC
1.2 K
D4
N
SRJC10JH
GND
GND
Figure 9—Typical application at 5 V, 50 mA
MP171 Rev. 1.0
9/30/2015
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MP171 –NON-ISOLATED OFFLINE REGULATOR
FLOW CHART
Power On
Vcc Decrease
to VCCPRO
Internal High Voltage
Regulator On
Shut Down
Internal High Voltage
Regulator
Y
Y
N
VCC>VCCOFF
N
Soft Start
Shuts Down
Internal High Voltage
Regulator
VCC>VCCSTOP
Stop Operation
Y
Y
Fault Logic N
High?
Monitor VCC
Y
VCC>VCCOFF
N
VCC<VCCON
N
TSD, SCP
and Open-Loop
Monitor
Y
Internal High Voltage
Regulator On
Monitor FB Voltage
Open-Loop Logic High
N
< VFB
Y
Turn On the
MOSFET
< VFB_OLP
N
N
< VOLD
Y
Y
Counts to 6144
Switching
Cycle?
N
Y
OLP Fault
Logic High
Y
Count Switching
Cycle
OLP Fault
Logic High?
N
Reset Counter
UVLO, SCP, OLP, OTP and Open-Loop Protections are Auto Restart
Figure 10—Control flow chart
MP171 Rev. 1.0
9/30/2015
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MP171 –NON-ISOLATED OFFLINE REGULATOR
Normal
Operation
Start Up
16µA Discharge
Current
Unplug from
Main Input
VCCOFF
VCC
VCCON
VCCSTOP
VCCPRO
Start-Up
Blanking
Time
Driver
Pluses
Driver
Internal
Regulator
Supply
Current
On and Off
Fault Flag
Open-Loop Fault
Over-Load Over-Load
Fault
Fault
Counter<6144 Counter=6144
Short Circuit
Fault
Thermal Shutdown
Fault
Figure 11—Signal evolution in the presence of a fault
MP171 Rev. 1.0
9/30/2015
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MP171 –NON-ISOLATED OFFLINE REGULATOR
PACKAGE INFORMATION
TSOT23-5
0.95
BSC
0.60
TYP
2.80
3.00
5
4
1.20
TYP
1.50
1.70
1
2.60
3.00
2.60
TYP
3
TOP VIEW
RECOMMENDED LAND PATTERN
0.90
1.30
1.45 MAX
0.09
0.20
SEATING PLANE
0.30
0.50
0.95 BSC
0.00
0.15
SEE DETAIL "A"
FRONT VIEW
SIDE VIEW
NOTE:
GAUGE PLANE
0.25 BSC
0o-8o
0.30
0.55
DETAIL “A”
MP171 Rev. 1.0
9/30/2015
1) ALL DIMENSIONS ARE IN MILLIMETERS.
2) PACKAGE LENGTH DOES NOT INCLUDE MOLD FLASH,
PROTRUSION OR GATE BURR
.
3) PACKAGE WIDTH DOES NOT INCLUDE INTERLEAD FLASH
OR PROTRUSION
.
4) LEAD COPLANARITY (BOTTOM OF LEADS AFTER FORMING)
SHALL BE
0.10 MILLIMETERS MAX.
5) DRAWING CONFORMS TO JEDEC MO -178, VARIATION AA .
6) DRAWING IS NOT TO SCALE .
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MP171 –NON-ISOLATED OFFLINE REGULATOR
PACKAGE INFORMATION
SOIC-8
0.189(4.80)
0.197(5.00)
8
0.050(1.27)
0.024(0.61)
5
0.063(1.60)
0.150(3.80)
0.157(4.00)
PIN 1 ID
1
0.228(5.80)
0.244(6.20)
0.213(5.40)
4
TOP VIEW
RECOMMENDED LAND PATTERN
0.053(1.35)
0.069(1.75)
SEATING PLANE
0.004(0.10)
0.010(0.25)
0.013(0.33)
0.020(0.51)
0.0075(0.19)
0.0098(0.25)
SEE DETAIL "A"
0.050(1.27)
BSC
SIDE VIEW
FRONT VIEW
0.010(0.25)
x 45o
0.020(0.50)
GAUGE PLANE
0.010(0.25) BSC
0o-8o
0.016(0.41)
0.050(1.27)
DETAIL "A"
NOTE:
1) CONTROL DIMENSION IS IN INCHES. DIMENSION IN
BRACKET IS IN MILLIMETERS.
2) PACKAGE LENGTH DOES NOT INCLUDE MOLD FLASH
,
PROTRUSIONS OR GATE BURRS.
3) PACKAGE WIDTH DOES NOT INCLUDE INTERLEAD FLASH
OR PROTRUSIONS.
4) LEAD COPLANARITY(BOTTOM OF LEADS AFTER FORMING)
SHALL BE 0.004" INCHES MAX.
5) DRAWING CONFORMS TO JEDEC MS-012, VARIATION AA.
6) DRAWING IS NOT TO SCALE.
NOTICE: The information in this document is subject to change without notice. Users should warrant and guarantee that third
party Intellectual Property rights are not infringed upon when integrating MPS products into any application. MPS will not
assume any legal responsibility for any said applications.
MP171 Rev. 1.0
9/30/2015
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