© Semiconductor Components Industries, LLC, 2014
September, 2014 − Rev. 11
1 Publication Order Number:
NCP1030/D
NCP1030, NCP1031
Low Power PWM Controller
with On-Chip Power Switch
and Startup Circuits for
48V Telecom Systems
The NCP1030 and NCP1031 are a family of miniature high−voltage
monolithic switching regulators with on−chip Power Switch and Startup
Circuits. The NCP103x family incorporates in a single IC all the active
power, control logic and protection circuitry required to implement, with
minimal external components, several switching regulator applications,
such as a secondary side bias supply or a low power dc−dc converter.
This controller family is ideally suited for 48 V telecom, 42 V automotive
and 12 V input applications. The NCP103x can be configured in any
single−ended topology such as forward or flyback. The NCP1030 is
targeted for applications requiring up to 3 W, and the NCP1031 is
targeted for applications requiring up to 6 W.
The internal error amplifier allows the NCP103x family to be easily
configured for secondary or primary side regulation operation in
isolated and non−isolated configurations. The fixed frequency oscillator
is optimized for operation up to 1 MHz and is capable of external
frequency synchronization, providing additional design flexibility. In
addition, the NCP103x incorporates individual line undervoltage and
overvoltage detectors, cycle by cycle current limit and thermal
shutdown to protect the controller under fault conditions. The preset
current limit thresholds eliminate the need for external sensing
components.
Features
On Chip High 200 V Power Switch Circuit and Startup Circuit
Internal Startup Regulator with Auxiliary Winding Override
Operation up to 1 MHz
External Frequency Synchronization Capability
Frequency Fold−down Under Fault Conditions
Trimmed ±2% Internal Reference
Line Undervoltage and Overvoltage Detectors
Cycle by Cycle Current Limit Using SENSEFET
®
Active LEB Circuit
Overtemperature Protection
Internal Error Amplifier
Pb−Free Packages are Available
Typical Applications
POE (Power Over Ethernet)/PD. Refer to Application Note AND8247.
Secondary Side Bias Supply for Isolated dc−dc Converters
Stand Alone Low Power dc−dc Converter
Low Power Bias Supply
Low Power Boost Converter
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SO−8
D SUFFIX
CASE 751
MARKING
DIAGRAMS
A = Assembly Location
L = Wafer Lot
Y = Year
W = Work Week
G = Pb−Free Package
Micro8t
DM SUFFIX
CASE 846A
1030
AYWG
G
8
1
8
1
1
GND
2
C
T
3
V
FB
4
COMP
V
CC
V
DRAIN
OV
UV
8
7
6
5
(Top View)
PIN CONNECTIONS
8
1
N1031
ALYW
G
1
8
(Note: Microdot may be in either location)
See detailed ordering and shipping information in the package
dimensions section on page 19 of this data sheet.
ORDERING INFORMATION
DFN−8
MN SUFFIX
CASE 488AF
NCP
1031
ALYW G
G
(Top View)
EP Flag
GND
C
T
V
FB
COMP
V
CC
V
DRAIN
OV
UV
1
NCP1030, NCP1031
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2
Figure 1. NCP1030/31 Functional Block Diagram
Thermal
Shutdown
One Shot
Pulse
IO
+
Reset
Dominant
Latch
S
R
+
+
+
+
7.5 V/10 V
10 V
6.5 V
2.5 V
+
LEB
Reset
Dominant
Latch
SQ
R
50 mV
+
+
+
+
2.5 V
+
Internal Bias
16 V
10 V
10 V
10 V
10 V
GND
VFB
COMP
UV
OV
Disable
3.0 V/3.5 V
+
PWM Latch
PWM Comparator
Error Amplifier
Current Limit
Comparator
V
DRAI
N
R
SENSE
10 V
V
CC
C
T
I
1
I
2
= 3I
1
Q
C
T
Ramp
+
+
2 kW
4.5 V
I
START
FUNCTIONAL PIN DESCRIPTION
Pin Name Function Description
1 GND Ground Ground reference pin for the circuit.
2 C
T
Oscillator Frequency
Selection
An external capacitor connected to this pin sets the oscillator frequency up to 1 MHz.
The oscillator can be synchronized to a higher frequency by charging or discharging
C
T
to trip the internal 3.0 V/3.5 V comparator. If a fault condition exists, the power
switch is disabled and the frequency is reduced by a factor of 7.
3 V
FB
Feedback Input The regulated voltage is scaled down to 2.5 V by means of a resistor divider.
Regulation is achieved by comparing the scaled voltage to an internal 2.5 V reference.
4 COMP Error Amplifier Compensation Requires external compensation network between COMP and V
FB
pins. This pin is
effectively grounded if faults are present.
5 OV Line Overvoltage Shutdown Line voltage (V
in
) is scaled down using an external resistor divider such that the OV
voltage reaches 2.5 V when line voltage reaches its maximum operating voltage.
6 UV Line Undervoltage Shutdown Line voltage is scaled down using an external resistor divider such that the UV
voltage reaches 2.5 V when line voltage reaches its minimum operating voltage.
7 V
CC
Supply Voltage This pin is connected to an external capacitor for energy storage. During Turn−On, the
startup circuit sources current to charge the capacitor connected to this pin. When the
supply voltage reaches V
CC(on)
, the startup circuit turns OFF and the power switch is
enabled if no faults are present. An external winding is used to supply power after
initial startup to reduce power dissipation. V
CC
should not exceed 16 V.
8 V
DRAIN
Power Switch and
Startup Circuits
This pin directly connects the Power Switch and Startup Circuits to one of the
transformer windings. The internal High Voltage Power Switch Circuit is connected
between this pin and ground. V
DRAIN
should not exceed 200 V.
NCP1030, NCP1031
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3
Figure 2. Pulse Width Modulation Timing Diagram
C
T
Ramp
C
T
Charge
Signal
PWM
Comparator
Output
PWM Latch
Output
Power Switch
Circuit Gate Drive
Leading Edge
Blanking Output
COMP Voltage
Current Limit
Propagation Delay
Current Limit
Threshold
Normal PWM Operating Range Output Overload
Figure 3. Auxiliary Winding Operation with Output Overload Timing Diagram
V
CC(on)
V
CC(off)
V
CC(reset)
0 V
0 mA
I
START
0 V
0 V
V
DRAIN
V
FB
Normal Operation
Power−up &
standby Operation
Output Overload
2.5 V
V
UV
0 V
3.0 V

NCP1031DR2

Mfr. #:
Manufacturer:
ON Semiconductor
Description:
IC CTRLR PWM OTP OVD HV 8SOIC
Lifecycle:
New from this manufacturer.
Delivery:
DHL FedEx Ups TNT EMS
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