NCP1207A ON Semiconductor, NCP1207A Datasheet
NCP1207A
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NCP1207A Summary of contents
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... PWM Current−Mode Controller for Free Running Quasi−Resonant Operation The NCP1207A combines a true current mode modulator and a demagnetization detector to ensure full borderline/critical Conduction Mode in any load/line conditions and minimum drain voltage switching (Quasi−Resonant operation). Due to its inherent skip cycle capability, the controller enters burst mode as soon as the power demand falls below a predetermined level ...
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... Driving pulses 6 V Supplies the High−voltage pin * + OVP and NCP1207A Demag Figure 1. Typical Application Á Á Á Á Á Á Á Á Á Á Á Á Á Á Á Á Á Á Function Á ...
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HV 7.0 PON mA + − 5.3 V (fault) To Internal Fault Supply Mngt. GND *S and R are level triggered whereas S is edge triggered. R has priority over the other inputs. ...
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MAXIMUM RATINGS Á Á Á Á Á ...
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ELECTRICAL CHARACTERISTICS unless otherwise noted) CC Rating DYNAMIC SELF−SUPPLY V Increasing Level at which the Current Source Turns−off CC V Decreasing Level at which the Current Source Turns− Decreasing Level at which the Latchoff ...
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TEMPERATURE (°C) Figure 3. Internal IC Consumption (No Output Load) versus Temperature 12.9 12.4 11.9 11.4 10.9 10.4 −50 − TEMPERATURE (°C) Figure 5. VCC ...
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TEMPERATURE (°C) Figure 9. Input Voltage (Vpin1 Decreasing) versus Temperature 8.0 7.8 7.6 7.4 7.2 7.0 6.8 6.6 6.4 6.2 6.0 −50 1.20 1.15 1.10 1.05 1.00 0.95 ...
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... Overcurrent Protection (OCP): by continuously monitoring the FB line activity, NCP1207A enters burst mode as soon as the power supply undergoes an technology, the overload. The device enters a safe low power operation which prevents from any lethal thermal runaway ...
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... IC consumption plus the above driving current (altered by the driver’s efficiency). Suppose that the IC is supplied from a 350 VDC line. The current flowing through pin direct image of the NCP1207A consumption (neglecting the switching losses of the HV current source equals 2 60° ...
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... The skip level selection is done through a simple resistor inserted between the current sense input and the sense element. Every time the NCP1207A output driver goes low, a 200 mA source forces a current to flow through the sense pin (Figure 15): when the driver is high, the current source is off and the current sense information is normally processed ...
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... Figure 20. A voltage sample is taken 4.5 ms after When an OVP condition has been detected, the NCP1207A enters a latchoff phase and stops all switching operations. The controller stays fully latched in this position and the DSS is still active, keeping the V V/ normal operations. This state lasts until the V ...
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... Several solutions exist to cure this trouble: • The first one consists in adding some copper area around the NCP1207A DIP8 footprint. By adding a min pad area 75°C/W. Maximum power then grows up to 730 mW. • A resistor R negative spikes at turn−off (see below) b) split the power budget between this resistor and the package ...
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... 5.3 V DRV INTERNAL FAULT FLAG STARTUP PHASE Soft−Start The NCP1207A features an internal 1 ms soft−start to soften the constraints occurring in the power supply during startup activated during the power on sequence. As soon as V reaches VCC , the peak current is gradually CC OFF increased from nearly zero up to the maximum clamping NCP1207A hosts a dedicated overload detection circuitry ...
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... NCP1207A, one instance can occur: A negative ringing can take place on pin8 due to a resonance between the primary inductance and the bulk capacitor. As any CMOS device, the NCP1207A is sensitive to negative voltages that could appear on it’s pins and could create an internal latch−up condition. ...
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V (5 V/div V/div) GATE Figure 27. The short−circuit protection forces the IC to enter burst in presence of a secondary overload. http://onsemi.com 15 ...
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... C SEATING PLANE −Z− 0.25 (0.010 *For additional information on our Pb−Free strategy and soldering details, please download the ON Semiconductor Soldering and Mounting Techniques Reference Manual, SOLDERRM/D. PACKAGE DIMENSIONS SOIC−8 NB CASE 751−07 ISSUE 0.10 (0.004) ...
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... G H 0.13 (0.005) The product described herein (NCP1207A), may be covered by one or more of the following U.S. patents: 6,362,067, 6,385,060, 6,385,061, 6,429,709, 6,587,357, 6,633,193. There may be other patents pending. ON Semiconductor and are registered trademarks of Semiconductor Components Industries, LLC (SCILLC). SCILLC reserves the right to make changes without further notice to any products herein ...