产品说明
Housed in SO-8 or DIP-8 package, the NCP1200 represents a major leap toward ultra-compact Switch-Mode Power Supplies. Thanks to a novel concept, the circuit allows the implementation of a complete offline battery charger or a standby SMPS with few external components. Furthermore, an integrated output short-circuit protection lets the designer build an extremely low-cost AC/DC wall adapter associated with a simplified feedback scheme.
With an internal structure operating at a fixed 40 kHz, 60 kHz or 100 kHz, the controller drives low gate-charge switching devices like an IGBT or a MOSFET thus requiring a very small operating power. Thanks to current-mode control, the NCP1200 drastically simplifies the design of reliable and cheap offline converters with excellent audio- susceptibility and inherent pulse-by-pulse control.
When the current setpoint falls below a given value, e.g. the output power demand diminishes, the IC automatically enters the so-called skip cycle mode and provides excellent efficiency at light loads. Because this occurs at low peak current, no acoustic noise takes place.
Finally, the IC is self-supplied from the DC rail, eliminating the need of an auxiliary winding. This feature ensures operation in presence of low output voltage or shorts.
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特性 |
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- No Auxiliary Winding Operation
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- Internal Output Short-Circuit Protection
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- Extremely Low No-Load Standby Power
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- Current-Mode with Skip-Cycle Capability
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- Internal Leading Edge Blanking
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- 250 mA Peak Current Source/Sink Capability
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- Internally Fixed Frequency at 40 kHz, 60 kHz and 100 kHz
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- Direct Optocoupler Connection
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- Built-in Frequency Jittering for Lower EMI
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- SPICE Models Available for TRANsient and AC Analysis
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- Internal Temperature Shutdown
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- Pb-Free Packages are Available
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应用 |
- AC/DC Adapters
- Offline Battery Chargers
- Auxiliary/Ancillary Power Supplies (USB, Appliances, TVs, etc.)
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For complete product information, see the
datasheet
