NCP1236: Fixed Frequency PWM Controller for Flyback Converters
The NCP1236 is a new fixed-frequency current-mode controller featuring Dynamic Self-Supply (DSS). This device is pin-to-pin compatible with the previous NCP12xx families. The DSS function greatly simplifies the design of the auxiliary supply and the VCC capacitor by activating the internal startup current source to supply the controller during transients. Due to frequency foldback, the controller exhibits excellent efficiency in light load condition while still achieving very low standby power consumption. Internal frequency jittering, ramp compensation, and a versatile latch input make this controller an excellent candidate for converters where component cost is the key constraint. In addition, the controller includes a new high voltage circuitry that combines a startup current source and a brown-out detector able to sense the input voltage either from the rectified ac line or the dc filtered bulk voltage. The high voltage sensing circuitry is used for the overpower protection purposes as well. Overpower protection, overload protection, and other protective features increase the safety and reliability of the final application.
技术特性
- Fixed−Frequency Current−Mode Operation with Built−In Ramp
Compensation
- 65 kHz or 100 kHz Oscillator Frequency
- Frequency Foldback then Skip Mode for Maximized Performance in
Light Load and Standby Conditions
- Timer−Based Overload Protection with Latched (option A) or
Auto−Recovery (option B) Operation, Shortened Overload Timer for
Increased Safety (options C and D), (see all options on page 2)
- High−voltage Current Source with Brown−Out
detection and Dynamic Self−Supply, Simplifying the
Design of the VCC Capacitor
- Frequency Modulation for Softened EMI Signature,
including during Frequency Foldback mode
- Adjustable Overpower Compensation
- Latch−off Input for Severe Fault Conditions, Allowing
Direct Connection of an NTC for Overtemperature
Protection (OTP)
- VCC Operation up to 28 V, with Overvoltage Detection
- 500 mA Peak Source / Sink Current Drive Capability
- 4.0 ms Soft−Start
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终端产品
- Notebooks
- LCD TVs
- Printers
应用
- AC-DC Adapters
- Consumer Electronics Power Supplies
- Auxiliary/Housekeeping power supplies
封装图 PACKAGE DIMENSIONS
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评估板信息
订购信息 Ordering Information
产品 |
状况 |
Compliance |
具体说明 |
封装 |
MSL* |
容器 |
预算价格 (1千个数量的单价) |
类型 |
外形 |
类型 |
数量 |
NCP1236AD100R2G |
Active |
|
Fixed Frequency PWM Controller for Flyback Converters |
SOIC-8 |
751U |
1 |
Tape and Reel |
2500 |
$0.3 |
NCP1236AD65R2G |
Active |
|
Fixed Frequency PWM Controller for Flyback Converters |
SOIC-8 |
751U |
1 |
Tape and Reel |
2500 |
$0.3 |
NCP1236BD100R2G |
Active |
|
Fixed Frequency PWM Controller for Flyback Converters |
SOIC-8 |
751U |
1 |
Tape and Reel |
2500 |
$0.3 |
NCP1236BD65R2G |
Active |
|
Fixed Frequency PWM Controller for Flyback Converters |
SOIC-8 |
751U |
1 |
Tape and Reel |
2500 |
$0.3 |
NCP1236DD65R2G |
Active |
|
Fixed Frequency PWM Controller for Flyback Converters |
SOIC-8 |
751U |
1 |
Tape and Reel |
2500 |
$0.3 |
数据资料DataSheet下载