A6271是DC-DC转换器控制器，提供可编程恒流输出，用于串联驱动大功率LED。控制器基于可编程固定频率，峰值电流模式控制架构。DC-DC转换器可以在不同的交换配置中配置，包括升压，降压 - 升压和降压（接地开关）。
The A6271 provides a cost-effective solution using an external logic-level MOSFET and minimum additional external components. The maximum LED current is set with a single external sense resistor and can be accurately modulated using a current reference input (analog control). External PWM dimming is possible via the PWMIN input, which also provides a shutdown mode. As an alternative, an internal PWM dimming circuit can be used by programming the PWMIN and DR pins. Either PWM scheme controls the PWMOUT output which drives an external p-channel MOSFET connected in series with the LED string. This MOSFET is also used to isolate the load during certain fault conditions, including output shorts to ground.
A6271经过精心设计，可通过分布解耦和用于EMI规范CISPR 25配置的外部可编程频率抖动电路来最小化电磁排放。还可以在大多数EMI标准开始的情况下，将基本开关频率编程为低于150 kHz。
A6271一组全面的整合公关otection features to protect the IC, the LED driver system, and the LED string against faults. Fixed-output overvoltage protection ensures no maximum voltage rating violations, even under a single point failure of the programmable-output overvoltage protection circuit. Other protection features include: LED overload (boost), output undervoltage (buck or buck-boost), input supply (VIN) undervoltage, 5 V Regulator (VREG) output undervoltage, high-side supply (PWM PMOS) undervoltage, and thermal protection.
这些部件在生产中，但已被确定为不适用于新设计。此分类表示此设备的销售目前仅限于现有客户应用程序。亚博尊贵会员该设备不应为新的设计应用程序购买，因为在不久的将来是可能的过时。亚博尊贵会员样品不再可用。
状态日期变更：2017年12月14日
推荐的替换：A6271-1
