The UC3572 is a negative output flyback pulse width modulator which converts a positive input voltage to a regulated negative output voltage. The chip is optimized for use in a single inductor negative flyback switching converter employing an external PMOS switch. The block diagram consists of a precision reference, an error amplifier configured for voltage mode operation, an oscillator, a PWM comparator with latching logic, and a 0.5A peak gate driver. The UC3572 includes an undervoltage lockout circuit to insure sufficient input supply voltage is present before any switching activity can occur, and a pulse-by-pulse current limit. Output current can be sensed and limited to a user determined maximum value. The UVLO circuit turns the chip off when the input voltage is below the UVLO threshold. In addition, a sleep comparator interfaces to the UVLO circuit to turn the chip off. This reduces the supply current to only 50uA, making the UC3572 ideal for battery powered applications.

• Simple Single Inductor Flyback PWM for Negative Voltage Generation
• Drives External PMOS Switch
• Contains UVLO Circuit
• Includes Pulse-by-Pulse Current Limit
• Low 50uA Sleep Mode Current

• Vin (Min) (V)
• 4.2
• Vin (Max) (V)
• 35
• Vout (Min) (V)
• -70
• Vout (Max) (V)
• -1
• Regulated outputs (#)
• 1
• Switching frequency (Min) (kHz)
• 10
• Switching frequency (Max) (kHz)
• 200
• Iq (Typ) (mA)
• 9
• Features
• UVLO Fixed
• Duty cycle (Max) (%)
• 100
• Rating
• Catalog

UC2572的完整型号有：UC2572D、UC2572DTR，以下是这些产品的关键参数及官网采购报价：

UC2572D，工作温度：-40 to 85，封装：SOIC (D)-8，包装数量MPQ：75个，MSL 等级/回流焊峰值温度：Level-1-260C-UNLIM，引脚镀层/焊球材料：NIPDAU，TI官网UC2572D的批量USD价格：1.577（1000+）

UC2572DTR，工作温度：-40 to 85，封装：SOIC (D)-8，包装数量MPQ：2500个，MSL 等级/回流焊峰值温度：Level-1-260C-UNLIM，引脚镀层/焊球材料：NIPDAU，TI官网UC2572DTR的批量USD价格：1.343（1000+）

PSPICE-FOR-TI — 适用于 TI 设计和模拟工具的 PSpice

PSpice for TI 可提供帮助评估模拟电路功能的设计和仿真环境。此功能齐全的设计和仿真套件使用 Cadence 的模拟分析引擎。PSpice for TI 可免费使用，包括业内超大的模型库之一，涵盖我们的模拟和电源产品系列以及精选的模拟行为模型。

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在?PSpice for TI 设计和仿真工具中，您可以搜索 TI (...)

FLYBUCK-FLYBACK-DESIGN-CALC — Fly-Buck 和反激式拓扑选择器

该工具可帮助电源工程师基于规格选择正确的隔离式直流-直流拓扑。根据所选择的拓扑，计算器还会针对设计建议正确的 IC。