UC2914中文资料工作温度范围为 -40°C 至 85°C 的 5V 至 35V 热插拔控制器数据手册TI规格书

描述 Description

The UC3914 family of hot swap power managers provides complete power management, hot swap and fault handling capability. Integrating this part and a few external components, allows a board to be swapped in or out upon failure or system modification without removing power to the hardware, while maintaining the integrity of the powered system. Complementary output drivers and diodes have been integrated for use with external capacitors as a charge pump to ensure sufficient gate drive to the external N-channel MOSFET transistor for low RDS(on). All control and housekeeping functions are integrated and externally programmable and include the fault current level, maximum output sourcing current, maximum fault time and average power limiting of the external FET. The UC3914 features a duty ratio current limiting technique, which provides peak load capability while limiting the average power dissipation of the external pass transistor during fault conditions. The fault level is fixed at 50 mV with respect to VCC to minimize total dropout.

The fault current level is set with an external current sense resistor. The maximum allowable sourcing current is programmed by using a resistor divider from VCC to REF to set the voltage on IMAX. The maximum current level, when the output appears as a current source is (VVCC – VIMAX)/RSENSE.

This part is offered in both 18-pin DW wide-body (SOIC) and dual-in-line (DIL) packages.

When the output current is less than the fault level, the external output transistor remains switched on. When the output current exceeds the fault level, but is less than the maximum sourcing level programmed by IMAX, the output remains switched on, and the fault timer starts to charge CT, a timing capacitor. Once CT charges to 2.5 V, the output device is turned off and CT is slowly discharged. Once CT is discharged to 0.5 V, the device performs a retry and the output transistor is switched on again. The UC3914 offers two distinct reset modes. In one mode with LR left floating or held low, the device tries to reset itself repeatedly if a fault occurs as described above. In the second mode with LR held high, once a fault occurs, the output is latched off until either LR is toggled low, the part is shutdown then re-enabled using SD\\, or the power to the part is turned off and then on again.

特性 Features

• 5V to 35V Operation
• Precision Maximum Current Control
• Precision Fault Threshold
• Programmable Average Power Limiting
• Programmable Overcurrent Limit
• Shutdown Control
• Charge Pump for Low RDS(on) High-Side Drive
• Latch Reset Function Available
• Output Drive VGS Clamping
• Fault Output Indication
• 18 Pin DIL and SOIC Packages

简介

UC2914属于集成电路（IC）的热插拔控制器。由TI制造生产的UC2914热插拔控制器PMIC - 热插拔控制器是能提供电路内保护和控制功能的半导体，可允许带电情况下在电路中插入或拔除其他组件。热插拔控制器可用于计算机网络和通用电源系统，主要根据输出电流、受控通道数量等特性，以及自动重试、故障超时和保护等特殊功能进行区分。