ZHCSHF4J May 2004 – January 2018 TPS51116
PRODUCTION DATA.
- 1 特性
- 2 应用
- 3 说明
- 4 修订历史记录
- 5 Pin Configuration and Functions
- 6 Specifications
-
7 Detailed Description
- 7.1 Overview
- 7.2 Functional Block Diagram
- 7.3
Feature Description
- 7.3.1 VDDQ SMPS, Light Load Condition
- 7.3.2 Low-Side Driver
- 7.3.3 High-Side Driver
- 7.3.4 Current Sensing Scheme
- 7.3.5 PWM Frequency and Adaptive On-Time Control
- 7.3.6 VDDQ Output Voltage Selection
- 7.3.7 VTT Linear Regulator and VTTREF
- 7.3.8 Controling Outputs Using the S3 and S5 Pins
- 7.3.9 Soft-Start Function and Powergood Status
- 7.3.10 VDDQ and VTT Discharge Control
- 7.3.11 Current Protection for VDDQ
- 7.3.12 Current Protection for VTT
- 7.3.13 Overvoltage and Undervoltage Protection for VDDQ
- 7.3.14 Undervoltage Lockout (UVLO) Protection, V5IN (PWP), V5FILT (RGE)
- 7.3.15 Input Capacitor, V5IN (PWP), V5FILT (RGE)
- 7.3.16 Thermal Shutdown
- 7.4 Device Functional Modes
- 8 Application and Implementation
- 9 Power Supply Recommendations
- 10Layout
- 11器件和文档支持
- 12机械、封装和可订购信息
封装选项
请参考 PDF 数据表获取器件具体的封装图。
机械数据 (封装 | 引脚)
- RGE|24
- PWP|20
散热焊盘机械数据 (封装 | 引脚)
订购信息
7.3.11 Current Protection for VDDQ
The SMPS has cycle-by-cycle overcurrent limiting control. The inductor current is monitored during the OFF state and the controller keeps the OFF state during the inductor current is larger than the overcurrent trip level. The trip level and current sense scheme are determined by CS pin connection (see Current Sensing Scheme section). For resistor sensing scheme, the trip level, VTRIP, is fixed value of 60 mV.
For RDS(on) sensing scheme, CS terminal sinks 10 μA and the trip level is set to the voltage across this RTRIP resistor.
As the comparison is done during the OFF state, VTRIP sets valley level of the inductor current. Thus, the load current at overcurrent threshold, IOCP, can be calculated as shown in Equation 5.
In an overcurrent condition, the current to the load exceeds the current to the output capacitor thus the output voltage tends to fall down. If the output voltage becomes less than Powergood level, the VTRIP is cut into half and the output voltage tends to be even lower. Eventually, it crosses the undervoltage protection threshold and shutdown.