ZHCSO21 may 2021 BQ25720
PRODUCTION DATA
- 1
- 1 特性
- 2 應用
- 3 說明
- 4 Revision History
- 5 Description (continued)
- 6 Device Comparison Table
- 7 Pin Configuration and Functions
- 8 Specifications
-
9 Detailed Description
- 9.1 Overview
- 9.2 Functional Block Diagram
- 9.3
Feature Description
- 9.3.1 Power-Up Sequence
- 9.3.2 Vmin Active Protection (VAP) with Battery only
- 9.3.3 Two-Level Battery Discharge Current Limit
- 9.3.4 Fast Role Swap Feature
- 9.3.5 CHRG_OK Indicator
- 9.3.6 Input and Charge Current Sensing
- 9.3.7 Input Voltage and Current Limit Setup
- 9.3.8 Battery Cell Configuration
- 9.3.9 Device HIZ State
- 9.3.10 USB On-The-Go (OTG)
- 9.3.11 Converter Operation
- 9.3.12 Inductance Detection Through IADPT Pin
- 9.3.13 Converter Compensation
- 9.3.14 Continuous Conduction Mode (CCM)
- 9.3.15 Pulse Frequency Modulation (PFM)
- 9.3.16 Switching Frequency and Dithering Feature
- 9.3.17 Current and Power Monitor
- 9.3.18 Input Source Dynamic Power Management
- 9.3.19 Input Current Optimizer (ICO)
- 9.3.20 Two-Level Adapter Current Limit (Peak Power Mode)
- 9.3.21 Processor Hot Indication
- 9.3.22
Device Protection
- 9.3.22.1 Watchdog Timer
- 9.3.22.2 Input Overvoltage Protection (ACOV)
- 9.3.22.3 Input Overcurrent Protection (ACOC)
- 9.3.22.4 System Overvoltage Protection (SYSOVP)
- 9.3.22.5 Battery Overvoltage Protection (BATOVP)
- 9.3.22.6 Battery Discharge Overcurrent Protection (BATOC)
- 9.3.22.7 Battery Short Protection (BATSP)
- 9.3.22.8 System Undervoltage Lockout (VSYS_UVP) and Hiccup Mode
- 9.3.22.9 Thermal Shutdown (TSHUT)
- 9.4 Device Functional Modes
- 9.5 Programming
- 9.6
Register Map
- 9.6.1 ChargeOption0 Register (SMBus address = 12h) [reset = E70Eh]
- 9.6.2 ChargeCurrent Register (SMBus address = 14h) [reset = 0000h]
- 9.6.3 ChargeVoltage Register (SMBus address = 15h) [reset value based on CELL_BATPRESZ pin setting]
- 9.6.4 ChargerStatus Register (SMBus address = 20h) [reset = 0000h]
- 9.6.5 ProchotStatus Register (SMBus address = 21h) [reset = B800h]
- 9.6.6 IIN_DPM Register With 10-mΩ Sense Resistor (SMBus address = 22h) [reset = 4100h]
- 9.6.7 ADCVBUS/PSYS Register (SMBus address = 23h)
- 9.6.8 ADCIBAT Register (SMBus address = 24h)
- 9.6.9 ADCIINCMPIN Register (SMBus address = 25h)
- 9.6.10 ADCVSYSVBAT Register (SMBus address = 26h)
- 9.6.11 ChargeOption1 Register (SMBus address = 30h) [reset = 3300h]
- 9.6.12 ChargeOption2 Register (SMBus address = 31h) [reset = 00B7]
- 9.6.13 ChargeOption3 Register (SMBus address = 32h) [reset = 0434h]
- 9.6.14 ProchotOption0 Register (SMBus address = 33h) [reset = 4A81h(2S~) 4A09(1S)]
- 9.6.15 ProchotOption1 Register (SMBus address = 34h) [reset = 41A0h]
- 9.6.16 ADCOption Register (SMBus address = 35h) [reset = 2000h]
- 9.6.17 ChargeOption4 Register (SMBus address = 36h) [reset = 0048h]
- 9.6.18 Vmin Active Protection Register (SMBus address = 37h) [reset = 006Ch(2s~4s)/0004h(1s)]
- 9.6.19 OTGVoltage Register (SMBus address = 3Bh) [reset = 09C4h]
- 9.6.20 OTGCurrent Register (SMBus address = 3Ch) [reset = 3C00h]
- 9.6.21 InputVoltage (VINDPM) Register (SMBus address = 3Dh) [reset = VBUS-1.28V]
- 9.6.22 VSYS_MIN Register (SMBus address = 3Eh) [reset value based on CELL_BATPRESZ pin setting]
- 9.6.23 IIN_HOST Register (SMBus address = 3Fh) [reset = 4100h]
- 9.6.24 ID Registers
- 10Application and Implementation
- 11Power Supply Recommendations
- 12Layout
- 13Device and Documentation Support
- 14Mechanical, Packaging, and Orderable Information
封裝選項
機械數(shù)據(jù) (封裝 | 引腳)
- RSN|32
散熱焊盤機械數(shù)據(jù) (封裝 | 引腳)
- RSN|32
訂購信息
10.2.2.1 ACP-ACN Input Filter
The BQ25720 has average current mode control. The input current sensing through ACP/ACN is critical to recover inductor current ripple. Parasitic inductance on board will generate high frequency ringing on ACP-ACN which overwhelms converter sensed inductor current information. It is also difficult to manage parasitic inductance created based on different PCB layout. Larger parasitic inductance will generate larger sense current ringing which could cause the average current control loop to go into oscillation. Therefore ACP-ACN sensing information need to be conditioned.
For real system board condition, we suggest using below circuit design to get best result and filter noise induced from different PCB parasitic factor. With time constant of filter from 47 ns to 200 ns, the filter is effective and the delay of on the sensed signal is small, therefore there is no concern for average current mode control.
Figure 10-2 ACN-ACP Input Filter