RT9466

Part: RT9466 — Richtek Technology Corporation

Type: Single Cell Li-Ion Switching Battery Charger with Power Path Management and USB-OTG Boost Mode

Description: A 5A, 1.5MHz switch-mode single cell Li-Ion/Li-Polymer battery charger with integrated synchronous PWM controller, power MOSFETs, input current sensing, high-accuracy voltage regulation, charge termination, and USB On-The-Go (OTG) support.

Operating Conditions:

• Supply input voltage: 4V to 14V
• Junction temperature range: -40°C to 125°C
• Maximum input current (VBUS): 3.25A
• Maximum battery voltage: 4.71V

Absolute Maximum Ratings:

• Max supply input voltage, VBUS: 22V
• Max junction temperature: 150°C
• Max storage temperature: -65°C to 150°C

Key Specs:

• Charging efficiency: 90.25% at ICHG = 2A
• Synchronous PWM controller frequency: 1.5MHz/0.75MHz
• Average input current regulation (AICR) range: 0.1A to 3.25A in 50mA steps
• Charge voltage regulation accuracy: ±1% (0°C to 85°C)
• Fast charging current: 0.1A to 5A (I2C programmable)
• Regulated battery voltage range: 3.9V to 4.71V (I2C programmable)
• VBUS over-voltage protection threshold: 14.5V (typ)
• Over-temperature protection threshold: 160°C (typ)

Features:

• High efficiency 5A switching charger
• Synchronous 1.5MHz/0.75MHz fixed-frequency PWM controller
• Power Path Management by BATFET Control
• Support High Voltage Input (9V/12V) and Adapter (Pump Express 1.0/2.0)
• AICR Current Limit Setting via I2C and ILIM Pin
• Shipping Mode for Battery Leakage Reduction
• Automatic Charging with Pre-charge, Fast Charge (CV/CC) modes
• Protection for Input Over-Voltage, Input Bad Adapter, Battery Over-Voltage, Thermal Regulation
• ADC Conversion for VBUS, VBAT, VSYS, REGN, TS_BAT, IBUS, IBAT, TEMP_JC
• INT Output for Communication with Host Through I2C

Applications:

• Cellular Telephones
• Personal Information Appliances
• Tablet PC, Power Bank
• Portable Instruments

Package:

• WQFN-24L 4x4 (W-Type) (Exposed Pad-Option 2)

• High Efficiency 5A, 1.5MHz Switching Charger with Output Inductor DFE252012F, TOKO
• Charging Efficiency 90.25% at ICHG = 2A
• Charging Efficiency 88.86% at ICHG = 3A
• Charging Efficiency 84.2% at ICHG = 5A
• Synchronous 1.5MHz/0.75MHz Fixed-Frequency PWM Controller with Up to 95% Duty Cycle
• Power Path Management by BATFET Control
• Support High Voltage Input (9V/12V)
• Support High Voltage Input Adapter (Pump Express 1.0/2.0)
• Support IR Compensation Function from Charger Output to Cell Terminal
• Optimize Input Sourcing Capability to Prevent Overload
• AICR Current Limit Setting via I 2 C
• ILIM Pin for Current Limit Setting
• Average Input Current Limit Measurement
• Shipping Mode for Battery Leakage Reduction
• Wake Up System, Exit Shipping Mode, and Reset System by QON Pin
• Automatic Charging
• Average Input Current Regulation (AICR) :

0.1A to 3.25A in 50mA Steps

• Charge Current Regulation Accuracy : ± 7%
• Charge Voltage Regulation Accuracy : ± 1% (0 to 85 ° C)
• Protection for Overall System Considerations
• Thermal Regulation for Current Reduction and Over-Temperature Protection
• Input Over-Voltage Protection
• Input Bad Adapter Protection
• Battery Over-Voltage Protection
• Support ADC Conversion for
• VBUS, VBAT, VSYS, REGN, TS_BAT, IBUS, IBAT, TEMP_JC
• INT Output for Communication with Host Through I 2 C (Watch Dog/Polling Function)

Package Type QW : WQFN-24L 4x4 (W-Type) (Exposed Pad-Option 2)

• Cellular Telephones
• Personal Information Appliances
• Tablet PC, Power Bank
• Portable Instruments

The junction temperature should never exceed the absolute maximum junction temperature TJ(MAX), listed under Absolute Maximum Ratings, to avoid permanent damage to the device. The maximum allowable power dissipation depends on the thermal resistance of the IC package, the PCB layout, the rate of surrounding airflow, and the difference between the junction and ambient temperatures. The maximum power dissipation can be calculated using the following formula :

where TJ(MAX) is the maximum junction temperature, TA is the ambient temperature, and θ JA is the junction-to-ambient thermal resistance.

For continuous operation, the maximum operating junction temperature indicated under Recommended Operating Conditions is 125 ° C. The junction-to-ambient thermal resistance, θ JA, is highly package dependent. For a WQFN-24L 4x4 package, the thermal resistance, θ JA, is 22 ° C/W on a standard JEDEC 51-7 high effective-thermalconductivity four-layer test board. The maximum power dissipation at TA = 25 ° C can be calculated as below :

PD(MAX) = (125 ° C -25 ° C) / (22 ° C/W) = 4.54W for a WQFN-24L 4x4 package.

The maximum power dissipation depends on the operating ambient temperature for the fixed TJ(MAX) and the thermal resistance, θ JA. The derating curves in Figure 1 allows the designer to see the effect of rising ambient temperature on the maximum power dissipation.

Figure 1. Derating Curve of Maximum Power Dissipation