USB Type-C, 3A Switch-Mode Buck Charger with Integrated CC Detection

Maxim Integrated introduced the MAX77860, a high-performance single input switch mode buck charger that features USB Type-C CC detection capability. The charger also has reverse boost capability and a Safeout LDO. The charger features a single input, which works for both USB and high-voltage adapters. It supports USB Type-C CC detection under BC 1.2 specification, and the power-path switch is integrated into the chip. (See simplified block diagram above).

This switched-mode battery charger with two integrated switches provides small inductor and capacitor sizes has programmable battery charging current and is suited for portable devices such as smartphones, IoT devices, and other Li-ion battery powered electronics. Other applications for the chargers include charging for 1S Li-ion applications, mobile point-of-sale devices, portable medical equipment, and portable industrial equipment

All MAX77860 blocks connected to the adapter/USB pin are protected from input over-voltage events up to 14V. The USB-OTG output provides true-load disconnect and is protected by an adjustable output current limit.

It has an input current limit up to 4.0A and can charge a single-cell battery up to 3.15A. When configured in reverse-boost mode, the IC requires no additional inductors to power USB-OTG accessories.

Maxim designed the switching charger with a special CC, CV, and die temperature regulation algorithm, as well as I2C programmable settings to accommodate a wide range of battery sizes and system loads. The on-chip ADC can help monitor the charging input voltage/current, battery voltage, charging/discharging current, and the battery temperature.

The MAX77860 communicates through an I2C 3.0 compatible serial interface consisting of a bidirectional serial data line (SDA) and a serial clock line (SCL). The IC comes in a 3.9mm x 4.0mm, 81-bump (9 x 9 array), 0.4mm pitch, wafer-level package (WLP).

Key Features

• Single-Input Switch Mode Charger
• Up to 14V Protection
• 4.0V to 13.5V Input Operating Range
• Switching Charger with D+/D- Charger Detection
• Up to 4.0A Input Current Limit with Adaptive Input Current Limit (AICL)
• Up to 3.15A Battery Charging Current Limit
• Optional External Sense Resistor
• CC, CV, and Die Temperature Control
• Supports USB-OTG Reverse Boost, up to 1.5A Current Limit
• Master-Slave Charging Capability, up to 6A Charge Current
• Integrated Battery True-Disconnect FET
• Rated up to 9ARMS, Discharge Current Limit (Programmable)
• USB Type-C Detection
• Integrated VCONN Switch
• CC Pin
• D+/D- Detection for USB HVDCP
• BC 1.2 Support
• One Safe-out LDO
• I2C-Compatible Interface