Buck Converter Extends Battery Life of USB Type-C Gear

Maxim Integrated Products has announced the MAX77756, a 24 V, 500 mA, low quiescent current (IQ) buck converter. The product targets developers of multi-cell, USB Type-C products in need high current, dual inputs and I2C support. USB Type-C products must generate an always-on 3.3 V rail to detect USB insertions. Products utilizing the Power Delivery (PD) voltage range (5 V to 20 V) can generate an always-on (1.8 V /3.3 V /5.0 V) digital supply MAX77756_EVKit_imagerail for the port controller using the MAX77756 step-down converter. In addition, the MAX77756 has a 2 0 μA quiescent current that extends battery life by reducing idle power consumption. To simplify the system design, the MAX77756 has a dual input ideal diode ORing circuit that allows the chip to power from the external USB source if the battery is empty.

Multi-cell battery-operated devices—such as ultrabooks, laptops, tablets, drones and home automation appliances—can easily evolve to Type-C with PD using the flexible MAX77756 power supply. The MAX77756 has a unique combination of wide input voltage range, low quiescent current, higher current load, dual input, and I2C for flexibility and programmability. There is also a default power mode if customers do not want to use the I2C bus. The MAX77756 is a robust IC with short-circuit and thermal protection, 8ms internal soft-start to minimize inrush current, proven current-mode control architecture, and up to 26V input voltage standoff.

Key Advantages

  • Low quiescent current: 1.5 μA Buck and 20 μA MUX for always-on operation
  • High efficiency: Up to 92% with integrated power MUX
  • Small solution size: 2.33mm x 1.42mm 15-bump WLP; no external Schottky array needed
  • Wide input voltage: Operates on full VBUS range (5 V – 20 V) and VBATT (2S, 3S, 4S Li+)

MAX77756 is available from stock and priced at $0.65 (10,000+)..An evaluation board MAX77756EVKIT# (see photo) is available from stock and priced at $70

Maxim Integrated Products | www.maximintegrated.com