New Industry Products

Highly-Integrated PMIC with Safe Charging and Low-Noise LDO for Hearables and IoT

October 01, 2018 by Paul Shepard

The MAX77734 from Maxim Integrated Products is a tiny PMIC for applications where size and simplicity are critical. The IC integrates a linear-mode Li+ battery charger, low-dropout linear regulator (LDO), analog multiplexer, and dual-channel current sink driver.

The charger is designed for small-battery systems that require accurate termination as low as 0.375mA. The circuit can instantly regulate the system voltage when an input source is connected even if the battery is depleted.

Target applications include: action cameras, wearable/body cameras; fitness bands and other Bluetooth wearables' hearables including headsets, headphones and earbuds; and low-power IoT devices.

The 150mA LDO's output is programmable between 0.8V and 3.975V with I²C. The analog MUX enables an external ADC to perform conversions on battery V&I signals for power monitoring. The current sinks are capable of sinking 12.8mA each and can be programmed for LEDs to blink in custom patterns.

The MAX77734 is available in a 20-bump, 0.4mm pitch wafer-level package (WLP).

Key Features:

  • Extends Battery Life
    • 200nA Factory-Ship Mode for Long Shelf Life
    • 500nA Shutdown Current
    • 5µA Quiescent Current with LDO Enabled
    • Charger Allows Battery to Relax after Charging
  • Linear Charger Optimized for Small Battery Size
    • 5mA to 300mA Fast-Charge Current
    • Battery Regulation Voltage from 3.6V to 4.6V
    • Accurate Termination Current as low as 0.375mA
    • Instant-On Functionality provided by Maxim's Smart Power Selector™
    • JEITA Battery Temperature Monitors for Safe Charging
  • Highly Integrated
    • 150mA LDO with Power-OK Output
    • Dual-Channel Current Sink for LEDs
    • Analog Multiplexer for Power Monitoring
    • Watchdog Timer
    • On-Key Input for LDO Enable and Manual Reset
  • Small Size
    • 23mm x 1.97mm (0.5mm max height) WLP
    • 20-Bump, 0.4mm Pitch, 4 x 5 Array
    • 25mm2 Total Solution Size