描述

The AS3711 is a compact System PMU with integrated battery charger and back light driver. The device offers advanced power management functions. All necessary ICs and peripherals in a battery powered mobile device are supplied by the AS3711. It features 3 DCDC buck converters as well as 8 low noise LDOs. The different regulated supply voltages are programmable via the serial control interface. 4MHz operation with 1uH coils are reducing cost and PCB space.

AS3711 further features a DCDC buck controller which is ideal to support processor core currents up to 3A. The threetwo step-up converter generate voltages e.g. the backlight, classD amplifier, USB host support or LCD display supply. Both constant voltage (e.g. OLED supply) as well as constant current (white LED backlight) operations with three current sinks are possible. An internal voltage protection is limiting the output voltage in the case of external component failures.

AS3711 contains a linear or switching mode Li-Ion battery charger with constant current and constant voltage. The maximum charging current is 1.5A. An integrated battery switch and an optional external switch are separating the battery during charging or whenever an external power supply is present. With this switch it is also possible to operate with no or deeply discharged batteries. A programmable current limit (100mA - 2.5A) can be used to control the maximum current used from a USB supply or charger input. Additional features are a 28V OV protection and battery temperature supervision. The single supply voltage may vary from 2.7V to 5.5V.

主要特征

Voltage Generation:

• 3 DCDC step down regulators (2-4MHz)
• DCDC step down controller
• 2 analog low noise LDOs, 6 digital LDOs
• 1 ultra low power always on LDO 2.5V, 10mA
• Power supply supervision
• 4sec and 8sec emergency shut-down
• Stand-by function with voltage selection

HV Backlight Driver:

• 2x step up with external transistor
• Voltage control mode and over-voltage protection
• 3 programmable current sinks (max. 40mA)
• Possible external PWM dimming input (DLS, CABC)

Battery Charger:

• Programmable trickle charging (25-220mA)
• Programmable constant current charging (up to 1500mA)
• Programmable constant voltage charging (3.9V-4.25V)
• Charger time-out and temperature supervision
• Selectable current limitation for USB mode
• Integrated battery switch & ideal diode (linear mode)
• External battery switch control (switching mode)
• External 28V OV protection

Supervisor:

• Automatic battery monitoring with interrupt generation and selectable warning level
• Automatic temperature monitoring with interrupt generation and selectable warning and shutdown levels

Real Time Clock:

• Ultra low power 32kHz oscillator
• Sec and minute counter, auto wake-up
• Programable alarm
• Repeating alarm (seconds, minutes, 2 minutes, or 8 minutes)
• 32kHz clock output to peripheral
• <1μA total power consumption

General Purpose IOs:

• 10-bit general purpose ADC input
• Wake-up/sleep and DVM input
• PWM (DLS, CABC) dimming input
• Status output for: charger, low battery, power good and step-up overcurrent
• Q32k clock output
• Interrupt output
• PWM output
• Step-up feedback input

OTP programmable BOOT Sequence:

• Programmable regulator default voltages
• Programmable start-up sequence
   

General Purpose ADC:

• 10-bit resolution
• Several internal / external sources

 
 Control Interface:

• I²C control lines, including watchdog
• ON input
• Bidirectional reset, with selectable delay
• Ultra low power standby mode

产品应用

The device is suitable for portable media players, portable navigation devices, e-books, mobile Iternet devices, and tablet
PCs.

Block diagram for AS3711 System PMIC