13892 datasheet(82/158 Pages) FREESCALE

82 / 158 page

FUNCTIONAL DEVICE OPERATION

SUPPLIES

Analog Integrated Circuit Device Data



Freescale Semiconductor

MC13892

Figure 23. Boost Regulator Architecture

Enabling of SWBST is accomplished through the SWBSTEN SPI control bit.

Figure 24. Boost Regulator Efficiency

LINEAR REGULATORS

This section describes the linear regulators provided. For convenience, these regulators are named to indicate their typical or

possible applications, but the supplies are not limited to these uses and may be applied to any loads within the specified regulator

capabilities.

A low-power standby mode controlled by STANDBY is provided in which the bias current is aggressively reduced. This mode

is useful for deep sleep operation where certain supplies cannot be disabled, but active regulation can be tolerated with lesser

parametric requirements. The output drive capability and performance are limited in this mode. Refer to STANDBY Event

Definition and Control in Power Control System for more details.

Some dedicated regulators are covered in their related chapters rather than in the Supplies chapter (i.e., the VUSB and VUSB2

supplies are included in Connectivity).

Apart from the integrated linear regulators, there are also GPO output pins provided to enable and disable discrete regulators

or functional blocks, or to use as a general purpose output for any system need. For example, one application may be to enable

a battery pack thermistor bias in synchronization with timed ADC conversions.

Table 52. Switch Mode Supply SWBST Control Function Summary

Parameter

Value

Function

SWBSTEN

SWBST OFF

SWBST ON

5V Boost Efficiency

(Vin = 3.6V, Vou t = 5V)

80.00

85.00

90.00

95.00

100.00

01 00

2 00

300

Boost Load Current (mA)

13892 Datasheet(PDF) 82 Page - Freescale Semiconductor, Inc