ADP3500

REV.PrP 2/6/02

- 12 -

Theory of Operations

As illustrated in Figure 1 at the beginning, ADP3500 can be divided into two high level blocks – Analog and Logic.The Analog

block mainly consists of LDO regulators, battery charger, reference voltage, and voltage detector sub-blocks, all of which are

powered by the main power source(VBAT), namely the main battery or the charging adapter. On the other hand, the Logic block is

more complicated. All the Logic sub-blocks are also powered by VBAT except the RTC counter, 32MHz Output control, RESET

Output, and Stay-Alive Timer. These sub-blocks are powered from RTCV pin, as indicated in Figure 4 in shaded area.

[VBAT]

5

4

3

2

1

POWER ON

KEYPAD I/F

GPIO

SERIAL I/F

RESET

[RTCV]- RTC BLOCK

10

32K OUTPUT

CONTROL

RESET OUTPUT

9

11

RTC COUNTER

STAY-ALIVE TIMER

LDO CONTROL

INTERRUPT

CONTROL

DELAY 10mS

6

7

8

ANALOG

BLOCK

Figure 4. Power partitioning of sub-blocks

1. ANALOG BLOCKS

1.1 LOW DROP-OUT(LDO) REGULATORS

There are total four Sub-LDOs for each LDO1, 2, 3, and 6, in order to meet lower power consumption at light load (stand-by

operation). They are used at low load condition, but they are continuously ON even if the each Main-LDOs are ON. The LDO3 and

3b are used for Coin cell and LDO3b is always ON until Main battery (VBAT) is downed to 2.5V due to DDLO function. LDO7 and

9 are controlled with SLEEP- signal. For detail of LDO ON/OFF control, please refer to Section “2.8 LDO Control”.

Table 1. Ground currents of LDOs with each handset operations.

LDO names

Baseband

VDD

Baseband

Core

Coin Cell Audio

Vibrator

Baseband

AVDD

RF

Rx1

RF

Tx

RF

Rx2

RF

Option

Option

Main

REF

Total LDO

IGND

LDO #

1

6

3

4

5

2

7

8

9

10

11

Power OFF

OFF

OFF

10

µA

OFF

OFF

OFF

OFF

OFF

OFF

OFF

OFF

20

µA30µA

Light load

10

µA5µA10µA

OFF

OFF

5

µA

OFF

OFF

OFF

OFF

OFF

20

µA50µA

Mid-load

60

µA55µA60µA

OFF

OFF

55

µA

OFF

OFF

OFF

50

µA

OFF

20

µA

300

µA

Stand-

by

mode

Active load

60

µA55µA60µA

OFF

OFF

55

µA50µA50µA50µA50µA

OFF

20

µA

450

µA

Talk

60

µA55µA60µA50µA

OFF

55

µA50µA50µA50µA50µA50µA20µA

550

µA

Ring

60

µA55µA60µA50µA50µA55µA50µA50µA50µA50µA50µA20µA

600

µA

PRELIMINARY TECHNICAL DATA