LG A230 Service Manual

Internal Use Only

Service Manual

LG-A230

Date: May, 2011 / Issue 1.0

Table Of Contents

1. INTRODUCTION ...................................................................3

1.1 Purpose .....................................................................................................3

1.2 Regulatory Information ......................................................................3

1.3 Abbreviations..........................................................................................5

2. PERFORMANCE ....................................................................7

2.1 H/W Features ...........................................................................................7

2.2 Technical Speciﬁcation ........................................................................9

3. TECHNICAL BRIEF ..............................................................13

3.1 Digital Main Processor ...................................................................... 13

3.2 Power Management ......................................................................... 18

3.3 FEM with integrated Power Ampliﬁer Module

(SKY77550, U500) ...............................................................................31

3.4 Crystal(26 MHz, X100) ......................................................................33

3.5 RF Subsystem (U101) ........................................................................ 35

3.6 MEMORY(H8BCS0QG0MMR, U100) ............................................40

3.7 BT module ............................................................................................. 42

3.8 SIM Card Interface .............................................................................. 44

3.9 LCD Interface ........................................................................................ 45

3.10 Battery Charger Interface ............................................................. 48

3.11 Audio Interface ................................................................................. 49

3.12 Camera Interface(1.3M Fixed Focus Camera) ....................... 55

4. TROUBLE SHOOTING ........................................................57

4.1 RF Component .................................................................................... 57

4.2 RX Trouble .............................................................................................58

4.3 TX Trouble .............................................................................................. 64

4.4 Power On Trouble ............................................................................... 70

4.5 Charging Trouble ................................................................................ 73

4.6 Vibrator Trouble ..................................................................................76

4.7 LCD Trouble ..........................................................................................79

4.8 Camera Trouble ................................................................................... 83

4.9 Speaker / Receiver Trouble .............................................................87

4.10 Earphone Trouble ............................................................................ 90

4.11 Microphone Trouble ....................................................................... 93

4.12 SIM Card Interface Trouble ........................................................... 96

4.13 Micro SD (uSD) Trouble ................................................................. 99

4.14 Bluetooth Trouble ..........................................................................102

4.15 FM Radio Trouble ...........................................................................105

4.16 Wireless FM Radio Trouble .........................................................107

5. DOWNLOAD .....................................................................110

6. BLOCK DIAGRAM .............................................................123

7. CIRCUIT DIAGRAM ..........................................................124

8. BGA PIN MAP ..................................................................129

9. PCB LAYOUT .....................................................................131

10.ENGINEERING MODE .....................................................133

11. STAND ALONE TEST ......................................................134

11.1 Introduction .....................................................................................134

11.2 Setting Method ..............................................................................134

11.3 Tx Test .................................................................................................137

11.4 Rx Test .................................................................................................139

12. AUTO CALIBRATION ......................................................141

12.1 Overview ...........................................................................................141

12.2 Directory structure of Tachyon .................................................141

12.3 Description of Folder & File. .......................................................142

12.4 Procedure ..........................................................................................143

12.5 Tachyon Main UI .............................................................................144

12.6 AGC ......................................................................................................145

12.7 APC ......................................................................................................145

12.8 ADC ......................................................................................................145

12.9 Target Power ....................................................................................145

13. EXPLODED VIEW & REPLACEMENT PART LIST ..........146

13.1 EXPLODED VIEW .............................................................................146

13.2 Replacement Parts ........................................................................147

13.3 Accessory ..........................................................................................163

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Only for training and service purposes

1. INTRODUCTION

1.1 Purpose

This manual provides the information necessary to repair, calibration, description and download the features

of this model.

1.2 Regulatory Information

A. Security

Toll fraud, the unauthorized use of telecommunications system by an unauthorized part (for example,

persons other than your company’s employees, agents, subcontractors, or person working on your

company’s behalf) can result in substantial additional charges for your telecommunications services. System

users are responsible for the security of own system. There are may be risks of toll fraud associated with your

telecommunications system. System users are responsible for programming and configuring the equipment

to prevent unauthorized use. The manufacturer does not warrant that this product is immune from the

above case but will prevent unauthorized use of common-carrier telecommunication service of facilities

accessed through or connected to it.

The manufacturer will not be responsible for any charges that result from such unauthorized use.

B. Incidence of Harm

If a telephone company determines that the equipment provided to customer is faulty and possibly causing

harm or interruption in service to the telephone network, it should disconnect telephone service until repair

can be done. A telephone company may temporarily disconnect service as long as repair is not done.

C. Changes in Service

A local telephone company may make changes in its communications facilities or procedure. If these

changes could reasonably be expected to affect the use of the this phone or compatibility with the network,

the telephone company is required to give advanced written notice to the user, allowing the user to take

appropriate steps to maintain telephone service.

D. Maintenance Limitations

Maintenance limitations on this model must be performed only by the manufacturer or its authorized agent.

The user may not make any changes and/or repairs expect as specifically noted in this manual. Therefore,

note that unauthorized alternations or repair may affect the regulatory status of the system and may void

any remaining warranty.

1. INTRODUCTION

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Only for training and service purposes

1. INTRODUCTION

E. Notice of Radiated Emissions

This model complies with rules regarding radiation and radio frequency emission as defined by local

regulatory agencies. In accordance with these agencies, you may be required to provide information such as

the following to the end user.

F. Pictures

The pictures in this manual are for illustrative purposes only; your actual hardware may look slightly different.

G. Interference and Attenuation

Phone may interfere with sensitive laboratory equipment, medical equipment, etc.Interference from

unsuppressed engines or electric motors may cause problems.

H. Electrostatic Sensitive Devices

ATTENTION

Boards, which contain Electrostatic Sensitive Device (ESD), are indicated

by the sign. Following information is ESD handling:

• Service personnel should ground themselves by using a wrist strap when exchange system boards.

• When repairs are made to a system board, they should spread the floor with anti-static mat which is also

grounded.

• Use a suitable, grounded soldering iron.

• Keep sensitive parts in these protective packages until these are used.

• When returning system boards or parts like EEPROM to the factory, use the protective package as described.

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Only for training and service purposes

1.3 Abbreviations

For the purposes of this manual, following abbreviations apply:

Offset Phase Locked LoopOPLL

Light Emitting DiodeLED

Low Drop OutputLDO

Liquid Crystal DisplayLCD

Intermediate FrequencyIF

International Portable User IdentityIPUI

Global System for Mobile CommunicationsGSM

General Purpose Interface BusGPIB

Gaussian Minimum Shift KeyingGMSK

Flexible Printed Circuit BoardFPCB

Electrostatic DischargeESD

Electrical Erasable Programmable Read-Only MemoryEEPROM

Digital Signal ProcessingDSP

dB relative to 1 milli wattdBm

Digital Communication SystemDCS

Digital to Analog ConverterDAC

Constant Current – Constant VoltageCC-CV

Bit Error RatioBER

BasebandBB

Automatic Power ControlAPC

1. INTRODUCTION

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Only for training and service purposes

1. INTRODUCTION

Wireless Application Protocol

WAP

Voltage Control Temperature Compensated Crystal OscillatorVCTCXO

Voltage Controlled OscillatorVCO

Universal Asynchronous Receiver/TransmitterUART

Time Division Multiple AccessTDMA

Time Division DuplexTDD

Travel AdapterTA

Side Tone Masking RatingSTMR

Pseudo SRAMPSRAM

Static Random Access MemorySRAM

Sending Loudness RatingSLR

Subscriber Identity ModuleSIM

Surface Acoustic WaveSAW

Real Time ClockRTC

Root Mean SquareRMS

Receiving Loudness RatingRLR

Radio FrequencyRF

Public Switched Telephone NetworkPSTN

Phase Locked LoopPLL

Programmable Gain AmplifierPGA

Printed Circuit BoardPCB

Power Amplifier ModulePAM

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Only for training and service purposes

2. PERFORMANCE

2.1 H/W Features

Item Feature Comment

Standard Battery Lithium-Ion, 3.7V 950mAh

Stand by TIME Up to 605 hrs : Paging Period 5, RSSI 85dBm

Talk time Up to 200min : GSM Tx Level 7

Stand by time Up to 389 hours (Paging Period: 5, RSSI: -85 dBm)

Charging time Approx. 3 hours

RX Sensitivity GSM, EGSM: -109dBm, DCS: -109dBm

TX output power

GSM, EGSM: 32.3dBm(Level 5), DCS , PCS: 29.5dBm(Level 0)

SIM card type 3V / 1.8V

Display MAIN : 1.77” QVGA 160 Ý 128 pixel

Status Indicator Send Key, End Key, Navi Key (Up,Down,Left,Right)

ANT Internal

EAR Phone Jack Yes

PC Synchronization Yes

Speech coding

EFR/FR/HR

Data and Fax Yes

GPRS compatibility Class 10

Vibrator Yes

Loud Speaker Yes

Voice Recoding Yes

Microphone Yes

Travel Adapter Yes

Speaker/Receiver

MIDI SW MIDI (Mono SPK)

Camera 1.3M FF

Bluetooth / FM Radio Bluetooth version 2.1 / 76~108MHz supported

18x12Ȱ Speaker/ Receiver

2. PERFORMANCE

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Only for training and service purposes

2.2 Technical Specification

Item Description Specification

1 Frequency Band

GSM850 EGSM

TX: 824 ~ 849 MHz TX: 880 ~ 915MHz RX: 869 ~ 894 MHz RX: 925 ~ 960 MHz

DCS

TX: 1710 ~ 1785 MHz RX: 1805 ~ 1880 MHz

PCS

TX: 1850 ~ 1910 MHz RX: 1930 ~ 1990 MHz

2 Phase Error

RMS < 5 degrees Peak < 20 degrees

3 Frequency Error < 0.1 ppm

4 Power Level

Level Power Toler. Level Power Toler.

6 31dBm ·3dB 14 15dBm · 3dB

7 29dBm ·3dB 15 13dBm · 3dB

8 27dBm ·3dB 16 11dBm · 5dB

9 25dBm ·3dB 17 9dBm · 5dB

10 23dBm ·3dB 18 7dBm · 5dB

11 21dBm ·3dB 19 5dBm · 5dB

12 19dBm ·3dB

GSM850/EGSM

5 33dBm ·2dB 13 17dBm · 3dB

Level Power Toler. Level Power Toler.

1 28dBm ·3dB 9 12dBm · 4dB

2 26dBm ·3dB 10 10dBm · 4dB

3 24dBm ·3dB 11 8dBm · 4dB

4 22dBm ·3dB 12 6dBm · 4dB

5 20dBm ·3dB 13 4dBm · 4dB

6 18dBm ·3dB 14 2dBm · 5dB

7 16dBm ·3dB 15 0dBm · 5dB

DCS/PCS

0 30dBm ·2dB 8 14dBm · 3dB

2. PERFORMANCE

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Only for training and service purposes

Output RF Spectrum (due to modulation)

Offset from Carrier (kHz). Max. dBc

100 +0.5

200 -30

250 -33

400 -60

600~ <1,200 -60

1,200~ <1,800 -60

1,800~ <3,000 -63

3,000~ <6,000 -65

6,000 -71

GSM850/ EGSM

Offset from Carrier (kHz). Max. dBc

100 +0.5

200 -30

250 -33

400 -60

600~ <1,200 -60

1,200~ <1,800 -60

1,800~ <3,000 -65

3,000~ <6,000 -65

6,000 -73

DCS/PCS

Output RF Spectrum (due to switching

transient)

GSM850/ EGSM

Offset from Carrier (kHz). Max. dBm

400 -19

600 -21

1,200 -21

1,800 -24

Item Description Specification

2. PERFORMANCE

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Only for training and service purposes

Item Description Specification

Output RF Spectrum (due to switching

transient)

Offset from Carrier (kHz). Max. dBm

400 -22

600 -24

1,200 -24

1,800 -27

7 Spurious Emissions Conduction, Emission Status

8 Bit Error Ratio

GSM850, EGSM

BER (Class II) < 2.439% @-102 dBm

DCS,PCS

BER (Class II) < 2.439% @-100 dBm

9 RX Level Report Accuracy ·3 dB

10 SLR 12·3 dB

11 Sending Response

300 -12

1,000 -6

2,000 -6

3,000 -6

Frequency (Hz) Max.(dB) Min.(dB)

100 -

200 -

4,000 -

3,400 -9

-12

12 RLR 4·3 dB

DCS/PCS

2. PERFORMANCE

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Only for training and service purposes

Item Description Specification

13 Receiving Response

300 -7

500 -5

1,000 -5

3,000 -5

Frequency (Hz) Max.(dB) Min.(dB)

100 -

200 -

4,000

3,400 -10

-12

14 STMR > 17 dB

* Mean that Adopt a straight line in between 300 Hz

and 1,000 Hz to be Max. level in the range.

15 Stability Margin > 6 dB

-20

-10

dB to ARL (dB) Level Ratio (dB)

-35

-30

30.7

33.3

33.7

31.7

17.5

22.5

25.5

16 Distortion

17 Side Tone Distortion Three stage distortion < 10%

System frequency (13 MHz) tolerance

˺ 2.5 ppm

19 32.768KHz tolerance ˺ 30 ppm

20 Ringer Volume

At least 55 dBspl under below conditions:

1. Ringer set as ringer.

2. Test distance set as 1 m

2. PERFORMANCE

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Only for training and service purposes

Item Description Specification

21 Charge Current

Fast Charge : Typ. 400 mA

Slow Charge : Typ. 95mA

Total Charging Time : < 3 hours

2 -> 1

0 -> OFF

Bar Number Power

4 -> 2

-104 · 2

Under -106

-101 · 2

22 Antenna Display

Battery Indicator

(SPG:Software Power Gauge)

Low Voltage Warning

( Blinking Bar)

5% in 950mA, 1 time (standby)

10% in 950mA, 1 time (standby) 5% in 950mA, 1 time (Call)

10% in 950mA, 1 time (Call)

Forced shut down

Voltage

3.35 · 0.05V

27 Battery Type

Lithium-Ion Battery Standard Voltage = 3.7 V Battery full charge voltage = 4.2 V Capacity: 950mAh

28 Travel Charger

Switching-mode charger Input: 100 ~ 240V, 50/60 Hz Output: 4.8V, 400mA

Sustain RTC

without battery

Over 15 Mins

5 -> 4

Over -93

-93 · 2

1 -> 0 -106 · 2

50%Half Battery

100%Full Battery

PercentageBattery Bar display

2. PERFORMANCE

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Only for training and service purposes

3. TECHNICAL BRIEF

TECHNICAL BRIEF

3.1 Digital Main Processor

3. TECHNICAL BRIEF

Figure. 3.1.1 X-Gold 215 Hardware Block Diagram

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Only for training and service purposes

3.1.1 General

• Technology:

– SoC, Monolithic, 65 nm CMOS

• Package:

– eWLB, 8x8x0.8 mm

– 0.5 mm pitch

– 217 balls / 8-layer PCB

3.1.2 RF Transceiver

• Dual-band direct conversion receiver

• Tri/Quad-band possible with external circuitry

• Fully integrated digital controlled X0

• Additional buffer for 2 external system clocks

• Fully digital RF-Synthesizer incl. ȭȟ-Transmitter

3.1.3 Baseband

• DSP:

– 156 MHz TeakLite™

• MCU:

– ARM1176® @ 208 MHz

• MCU RAM:

– 3.00Mbit

• Memory I/F:

– 512 Mbit

• Modem:

– GPRS class 12, (RX/TX CS1-CS4)

– EGPRS class 12, (RX MCS1-MCS9, TX MCS1-MCS4)

• Cipher Units:

– A51/2/3

– GEA-1/2/3

• Security:

– OMTP TR0

– Secure Boot

– RSA(ROM)/SHA-1(HW accel.)

– OCDS disabling

– Certificate Management

3. TECHNICAL BRIEF

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Only for training and service purposes

• Speech Codec:

– FR / HR / EFR / NB-AMR

• Audio Codec (running on ARM1176):

– SP-MIDI

– SB-ADPCM

– MP3

– WB-AMR

– AAC/AAC+/eAAC+

• Others:

– DARP (SAIC)

– TTY

• Customization:

– E-Fuses

3.1.4 External Memory

• External Bus Unit

– 25-bit address bus (512 Mbit)

– 16-bit data bus

– 1.8V & 2.8V support

• Flash / RAM

– NAND Type

– Serial Flash SPI and SPI-4

– Parallel Flash (Page & Burst Mode)

- 16-bit Demultiplexed

- 16-bit AD-multiplexed

- 16-bit AAD-multiplexed

– iNAND Type e.g. oneNAND

• Memory card

– SD/MMC card interface with 1 or 4 data lines

3.1.5 Connectivity

• 3xUSIF (configurable either as SPI or UART), I2C, I2S; Interfaces @ 1.8V

• Direct (U)SIM 1.8/3V

• USB2.0 up to 480 Mbit/s (High Speed) w/ external USB Phy over ULPI interface

• Stereo Headset (Amplifier integrated)

• 3 external analog measurement PIN’s

• Bluetooth

3. TECHNICAL BRIEF

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Only for training and service purposes

3.1.6 Mixed Signal

• Improved audio performance

• Loudspeaker Audio Class D Amplifier, 700 mW@8 ȳ mono for hands-free and ringing

• Stereo Headset 2x30 mW@16 ȳ w/o coupling C

• Mono Earpiece 100 mW@16 ȳ

• Digital microphone supported

• Differential microphone inputs

3.1.7 FM Radio

• Integrated FM radio

– FM Stereo RDS Receiver – Sensitivity 2 ɆV EMF

– Support for US & EU bands

– Stereo recording

3.1.8 Power Management

• Direct-to-Battery Connection

– LDOs (incl. capless)

– DC/DC step-down converter

– DC/DC step-up for white LED supply

• Battery Type

– Li-Polymer

• Charging control

– Battery temperature

– Watchdog protection

– Start-up on flat battery

• External Charger

– Switch mode

• USB battery charging

– USB charging spec 1.0 compliant

• Backlight

– Up to 4 serial white LEDs (integrated LDO)

3. TECHNICAL BRIEF

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Only for training and service purposes

3. TECHNICAL BRIEF

3.1.9 Main LCD Display

• Type

– 128x160, 65k color (serial)

– QQVGA, 262k color (parallel)

• Interface

– Parallel 8/9bit MIPI-DBI Type B

– Serial MIPI-DBI Type C

– Interf. voltage at 1.8V or 2.8V

• gRacr - Display Controller (Hardware)

– 30 fps Display update without DMA (up to 60 fps) (full or partial) – Video post processing Scaling, Rotation (90¶ steps), Mirroring

– Overlay with alpha blending

– Color conversion YUV -> RGB

– 2D vector graphics (Lines, filled rectangles, Bit block transfer (e.g. sprites, scrolling, antialiased bitmapfonts)

3.1.10 Camera

• 2 Mpx YUV parallel interface

• HW JPEG encoder (39 Mpx/sec)

• 39 MHz Pixel Rate

• 15 fps@ 2 Mpx full resolution

3.1.11 Video Capabilities

• Video Decoding MPEG-4/H.263

– QCIF@30 fps

– QVGA@15 fps

• Video Encoding MPEG-4/H.263

– QCIF@15 fps

3.1.12 Audio Capabilities

• Polyphonic ring tones

– 64 voices MIDI, SP-MIDI

– FM synthesizer

• AMR-WB

• True ring tones (MP3)

• MP3, eAAC+

• G.722 SB-ADPCM encoding/decoding

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Only for training and service purposes

3. TECHNICAL BRIEF

3.2 Power Management

A mobile platform requires different power supplies for different functions. These power supplies are

generated in the integrated Power Management Unit (PMU). The PMU is designed to deliver the power for a

typical standard phone. For advanced features additional off chip power supplies might be necessary.

Figure. 3-2-1 Block Figure of the PMU Modules X-GOLD™ 215

 DC/DC Step Down Converter for 1.8V (SD1)

The DC/DC converter generates a 1.8 V supply rail. This voltage rail is used to supply main parts of the system,

like the digital core of the chip (via LDO LCORE), some parts of the mixed signal macro, parts of the RF macro

and the external memory if a 1.8 V memory is used. The efficiency of the DC/DC converter is optimized for an

average load current of 100 mA. That is the load current estimated for the GSM talk mode.

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Only for training and service purposes

3. TECHNICAL BRIEF

 Linear voltage Regulators (low dropout) LDOs

The LDOs are used to generate the supply for the different supply domains not directly supplied out of the

DC/DC converter.

 LCORE

The LCORE LDO provides the VCORE supply used for most of the digital parts of the chip. ip

 LPMU

The LPMU provides VPMU used for the PMU supply, e.g. for the startup statemachine and analog parts like

ADC, sense amplifier etc.

 LUSB

The LUSB LDO generates the supply for the USB transceiver (output driver and input). If no USB interface is

required, LUSB can be used as general purpose LDO.

 LAUX

The LAUX generates VAUX. It is a general purpose LDO and can be used for different functions depending on

the phone application, e.g. for the display or camera.

 LMMC

The LMMC generates VMMC. It is a general purpose LDO and can be used e.g. for memory cards.

 LSIM

The LSIM LDO generates the VSIM supply for the SIM card and interface. It is designed to supply Standard SIM

cards according ETSI TS 102 221.

 Other LDOs

• The RF module has implemented several LDO’s for different RF power domains.

• The mixed signal module has some LDO’s for the audio driver and microphone supply

• The FM receiver has an internal LDO for sensitive RF circuits.

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Only for training and service purposes

3. TECHNICAL BRIEF

Table. 3-2-1 Power supply Domains (without RF)

- 20 -

Only for training and service purposes

3. TECHNICAL BRIEF

3.2.1 Power on and startup

 Analog startup Circuit

Because the POR circuit and the LPBG are directly connected to the battery, it is not possible to switch them

off. If the battery voltage exceed the power on reset threshold (2.5V), the power on reset is released, the LPMU

regulator and the LRTC voltage regulator are switched on. The LPMU regulator starts in its ultra-low power

mode

The LPMU regulator generates a control signal (lpmu_OK) that enables the 50KHZ PMU oscillator. The output

clock of the oscillator is checked with a fully coded counter. A counter overflow releases the reset

(vpmu_rst_n) signal for the small PMU state-machine.

 Small first digital State-Machine

The small PMU state-machine is always connected to VPMU After starting from reset the small startup state

machine enters the SYSTEM OFF state and only continuous the startup procedure if a switch on event like first

connect, on-key, wake up or charge detect occurs.

 PMU-main State-Machine

The main PMU state-machine is always connected to VPMU also. The power up sequence driven by the PMU

state-machine can be seen in Figure18. After enabling the reference (HPGB) and waiting for the settling time,

the battery voltage is measured and compared with the power on threshold. If the battery voltage is high

enough, the SD1 DC/DC converter and the LCORE LDO are started. A timer ensures that the supply voltage

will be stable before the DCXO is enabled. The DCXO settling time is ensured using a fixed timer. After an

overflow of this timer, the reset is released for the rest of the system. The PMU state machine remains in this

System-ON state until the system is switched into the OFF state. For example the system sleep mode is

completely configured by software( for example switching off the LDO’s, switching of the DCXO etc.) and

controlled by the VCXO_enable signal. The reason for the startup is stored in the ResetSourceRead register.

 Battery Measurement

The ADC and the oscillator for the ADC needs the VDD_ADC supply voltage from the LADC LDO. LADC uses

either the charger voltage VDD_CHARGE or VDDRTC as input voltage. The input voltage is selected

automatically by a bulk switch circuit. LADC, the ADC and the oscillator are enabled on request for every

battery measurement if the charger unit is not running. This is handled by an ADC control block in one of the

state-machines. If the charger unit is running the ADC is controlled by the charger state-machine

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Only for training and service purposes

3. TECHNICAL BRIEF

Figure.3.2.1 First Part of the State Machine, Running in Different Power Domains than the Second Part

- 22 -

Only for training and service purposes

3. TECHNICAL BRIEF

Figure 3.2.2 Second (Main) Part of the Startup State Machine in the VPMU Domain

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Only for training and service purposes

3. TECHNICAL BRIEF

3.2.2 Switching on due to first connect

If the battery voltage is connected the first time, that means the system enters the first time the SYSOFF state,

this is stored in a first connect flag. If the first connect flag is set, the system will start immediately and not wait

for any other system on event in the SYSOFF state.

3.2.3 Switching on due to on-Key event

The on key is connected to the ONKEY pad. The ESD protection and the input structure of this pad are

connected to VRTC. If the ONKEY pad is forced to VRTC by an external key or similar circuit, the system starts.

The ONKEY is sampled with the PMU clock. It has to be sampled four times high before a valid on event is

generated. The status of the ON key can be read in the PMU registers, so it can be used as a functional key

during phone operation also

3.2.4 Switching on due to RTC alarm

The real time clock can generate a wakeup signal called RTC alarm. This signal is sampled from the state-

machine and after successfully detecting a high, the system is switched on.

3.2.5 Switching on due to charging

When a battery with a voltage below the SSONLEV level is inserted, the state machine will not start the system.

As long as the battery voltage stays lover than SYSONLEV the system will stay off. The only possibility to start

up the system is due to an external charger.

If an external charger is connected and detected and the battery is charged above the SYSONPRE voltage level

the system will start up.

The PMU main state machine waits in the Check battery state until the battery voltage condition is fulfilled. The

charger state machine provides the necessary pre-charge indication signal. This pre-charge signal is

denounced in a small counter to have a stable signal. This is important, especially in half/full-wave charging

where the charger detection is switching between charger detected/not detected according the AC supply

frequency. reasons

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Only for training and service purposes

3. TECHNICAL BRIEF

For details on pre-charging see the charger chapter. The charger is controlled by an independent state

machine. The pre-charge signal is used to trigger the pre-charge signal is used to trigger the pre-charge

functionality. The charger state machine fully control the pre-charge, the PMU-state machine now changes to

state HPBG on state and the system starts. This state change is indicated to the charger state-machine to

enable the charger watchdog for safety

3.2.6 Power Supply Start-up sequence

In order to avoid an excessive drop on the battery voltage caused by in-rush current during system power-on,

possibly leading to system instability and “hick-ups” a staggered turn-on approach for the regulators is

implemented. The regulators are turned on in a well defined sequence, thus spreading the in-rush current

transients over time.

The IO’s of X-GOLD TM 215 are isolated in OFF mode (core supply is off). The isolation signal is controlled by

the PMU state machine. This ensures that the PADs are in a well defined state during core supply settling. This

allows to power up the LCORE core regulator and wait for the core to reach reset state before powering up the

I/O supply regulators.

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Only for training and service purposes

3. TECHNICAL BRIEF

Figure 3.2.3 Start Up Sequence (triggered by First Connect Event)

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Only for training and service purposes

3. TECHNICAL BRIEF

3.2.7 External Reset Handling

The chip reset can be controlled by an external RESET_N ball. If this ball is pulled low, the chip will be reset. All

PMU registers are reset during the external reset including LSIM control bits. The PMU statemachines are also

not reset from the external reset.

An SW or watchdog reset will not reset the PMU registers. A SW and Watchdog reset is seen on the reset_n pad

to allow the reset of external devices. Basically there are three reset sources, first the reset signal controlled by

the PMU (reset_pmu_n_o), second the reset signal controlled by the SCU (resetout_o) and third the external

reset (RESET_N). The SCU reset is triggered by SW (for example due to a SW reset or watchdog reset). The PMU

reset is controlled by the PMU state machine. The output of the reset handling block is the reset_postscu_n_o signal. This signal controls for example the ɆC

subsystem and releases reset for the controller. During normal start up, the PMU releases the reset_pmu_n_o

signal after entering the SYSTEM ON state. At this time the resetout_o signal is high, the RESET_N pad is not

pulled low and therefore the reset_postscu_n_o signal follows the reset_pmu_n_o signal. That means the ɆC reset will be released and the ɆC starts operation. If the SW triggers an external reset via the

SCU, signal resetout_o will be forced to low for a certain time and RESET_N will be forced to low by the open

drain driver. At the same time the feedback to the SCU will be masked to not reset the baseband. The RESET_N

pad is in the VDDRTC domain but the internal pull up is connected to the VDD_VDIG1 (1.8V) domain. That

allows the pad to be used as reset for external devices running in the VDD1V8 domain. The RESET_N pad can

also be used to monitor the chip internal reset condition during startup.

The open drain driver is a weak driver, that means it can be forced to high during debug from external pushing

some current into the pad. In testmode signal reset_pmu_n_o is high, that means the chip reset is fully

controlled from external

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Only for training and service purposes

3. TECHNICAL BRIEF

3.2.8 Sysclock Switching

The PMU controls the rf_sysclk_en signal of the DCXO in the RF macro. During startup the PMU enables the

DCXO. After the system is running the DCXO is controlled by the SCU of the baseband by using the

vcxo_enable signal. This is handled by a dedicated logic in the PMU, see Figure 21. As long as

rf_sysclk_en_pmu, the output of the PMU state-machine is high, vcxo_enable controls the rf_sysclk_en signal

to the RF. If rf_sysclk_en_pmu is low, the DXCO is switched off, independent from vcxo_enable.

Figure 3.2.4 PMU, CGU and External Reset

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Only for training and service purposes

3. TECHNICAL BRIEF

3.2.10 Software Reset

A software reset does not affect any PMU register. The PMU register are reset with the reset_pmufsm_n_o

signal. That means all PMU register are reset in OFF state. For details about the SW reset see chapter External

Reset Handling

3.2.9 Undervoltage Shutdown

In active mode the PMU periodically measures the battery voltage using the ADC from the charger unit. If the

battery is measured to be below the programmable shut-down level (called SYSOFF), the system changes to

OFF mode. This is done via the SHUTDOWN state of the PMU state machine. (see chapter switch OFF)

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Only for training and service purposes

3. TECHNICAL BRIEF

3.2.11 PMU Clock

During the first startup (for example plugging in a battery) a PMU internal oscillator is used for generation of

the PMU clock (pmu_clock). The frequency is slightly above 32 kHz (typ. 50 kHz) to be out of the audio band

also for worst case devices. After first startup the software shall enable the 32 kHz crystal oscillator. It is not

possible to use the 32 kHz oscillator during first startup, because the settling time of the oscillator can be

quite long. After the 32 kHz oscillator is running and settled the software shall switch the PMU clock to the 32

kHz clock and disable the internal PMU oscillator for power saving reasons. The 32 kHz oscillator shall never

be disabled after the PMU clock has been switched. The ADC in the charger unit has it’s own oscillator

generating a frequency of about 10 MHz. This oscillator is running during charging and during battery

measurements triggered by the PMU. It is off otherwise.

3.2.12 System Sleep Mode

The sleep mode is controlled by using the VCXO_enable signal. This signal is used to switch the LDO’s and the

DC/DC converter SD1 in a programmable way into its low power mode (PFM). In addition DC/DC converter

SD1 can be configured to change the output voltage to a lower value for additional power saving.

VCXO_enable is also used to deactivate the HPBG and setting LDO LPMU in the ultra-low-power mode. In

addition the DCXO is switched off by the VCXO_enable signal. The VCXO_enable signal is also used to switch

some LDO’s (software configured) to sleep and/or off mode or to change the output voltages of said LDO’s.

The state of the main PMU state machine is not changed due to VCXO_enable.

3.2.13 DC/DC Pre-Load Register Handling

The DC/DC converter works in different modes. If the mode is switched from PFM to PWM the pulse-width of

the DC/DC converter depends on the current battery voltage (and on the output voltage). The PMU state-

machine knows the battery voltage because of the battery supervision function. Depending on this value it

selects a startup pulse-width for the DC/DC converter out of a register table. (4-values)

3.2.14 Power Down Sequence

Setting bit OFF in the GeneralControl register switches the system into OFF mode. After the turn off event, the

state-machine switches to the SHUTDOWN state. The reset_pmu_n_o signal changes to low, the I/O pads are

isolated using the padisolation_n signal, the LCORE LDO and the SD1 DC/DC converter are switched off, the

LPMU LDO is switched to ultra-low power mode, the DCXO is turned off and the bandgap buffer is disabled.

Before switching OFF the software shall have enabled the 32 kHz oscillator and has switched the PMU clock to

the 32 kHz clock to archive the target OFF current

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Only for training and service purposes

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