Neo 1973 GTA01 Power Management

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m (Userspace API: add battery life.)
m (Approximate power draw of various subsystems. Estimated from datasheets.: Added comment that 3500 is probably in mWh)
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== Approximate power draw of various subsystems. Estimated from datasheets.==
 
== Approximate power draw of various subsystems. Estimated from datasheets.==
  
The battery has a total of 1200mAh, at 3.6V. This is approximately 3500mAh, once power supply losses are taken into account.
+
The battery has a total of 1200mAh, at 3.6V. This is approximately 3500mAh (--[[User:Xkr47|xkr47]] 23:12, 19 February 2007 (CET) surely this should be 3500'''mWh'''?), once power supply losses are taken into account.
  
 
* LCD  
 
* LCD  

Revision as of 23:12, 19 February 2007

Contents

Voltages

VB

  • Battery terminal voltage
  • Used by
    • LM4857 Amplifier
    • PCF50606 PMU
    • LCM Backlight
    • U7607 AVDD regulator
    • U7608 VTXCO_2V8 regulator

CORE_1V8

This is the S3C2410 Core Voltage

  • Generated by PMU DCUD

IO_3V3

  • Generated by PMU DCDE
  • Used by
    • Vibrator
    • FLASH_3V3 (see below)
    • Touch panel transistors
    • S3C2410 VDDA_ADC
    • S3C2410 VDDOP
    • S3C2410 VDDMOP
    • S3C2410 nBATT_FLT
    • U1502 (latch for GSM UART)
    • S3C2410 EXTCLK ???
    • SDRAM

GL_3V3

  • Generated by PMU DCDF
  • Used by
    • AGPS
  • Controlled by
    • PMU

PM Driver

  • Switch on/off if GPS is used or not

Initial state

  • disabled by u-boot PMU initialization

CODEC_3V3

  • Generated by PMU IOVDD
  • Used for
    • Audio Codec (digital and analog)
  • Controlled by
    • PMU Driver

PM Driver

  • mostly included in ASoC, right?
  • switch on, only if Audio path is required.

Initial state

  • disabled by PMU initialization in u-boot

LCM_3V3

  • Generated by PMU LPVDDD
  • Used by
    • Headset/GSM Uart Latch
    • LCM

PM Driver

  • check whether we really need to switch this off, since LCM has sophisticated PM features

Initial state

  • enabled by u-boot PMU initialization

BT_3V15

  • Generated by PMU D1REG

PM Driver

  • has to be powered up before Bluetooth can be used
  • Bluetooth device automatically enumerates at bus

Initial state

  • disabled by u-boot PMU initialization

GL_2V5

  • Generated by PMU D2REG
  • Used by
    • AGPS
  • Controlled by
    • PMU Driver

PM Driver

  • switch on only in case GPS is enabled

Initial state

  • disable by u-boot GPIO initialization

USER1

FIXME: no idea what this is for

  • Generated by PMU D3REG

PMU Driver

  • permanently disabled

Initial state

  • disabled by PMU initialization in u-boot

FLASH_3V3

  • Derived from IO_3V3
  • Used by
    • NAND Flash
  • Controlled by
    • SD_EN GPIO

PM Driver

  • do we really want to switch it on/off before every flash access?
  • if we go to standby, IO_3V3 will be switched off, thus FLASH_3V3 is off, too

Initial state

  • on, enabled by u-boot GPIO initialization

AVDD

  • Generated by U6707
  • Used by
    • AGPS
  • Controlled by
    • EN_AGPS3V GPIO

PM Driver

  • Switch on only if GPS enabled

VTCXO_2V8

  • Generated by U7608
  • Used by
    • AGPS
  • Controlled by
    • EN_GPS2V8 GPIO

PM Driver

  • enable only if GPS is used.

Initial State

  • disabled by u-boot GPIO initialization

SD_3V3

  • Derived from IO_3V3
  • Used by
    • microSD slot
  • Controlled by
    • SD_ON GPIO

PM Driver

  • we don't want to switch this off while mounted, do we?


Initial state

  • probably disabled, unless somebody uses 'mmcinit' from u-boot
  • but we can't disable it without disabling NAND.
  • result: enabled by u-boot GPIO initialization

Kernel API

Userspace API

Approximate power draw of various subsystems. Estimated from datasheets.

The battery has a total of 1200mAh, at 3.6V. This is approximately 3500mAh (--xkr47 23:12, 19 February 2007 (CET) surely this should be 3500mWh?), once power supply losses are taken into account.

  • LCD
    • 200mW with backlight at full brightness
    • 40mW with backlight at 10%
      • Based on similar 2.8" LCDs.
  • CPU
    • 320mW @ 200MHz
    • 450mW @ 266MHz
    • 140mW @ 200MHz idle.
    • 50mW @ 12MHz (slow mode)
      • These include fudge factors for RAM and other systems, from the CPU datasheet.
  • Bluetooth ?
  • GSM ?
  • GPS
    • 25mA
      • Based on comparison with a broadly similar (though not as fully featured chip from Maxim

USB seems unlikely to work in slow mode. The LCD controller is unknown - the product notes say that it has RAM, which may imply it can self-refresh.

This would imply that with the CPU constantly on in low power mode, GPS and GSM blipping on and off, and display off, the worst case power consumption is probably around 70mW, leading to a battery life of 2 days. If the CPU is turned off, battery life rises significantly.

With everything on, playing video with sound, for example should get well over 4 hours.

Personal tools

Voltages

VB

  • Battery terminal voltage
  • Used by
    • LM4857 Amplifier
    • PCF50606 PMU
    • LCM Backlight
    • U7607 AVDD regulator
    • U7608 VTXCO_2V8 regulator

CORE_1V8

This is the S3C2410 Core Voltage

  • Generated by PMU DCUD

IO_3V3

  • Generated by PMU DCDE
  • Used by
    • Vibrator
    • FLASH_3V3 (see below)
    • Touch panel transistors
    • S3C2410 VDDA_ADC
    • S3C2410 VDDOP
    • S3C2410 VDDMOP
    • S3C2410 nBATT_FLT
    • U1502 (latch for GSM UART)
    • S3C2410 EXTCLK ???
    • SDRAM

GL_3V3

  • Generated by PMU DCDF
  • Used by
    • AGPS
  • Controlled by
    • PMU

PM Driver

  • Switch on/off if GPS is used or not

Initial state

  • disabled by u-boot PMU initialization

CODEC_3V3

  • Generated by PMU IOVDD
  • Used for
    • Audio Codec (digital and analog)
  • Controlled by
    • PMU Driver

PM Driver

  • mostly included in ASoC, right?
  • switch on, only if Audio path is required.

Initial state

  • disabled by PMU initialization in u-boot

LCM_3V3

  • Generated by PMU LPVDDD
  • Used by
    • Headset/GSM Uart Latch
    • LCM

PM Driver

  • check whether we really need to switch this off, since LCM has sophisticated PM features

Initial state

  • enabled by u-boot PMU initialization

BT_3V15

  • Generated by PMU D1REG

PM Driver

  • has to be powered up before Bluetooth can be used
  • Bluetooth device automatically enumerates at bus

Initial state

  • disabled by u-boot PMU initialization

GL_2V5

  • Generated by PMU D2REG
  • Used by
    • AGPS
  • Controlled by
    • PMU Driver

PM Driver

  • switch on only in case GPS is enabled

Initial state

  • disable by u-boot GPIO initialization

USER1

FIXME: no idea what this is for

  • Generated by PMU D3REG

PMU Driver

  • permanently disabled

Initial state

  • disabled by PMU initialization in u-boot

FLASH_3V3

  • Derived from IO_3V3
  • Used by
    • NAND Flash
  • Controlled by
    • SD_EN GPIO

PM Driver

  • do we really want to switch it on/off before every flash access?
  • if we go to standby, IO_3V3 will be switched off, thus FLASH_3V3 is off, too

Initial state

  • on, enabled by u-boot GPIO initialization

AVDD

  • Generated by U6707
  • Used by
    • AGPS
  • Controlled by
    • EN_AGPS3V GPIO

PM Driver

  • Switch on only if GPS enabled

VTCXO_2V8

  • Generated by U7608
  • Used by
    • AGPS
  • Controlled by
    • EN_GPS2V8 GPIO

PM Driver

  • enable only if GPS is used.

Initial State

  • disabled by u-boot GPIO initialization

SD_3V3

  • Derived from IO_3V3
  • Used by
    • microSD slot
  • Controlled by
    • SD_ON GPIO

PM Driver

  • we don't want to switch this off while mounted, do we?


Initial state

  • probably disabled, unless somebody uses 'mmcinit' from u-boot
  • but we can't disable it without disabling NAND.
  • result: enabled by u-boot GPIO initialization

Kernel API

Userspace API

Approximate power draw of various subsystems. Estimated from datasheets.

The battery has a total of 1200mAh, at 3.6V. This is approximately 3500mAh (--xkr47 23:12, 19 February 2007 (CET) surely this should be 3500mWh?), once power supply losses are taken into account.

  • LCD
    • 200mW with backlight at full brightness
    • 40mW with backlight at 10%
      • Based on similar 2.8" LCDs.
  • CPU
    • 320mW @ 200MHz
    • 450mW @ 266MHz
    • 140mW @ 200MHz idle.
    • 50mW @ 12MHz (slow mode)
      • These include fudge factors for RAM and other systems, from the CPU datasheet.
  • Bluetooth ?
  • GSM ?
  • GPS
    • 25mA
      • Based on comparison with a broadly similar (though not as fully featured chip from Maxim

USB seems unlikely to work in slow mode. The LCD controller is unknown - the product notes say that it has RAM, which may imply it can self-refresh.

This would imply that with the CPU constantly on in low power mode, GPS and GSM blipping on and off, and display off, the worst case power consumption is probably around 70mW, leading to a battery life of 2 days. If the CPU is turned off, battery life rises significantly.

With everything on, playing video with sound, for example should get well over 4 hours.