iRiver battery information

H100

Current consumption

The following values were gathered by connecting the battery connector inside the player directly to an Agilent power supply. After that the voltage level was set to 3.70V and current limit to 2.000A.

Function	Current
System current (CPU idle 11 MHz)	39 mA
System current (CPU idle 48 MHz)	58 mA
System current (CPU idle 120 MHz)	81 mA
Decoding (CPU 48 MHz)	74 mA
Decoding (CPU 120 MHz)	115 mA
Optical out enabled	+10 mA
Backlight (main unit)	+23 mA
Disk buffering while playing (CPU 120 MHz)	~450 mA
Disk spinning	+110 mA

The decoding current was same no matter what codec/bitrate we used or if the playback was paused or not. Also the battery indicator in debug menu is accurate, only with +- 0.05V error. If a fully charged battery level (4.2V) was put to the system, CPU takes only 51 mA at 48 MHz. With empty battery (3.0V) the system current was 73 mA.

Graphs

The following results were gathered by running mpa2wav in a loop and collecting battery level (For the technically inclined, I did this by adding int adc_read(int) to the plugin api struct, and calling adc_read(2) from my plugin) each time the decoding starts over.

Logs attached - see bottom.

11MHz:

48MHz:

120MHz:

Same as the above, except only read the mp3 once, and never write anything (meaning less HDD access, but still access when writing the battery log).