SDI Technologies SDIO Card manual Power Control Support for the Sdio Host, Power Selection

©Copyright 2000-2007 SD Card Association

SDIO Simplified Specification Version 2.00

11.2.2Power Selection

Power Selection defines two power modes for a function: Lower Current Mode and Higher Current Mode. A card implementing Power Selection gives the host the choice between these two power modes. These modes can be used for functions, such as a radio, which can operate in full performance (Higher Current Mode) or reduced performance (Lower Current Mode). A card’s support of Power Selection is indicated with the SPS bit (Support Power Selection) in the FBR. The host enables Power Selection with the EPS bit (Enable Power Selection) in the FBR.

11.2.3High-Power Tuples

Six new tuples are defined in version 1.10 for each function tuple.

•Average power required when Master Power Control is not enabled (TPLFE_SP_AVG_PWR_3.3V)

•Peak power required when Master Power Control is not enabled (TPLFE_SP_MAX_PWR_3.3V)

•Average power required in Higher Current Mode (TPLFE_HP_AVG_PWR_3.3V)

•Peak power required in Higher Current Mode (TPLFE_HP_MAX_PWR_3.3V)

•Average power required in Lower Current Mode (TPLFE_LP_AVG_PWR_3.3V)

•Peak power required in Lower Current Mode (TPLFE_LP_MAX_PWR_3.3V)

These values are 16 bits long with a 1mA/step resolution. This allows a value of 0 to 65,535 mA to be used. Current varies depending on the voltage. These tuples are defined in 3.1-3.5V or 2.7-3.6V range. When a new voltage range is added in future specification, another six tuples will be added.

Table 11-1 shows which tuples a host shall refer to depending on the host version and the settings of EMPC and EPS bits.

Host	EMPC	EPS	Reference TPLs	Comments
Ver 1.0	Don’t care	Don’t care	TPLFE_OP_MIN_PWR
			TPLFE_OP_AVG_PWR
			TPFLE_OP_MAX_PWR
Ver 1.1	0	Don’t care	TPLFE_SP_AVG_PWR_3.3V	Same as TPLFE_OP_AVG_PWR
			TPLFE_SP_MAX_PWR_3.3V	Same as TPFLE_OP_MAX_PWR
Ver 1.1	1	0	TPLFE_HP_AVG_PWR_3.3V	Non zero value is required when
			TPLFE_HP_MAX_PWR_3.3V	SMPC=1
Ver 1.1	1	1	TPLFE_LP_AVG_PWR_3.3V	Non zero value is required when
			TPLFE_LP_MAX_PWR_3.3V	SPS=1

Table 11-1 Reference Tuples by Master Power Control and Power Select

A version 1.10 SDIO card shall implement the six new tuples. A card which has SMPC set to 1, shall set a non-zero value to TPLFE_HP_AVG_PWR_3.3V and TPLFE_HP_MAX_PWR_3.3V. A card which has SPS set to 1, shall set a non-zero value to TPLFE_LP_AVG_PWR_3.3V and TPLFE_LP_MAX_PWR_3.3V. TPLFE_SP_AVG_PWR_3.3V and TPLFE_SP_MAX_PWR_3.3V should be set to the same value as TPFLE_OP_AVG_PWR and TPLFE_OP_MAX_PWR respectively.

11.3Power Control Support for the SDIO Host

11.3.1Version 1.10 Host

The following are requirements for a version 1.10 host:

•The host shall recognize new Power Control registers and tuples as defined in SDIO Specification Version 1.10.

•Power Control bits (SMPC, EMPC) in the CCCR

•Power Selection bits (SPS, EPS) in the FBR

•High-Power Tuples

•The host shall know its own power supply ability

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