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Temperature Compensation Coefficients (TCOMP) – Address 0x7F

Power Modes

bq27010, bq27210

SLUS707B – APRIL 2006 – REVISED JANUARY 2007

Discharge Rate Compensation Threshold

DCOFF[2:0]

0

0

1

(DCGN / 256) * 1C / 8

2

(DCGN / 256) * 2C / 8

3

(DCGN / 256) * 3C / 8

4

(DCGN / 256) * 4C / 8

5

(DCGN / 256) * 5C / 8

6

(DCGN / 256) * 6C / 8

7

(DCGN / 256) * 7C / 8

(1)

C = ILMD * 256

The discharge compensation capacity reduction (DCMP) is a function of discharge rate, temperature, and age

(cycle count). There is no compensation if the DCGN factor increased for age and temperature times AI is less

than the DCOFF threshold (DCMP

≥ 0). The following is the combined equation for the DCMP reduction:

DCMP = AI * (ADCGN / 256) * (1 + TCGN * (273 + TOFF – T) / 32) – DCGN * DCOFF * ILMD / 8

ADCGN = DCGN * (1 + TCGN * (CYCT / 16) * GAF / 32)

If PKCFG[1] = 1, the bqJUNIOR assumes a fixed value of 0x6C for DCOMP, giving a discharge rate

compensation gain of 5.08% with a compensation offset threshold of C/2. This frees the EEPROM location of

0x7E for use as a programmable identification byte. If DCOMP is updated using the UPCOMP host command

(see Device Control section), the value written by the host for DCOMP will be used regardless of the bit 1 value

in PKCFG.

This register is used to set the compensation coefficients for temperature. These coefficients are used to scale

the aged discharge rate compensation for improved accuracy of predicted available capacity at cold

temperatures.

BIT 7

BIT 6

BIT 5

BIT 4

BIT 3

BIT 2

BIT 1

BIT 0

NAME

TCGN[4]

TCGN[3]

TCGN[2]

TCGN[1]

TCGN[0]

TOFF[2]

TOFF[1]

TOFF[0]

TCGN[4:0]

The temperature compensation gain coefficient is used to scale DCGN when temperature drops

below the T

32) for each degree that temperature is below the T

TOFF[2:0]

The temperature compensation offset threshold sets the temperature above which there is no

temperature compensation applied to DCGN. This threshold is also used as the threshold for

application of cold temperature compensation of EDV1 (see GAF/EDVT section) and the threshold

to allow the NAC = LMD capacity adjustment to be made at IMIN detection (see Functional

Description section). The T

If PKCFG[0] = 1, the bqJUNIOR assumes a fixed value of 0x46 for TCOMP. This will increase the DCGN factor

identification byte. If TCOMP is updated using the UPCOMP host command (see Device Control section), the

value written by the host for TCOMP will be used regardless of the bit 0 value in PKCFG.

The bqJUNIOR has five power modes: Active, Sleep, Ship, Hibernate, and Data Retention (RBI). Figure 5

shows the flow that moves the device between the Active, Sleep, and Ship modes. Hibernate and Data

Retention are special modes not included in the flow. Detailed explanations of each mode follow the diagram in

Figure 5.

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