CS2082

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8

squib resistance) may be reported by the fault register and

should be ignored.

Power Dissipation during resistive measurement can be

calculated as:

P

+ ISQUIB(VBAT * VDIFF) * (ISQUIB

RMR)

The resultant increase in power dissipation will cause a

corresponding increase in die temperature which will cause

a corresponding decrease in time to thermal shutdown of the

CS2082. To minimize the impact of squib resistive

measurements on time to thermal shutdown a 5% duty cycle

is recommended.

Analog MUX – $4d

Analog Mux select register bit definitions are shown in

Table 6. All other states will be interpreted as High–Z. At

power–up, the default state is ‘High–Z.’

Table 6. Analog MUX Output Select

D3

D2

D1

D0

State

0

0

0

0

High–Z

0

0

0

1

MR

0

0

1

0

AIN

0

1

0

0

BAT

1

0

0

0

RES

Low Side Switch Control – $5d

The $5d command activates the low side switches. When

a data bit is low that switch is turned on. More than one

switch can be activated at a time. Bit assignment is shown in

Table 7. At power–up, no switches are active.

Table 7. Low Side Switch Select

D3

D2

D1

D0

Active

x

x

0

0

BOTH

x

x

0

1

SL2

x

x

1

0

SL1

x

x

1

1

NONE

Auxiliary Control Register – $6d

threshold. The threshold determines when the $1x Status

8. At power–up, default trip is 17 V.

D3

D2

D1

D0

Trip

x

x

x

0

17 V

x

x

x

1

23 V

High Side Switch Control – $Ad

The $Ad command activates the high side switches. When

a data bit is high, that switch is turned on. More than one

switch can be activated at a time. Bit assignment is shown in

Table 9. Note that the $5d and $Ad commands are binary

complements, i.e., by sending 1010xx11, both high side

switches are activated, and by sending the complement

0101xx00, both low side switches are activated. At

power–up, no switches are active.

Table 9. High Side Switch Select

D3

D2

D1

D0

Active

x

x

0

0

NONE

x

x

0

1

SH1

x

x

1

0

SH2

x

x

1

1

BOTH