Datasheet

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Start Clock
Turn off clock
Convert Temperature
Input 2
Store Temperature
Input 2 in TEMP2
Register
Power up ADC
Power Down
Reference
Is Data
Averaging
Done
N
Y
Power Down ADC
DONE
Host Writes A/D
Converter Control
Register
Power Up Reference
(Including Delay)
Set /DAV = 0
OPERATION - BATTERY MEASUREMENT
TSC2301
SLAS371D – SEPTEMBER 2002 – REVISED AUGUST 2004
Temperature Input 2
Figure 63. Additional Temperature Measurement for Differential Temperature Reading
An added feature of the TSC2301 is the ability to monitor the battery voltage which may be much larger than the
supply voltage of the TSC2301. An example of this is shown in Figure 64 , where a battery voltage ranging up to
6 V may be regulated by a dc/dc converter or low-dropout regulator to provide a lower supply voltage to the
TSC2301. The battery voltage can vary from 0.5 V to 6 V while maintaining the voltage to the TSC2301 at a level
of 2.7 V-3.6 V. The input voltage on V
BAT1
is divided down by 4 so that a 6.0-V battery voltage is represented as
1.5 V to the A/D, while the input voltage on V
BAT2
is divided by 2 so that 3.0-V battery voltage is represented as
1.5 V to the A/D. If the battery voltage is low enough, the 1.2 V internal reference can be used to decrease LSB
size, potentially improving accuracy. The battery voltage on V
BAT1
must be below 4* V
REF
, and the voltage on
V
BAT2
must be below 2* V
REF
. Due to constraints of the internal switches, the input to the A/D after the voltage
divider cannot be above 1.5 V or V
REF
, whichever is lower. In order to minimize the power consumption, the
divider is only ON during the sampling of the battery input.
55