5

Application information

Figure 7. Typical application schematics using TSC1214

Table 5. External components list

Name

Value

Tolerance

Comments

RSHUNT

10 mΩ to 50 mΩ

1%

Shunt resistor to sense the current

ROSC

200 kΩ

0.1%

Internal oscillator bias resistor

C1

1 µF

-

Supply decoupling capacitance

5.1

Functional description

5.1.1

Digital current sensing

The TSC1214 is a current, voltage, and temperature digital monitor. The low-side bidirectional current is

measured through a shunt resistor placed between the IN pad and the ground. The current sense 14-bit ADC has

a 500 ms conversion time. The ADC output is in two’s complement format. When a conversion cycle is completed,

the value is stored in the REG_CURRENT registers (see Table 9), and can be read by the controller. Those

registers are updated at the end of each conversion.

5.1.2

Supply voltage and temperature monitoring

The power supply voltage and chip temperature (close to the load temperature) are measured by means of an 11-

bit ADC and a multiplexer. This takes place concurrently with the current sensing with a dedicated A/D converter,

which means that it does not affect the performance of the current sensing. To reduce the power consumption, a

conversion takes place only every two seconds, alternatively for load voltage and temperature (so each value is

refreshed every four seconds).

The conversion cycle time is 250 ms. The resolution is 2.44 mV for the power supply voltage and 0.125 °C for the

temperature.

When a conversion cycle is completed, the values are stored respectively in the REG_VOLTAGE and

REG_TEMPERATURE registers (see Table 9).

TSC1214

Application information

DS14731 - Rev 1

page 6/18