Low-Voltage Detect

The detect circuit must activate whenever the supply voltage drops below the programmed level. In order to account for temperature and process variations, the trip levels are typically higher than the specified value, to provide some margin. For example, when 4.5V is selected, the detect output will typically ac- tivate when the supply drops below 4.7V.

14.2.1 Power Supply

VSPD powers the digital section resistor string and the comparators. VSPA powers the analog section resistor string and the bandgap voltage. Level shifters, where needed, are included inside the block.

Table 14−1.Typical Sub-Circuit Current Consumption

Sub−Ckt Current Consumption

Band Gap

20A

 

 

Compartors

2A

 

 

Resistor String

6A

 

 

Total

40A

 

 

Table 14−2.Comparator Specification

 

Comparator Parameters

50mV ± 2mV

Hysteresis at 2.5V

 

 

100mV ± 8mV

Hysteresis at 4.7V

 

 

26mV

Hysteresis at Each Terminal

 

 

400nS

Response Time for Slow Input

 

 

Table 14−3.Band Gap Parameters

Band Gap Parameters

Bandgap Voltage Reference

(min)

1.00V

 

 

 

Bandgap Voltage Reference

(typ)

1.22V

 

 

 

Bandgap Voltage Reference

(max)

1.50V

 

 

 

Minimum Supply Voltage

(VSPA)

1.50V

Bandgap Startup Time

(typ)

< 16S

 

 

 

Additional MSC1210 Hardware

14-3

 

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Image 177
Texas Instruments MSC1210 manual Power Supply, 1.Typical Sub-Circuit Current Consumption, 2.Comparator Specification