MCP1790-3002ESLASHEB datasheet(16/34 Pages) MICROCHIP

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MCP1790/MCP1791

DS22075A-page 16

4.8

Output Current and Current

Limiting

The MCP1790/MCP1791 devices are tested and

ensured to supply a minimum of 70 mA of output

current.

The MCP1790/MCP1791 also incorporate an output

current limit foldback. When the regulator is in an

overcurrent condition, VOUT will decrease with increas-

ing load. When VOUT falls below 30% (typical) of VR,

the output current will start to fold back. The output

current will fold back to less than 100 mA (typical) when

VOUT is near 0 volts.

The 5.0V regulator has an overload current limiting of

approximately 120 mA. If VREG is lower than 3.5V, IOUT

will start to fold back and decrease along with VREG

until IOUT is less than 105 mA and VREG is near 0 volts.

The 3.3V regulator has an overload current limiting of

approximately 130 mA. If VREG is lower than 2.5V, IOUT

will start to fold back and decrease along with VREG

until IOUT is less than 99 mA and VREG is near 0 volts.

FIGURE 4-3:

ESR Curves For Load Capacitor Selection.

Load Capacitor [uF]

ESR Curves

0.1

0.01

0.001

100

1000

0.1

Instable

Stable only

with Tantalum or

Electrolytic cap.

Stable with

Tantalum,

Electrolytic and

Ceramic cap.

MCP1790-3002E/EB Datasheet(PDF) 16 Page - Microchip Technology