© 2009 Microchip Technology Inc.

DS21663D-page 9

TC2054/2055/2186

3.0

PIN DESCRIPTIONS

The descriptions of the pins are listed in Table 3-1.

3.1

there is a large distance between the input supply and

the

LDO

regulator,

some

input

capacitance

is

necessary for proper operation. A 1 µF capacitor,

most applications.

3.2

Ground Terminal (GND)

Connect the unregulated input supply ground return to

GND. Also connect one side of the 1 µF typical input

decoupling capacitor close to this pin and one side of

3.3

Shutdown Control Input (SHDN)

The regulator is fully enabled when a logic-high is

applied to SHDN. The regulator enters shutdown when

a logic-low is applied to this input. During shutdown, the

output voltage falls to zero and the supply current is

reduced to 0.5 µA (maximum).

3.4

Out-of-Regulation Flag (ERROR)

The open-drain ERROR flag provides indication that

the regulator output voltage is not in regulation. The

ERROR pin will be low when the output is typically

below 5% of its specified value.

3.5

connect one side of the LDO output decoupling

TABLE 3-1:

PIN FUNCTION TABLE

Pin Number

Symbol

Description

Unregulated supply input.

2

GND

Ground terminal.

3SHDN

Shutdown control input. The regulator is fully enabled when a logic high is

applied to this input. The regulator enters shutdown when a logic low is applied

to this input. During shutdown, output voltage falls to zero, ERROR is open

circuited and supply current is reduced to 0.5 µA (maximum).

4

ERROR

out-of-tolerance by approximately -5%.

Regulated voltage output.