MAX883CSA データシートの表示（PDF） - Maxim Integrated

部品番号

コンポーネント説明

メーカー

MAX883CSA

5V/3.3V or Adjustable, Low-Dropout, Low IQ, 200mA Linear Regulators

Maxim Integrated 

5V/3.3V or Adjustable, Low-Dropout,

Low IQ, 200mA Linear Regulators

INPUT

VOLTAGE

CIN

O.1µF

IN

OUT

LBI

OFF

(STBY)

MAX882

MAX883

SET

MAX884

GND

( ) ARE FOR MAX882

R1 + R2

VOUT = VSET R2 , VSET = 1.20V

OUTPUT

VOLTAGE

R1

LOAD

R2

COUT

2.2µF

INPUT

VOLTAGE

R1

CIN

O.1µF R2

IN

OUT

LBI

MAX882

STBY

GND SET

OUTPUT

VOLTAGE

COUT

2.2µF

R1+ R2

VSTBY TRIP = VSTBY R2 , VSTBY = 1.20V

Figure 2. Adjustable Output Using External Feedback

Resistors

Foldback Current Limiting

The MAX882/MAX883/MAX884 also include a foldback

current limiter. It monitors and controls the pass transis-

tor’s gate voltage, estimating the output current and

limiting it to 430mA for output voltages above 0.8V and

(VIN - VOUT) > 0.7V. If the output voltage drops below

0.8V, implying a short-circuit condition, the output cur-

rent is limited to 170mA. The output can be shorted to

ground for 1 minute without damaging the device if the

package can dissipate (VIN x 170mA) without exceed-

ing TJ = +150°C. When the output is greater than 0.8V

and (VIN - VOUT) < 0.7V (dropout operation), no current

limiting is allowed, to provide maximum load drive.

Thermal Overload Protection

Thermal overload protection limits total power dissipa-

tion in the MAX882/MAX883/MAX884. When the junc-

tion temperature exceeds TJ =+160°C, the thermal

sensor sends a signal to the shutdown logic, turning off

the pass transistor and allowing the IC to cool. The

thermal sensor turns the pass transistor on again after

the IC’s junction temperature cools by 10°C, resulting in

a pulsed output during thermal overload conditions.

Thermal overload protection is designed to protect the

MAX882/MAX883/MAX884 if fault conditions occur. It is

not intended to be used as an operating mode.

Prolonged operation in thermal shutdown mode may

reduce the IC’s reliability. For continual operation, do

not exceed the absolute maximum junction temperature

rating of TJ = +150°C.

Figure 3. Setting an Undervoltage Lockout Threshold Using

STBY

Power Dissipation and Operating Region

Maximum power dissipation of the MAX882/MAX883/

MAX884 depends on the thermal resistance of the case

and circuit board, the temperature difference between

the die junction and ambient air, and the rate of

air flow. The power dissipation across the device is

P = IOUT (VIN - VOUT). The resulting power dissipation

is as follows:

P = (TJ − TA )

(θJB + θ BA )

where (TJ - TA) is the temperature difference between

the MAX882/MAX883/MAX884 die junction and the sur-

rounding air, θJB (or θJC) is the thermal resistance of

the package chosen, and θBA is the thermal resistance

through the printed circuit board, copper traces, and

other materials to the surrounding air.

The 8-pin small-outline package for the MAX882/

MAX883/MAX884 features a special lead frame with a

lower thermal resistance and higher allowable power

dissipation. This package’s thermal resistance package

is θJB = 53°C/W, compared with θJB = 110°C/W for an

8-pin plastic DIP package and θJB = 125°C/W for an 8-

pin ceramic DIP package.

_______________________________________________________________________________________ 9

Share Link: