MAX8526 View Datasheet(PDF) - Maxim Integrated

Part Name

Description

MFG CO.

MAX8526

1.425V to 3.6V Input, 2A, 0.2V Dropout LDO Regulators

Maxim Integrated 

1.425V to 3.6V Input, 2A,

0.2V Dropout LDO Regulators

Operating Region and Power Dissipation

The maximum power dissipation depends on the ther-

mal resistance of the IC package and circuit board, the

temperature difference between the die junction and

ambient air, and the rate of airflow. The power dissipat-

ed in the device is P = IOUT x (VIN - VOUT).

The package features an exposed thermal pad on its

underside. This pad lowers the thermal resistance of

the package by providing a direct heat conduction

path from the die to the PC board.

Additionally, the ground pins (GND) perform the dual

function of providing an electrical connection to system

ground and channeling heat away. Connect the

exposed backside pad and GND to the system ground

using a large pad or ground plane, or multiple vias to

the ground-plane layer.

Applications Information

Capacitor Selection and

Regulator Stability

Capacitors are required at the MAX8526/MAX8527/

MAX8528 inputs and outputs for stable operation over

the full temperature range and with load currents up to

2A. Connect a 2.2µF capacitor between IN and ground

and a 10µF capacitor with low equivalent-series-resis-

tance (ESR) capacitor between OUT and ground for 2A

output current. The input capacitor (CIN) lowers the

source impedance of the input supply. If input-supply

source impedance is high, place a larger input capaci-

tor close to IN to prevent VIN sagging due to load tran-

sients. Smaller output capacitors can be used for output

currents less than 2A. Calculate COUT as follows:

COUT = IOUT(max)  (1µF / 200mA)

Noise, PSRR, and Transient Response

The MAX8526/MAX8527/MAX8528 are designed to

operate with low dropout voltages and low quiescent

currents, while still maintaining good noise, transient

response, and AC rejection. See the Typical Operating

Characteristics for a plot of Power-Supply Rejection

Ratio (PSRR) vs. Frequency. When operating from

noisy sources, improved supply-noise rejection and

transient response can be achieved by increasing the

values of the input and output bypass capacitors and

through passive filtering techniques. The MAX8526/

MAX8527/MAX8528 load-transient response graphs

(see the Typical Operating Characteristics) show two

components of the output response: a DC shift from the

output impedance due to the load current change, and

the transient response. A typical transient overshoot for

a step change in the load current from 20mA to 2A is

45mV. Use larger output ceramic capacitors greater

than 10µF up to 100µF to attenuate the overshoot.

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