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Rainbow Electronics MAX8842 User Manual

General description, Applications, Features

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General Description

The MAX8840/MAX8841/MAX8842 ultra-low-noise, low-
dropout (LDO) linear regulators are designed to deliver
up to 150mA continuous output current. These regula-
tors achieve a low 120mV dropout for 120mA load cur-
rent. The MAX8840 uses an advanced architecture to
achieve ultra-low output voltage noise of 11µV

RMS

and

PSRR of 54dB at 100kHz.

The MAX8841 does not require a bypass capacitor,
hence achieving the smallest PC board area. The
MAX8842 output voltage can be adjusted with an exter-
nal divider.

The MAX8840/MAX8841 are preset to a variety of volt-
ages in the 1.5V to 4.5V range. Designed with a p-channel
MOSFET series pass transistor, the MAX8840/MAX8841/
MAX8842 maintain very low ground current (40µA).

The regulators are designed and optimized to work with
low-value, low-cost ceramic capacitors. The MAX8840
requires only 1µF (typ) of output capacitance for stability
with any load. When disabled, current consumption drops
to below 1µA.

The MAX8840/MAX8841/MAX8842 are available in a tiny
1mm x 1.5mm x 0.8mm µDFN.

Applications

Cellular and Cordless Phones
PDA and Palmtop Computers
Base Stations
Bluetooth Portable Radios and Accessories
Wireless LANs
Digital Cameras
Personal Stereos
Portable and Battery-Powered Equipment

Features

Space-Saving 1.0mm x 1.5mm x 0.8mm µDFN
11µV

RMS

Output Noise at 100Hz to 100kHz

Bandwidth (MAX8840)

78dB PSRR at 1kHz (MAX8840)
120mV Dropout at 120mA Load
Stable with 1µF Ceramic Capacitor for Any Load
Guaranteed 150mA Output
Only Need Input and Output Capacitors (MAX8841)
Output Voltages: 1.5V, 1.8V, 2.5V, 2.6V, 2.7V, 2.8V,

2.85V, 3V, 3.3V, 4.5V (MAX8840/MAX8841) and
Adjustable (MAX8842)

Low 40µA Ground Current
Excellent Load/Line Transient
Overcurrent and Thermal Protection

MAX8840/MAX8841/MAX8842

Ultra-Low-Noise, High PSRR, Low-Dropout,

150mA Linear Regulators in µDFN

________________________________________________________________ Maxim Integrated Products

1

μDFN

(1.5mm x 1.0mm)

TOP VIEW

GND

BP (MAX8840)
N.C. (MAX8841)
FB (MAX8842)

SHDN

1

2

3

6

4

OUT

5

N.C.

IN

MAX8840
MAX8841
MAX8842

Pin Configuration

Ordering Information

MAX8840

OUTPUT PRESET

1.5V TO 4.5V

IN

INPUT
2V TO 6V

OFF

SHDN

C

BP

10nF

C

OUT

1

μF

C

IN

1

μF

OUT

ON

BP

GND

Typical Operating Circuits

19-0629; Rev 1; 1/07

For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.

*xy is the output voltage code (see the Output Voltage Selector
Guide). Other versions between 1.5V and 4.5V are available in
100mV increments. Contact factory for other versions.

+Denotes lead-free package.

PART*

TEMP RANGE

PIN-PACKAGE

MAX8840ELTxy+T

-40°C to +85°C

6 µDFN-6
1.5mm x 1.0mm

MAX8841ELTxy+T

-40°C to +85°C

6 µDFN-6
1.5mm x 1.0mm

MAX8842ELT+T

-40°C to +85°C

6 µDFN-6
1.5mm x 1.0mm

Typical Operating Circuits continued at end of data sheet.

Output Voltage Selector Guide appears at end of data sheet.