General Description
The MAX8840/MAX8841/MAX8842 ultra-low-noise, lowdropout (LDO) linear regulators are designed to deliver
up to 150mA continuous output current. These regulators achieve a low 120mV dropout for 120mA load current. 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 external divider.
The MAX8840/MAX8841 are preset to a variety of voltages 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
1μF
C
IN
1μF
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.
MAX8840/MAX8841/MAX8842
Ultra-Low-Noise, High PSRR, Low-Dropout,
150mA Linear Regulators in µDFN
2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(VIN= V
OUT
+ 0.5V, TA = -40°C to +85°C, unless otherwise noted. CIN= 1µF, C
OUT
= 1µF, C
BP
= 10nF. Typical values are at +25°C;
the MAX8842 is tested with 2.45V output, unless otherwise noted.) (Note 1)
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
IN to GND .................................................................-0.3V to +7V
Output Short-Circuit Duration ............................................Infinite
OUT, SHDN to GND ......................................-0.3V to (IN + 0.3V)
FB, BP, N.C. to GND..................................-0.3V to (OUT + 0.3V)
Continuous Power Dissipation (T
A
= +70°C)
6-Pin µDFN (derate 2.1mW/°C above +70°C) .............0.168W
θ
JA
..................................................................................477°C/W
Operating Temperature Range ...........................-40°C to +85°C
Junction Temperature......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
Input Voltage Range V
IN
26V
I
OUT
= 1mA, TA = +25°C -1 +1
I
OUT
= 100µA to 80mA, TA = +25°C -2 +2Output Voltage Accuracy
I
OUT
= 100µA to 80mA -3 +3
%
Maximum Output Current I
OUT
150 mA
Current Limit I
LIM
OUT = 90% of nominal value 150 200 300 mA
V
OUT
≥ 3V, I
OUT
= 80mA 80 170
V
OUT
≥ 3V, I
OUT
= 120mA 120
2.5V ≤ V
OUT
< 3V, I
OUT
= 80mA 90 200
2.5V ≤ V
OUT
< 3V, I
OUT
= 120mA 135
2V ≤ V
OUT
< 2.5V, I
OUT
= 80mA 120 250
Dropout Voltage (Note 2)
2V ≤ V
OUT
< 2.5V, I
OUT
= 120mA 180
mV
I
OUT
= 0.05mA 40 90
Ground Current I
Q
VIN = V
OUT(nom)
- 0.1V, I
OUT
= 0mA 220 500
µA
Line Regulation V
LNR
VIN = (V
OUT
+ 0.5V) to 6V, I
OUT
= 0.1mA 0.001 %/V
Load Regulation V
LDRIOUT
= 1mA to 80mA 0.003 %/mA
TA = +25°C 0.003 1
Shutdown Supply Current I
SHDN
SHDN = 0V
T
A
= +85°C 0.05
µA
MAX8840 78
f = 1kHz, I
OUT
= 10mA
MAX8841/MAX8842 72
MAX8840 75
f = 10kHz, I
OUT
= 10mA
MAX8841/MAX8842 65
MAX8840 54
Ripple Rejection PSRR
f = 100kHz, I
OUT
= 10mA
MAX8841/ MAX8842 46
dB
MAX8840/MAX8841/MAX8842
Ultra-Low-Noise, High PSRR, Low-Dropout,
150mA Linear Regulators in µDFN
_______________________________________________________________________________________ 3
ELECTRICAL CHARACTERISTICS (continued)
(VIN= V
OUT
+ 0.5V, TA = -40°C to +85°C, unless otherwise noted. CIN= 1µF, C
OUT
= 1µF, C
BP
= 10nF. Typical values are at +25°C;
the MAX8842 is tested with 2.45V output, unless otherwise noted.) (Note 1)
Note 1: Limits are 100% tested at +25°C. Limits over operating temperature range are guaranteed by design.
Note 2: Dropout is defined as V
IN
- V
OUT
when V
OUT
is 100mV below the value of V
OUT
for V
IN
= V
OUT
+ 0.5V.
Note 3: Time needed for V
OUT
to reach 90% of final value.
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
MAX8840 11
f = 100Hz to 100kHz,
I
LOAD
= 10mA
MAX8841/MAX8842 230
MAX8840 13
Output Noise Voltage
(RMS)
f = 100Hz to 100kHz,
I
LOAD
= 80mA
MAX8841/MAX8842 230
µV
Shutdown Exit Delay R
LOAD
= 50Ω (Note 3) 300 µs
SHDN Logic-Low Level V
IN
= 2V to 6V 0.4 V
SHDN Logic-High Level V
IN
= 2V to 6V 1.5 V
TA = +25°C
SHDN Input Bias Current
V
IN
= 6V, SHDN = 0V or
6V
T
A
= +85°C 0.01
µA
TA = +25°C 0.006 0.1
FB Input Bias Current
(MAX8842)
V
IN
= 6V, V
FB
= 1.3V
T
A
= +85°C 0.01
µA
Thermal Shutdown 160 °C
Thermal-Shutdown
Hysteresis
10 °C
Typical Operating Characteristics
(VIN= V
OUT
+ 0.5V, CIN= 1µF, C
OUT
= 1µF, CBP= 10nF, TA= +25°C, unless otherwise noted.)
MAX8840
OUTPUT VOLTAGE vs. INPUT VOLTAGE
MAX8840 toc01
INPUT VOLTAGE (V)
OUTPUT VOLTAGE (V)
54321
0.5
1.0
1.5
2.0
2.5
3.0
3.5
0.0
06
I
OUT
= 150mA
I
OUT
= 0mA
MAX8840
OUTPUT VOLTAGE ACCURACY
vs. LOAD CURRENT
MAX8840 toc02
LOAD CURRENT (mA)
% DEVIATION (%)
125100755025
-0.4
-0.2
0
0.2
0.4
0.6
-0.6
0150
MAX8840
OUTPUT VOLTAGE ACCURACY
vs. TEMPERATURE
MAX8840 toc03
TEMPERATURE (°C)
% DEVIATION (%)
603510-15
-0.8
-0.6
-0.4
-0.2
0
0.2
0.4
0.6
0.8
1.0
-1.0
-40 85
I
OUT
= 1mA