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MAX8888
User Manual
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MAXIM MAX8887, MAX8888 User Manual

General Description
The MAX8887/MAX8888 low-dropout linear regulators operate from a 2.5V to 5.5V input and deliver up to 300mA continuous (500mA pulsed) current. The MAX8887 is optimized for low-noise operation, while the MAX8888 includes an open-drain POK ouput flag. Both regulators feature exceptionally low 100mV dropout at 200mA. These devices are available in a variety of pre­set output voltages in the 1.5V to 3.3V range.
An internal PMOS pass transistor allows the low 55µA supply current to remain independent of load, making these devices ideal for portable battery-powered equip­ment such as personal digital assistants (PDAs), cellu­lar phones, cordless phones, and notebook computers. Other features include a micropower shutdown mode, short-circuit protection, thermal shutdown protection, and an active-low open-drain power-OK (POK) output that indicates when the output is out of regulation. The MAX8887/MAX8888 are available in a thin 5-pin SOT23 package that is only 1mm high.
________________________Applications
Notebook Computers
Wireless Handsets
PDAs and Palmtop Computers
Digital Cameras
PCMCIA Cards
Hand-Held Instruments
Features
♦ Guaranteed 300mA Output Current (500mA for
Pulsed Loads)
♦ Low 100mV Dropout at 200mA Load
♦ POK Output (MAX8888)
♦ 42µV
RMS
Output Noise (MAX8887)
♦ Preset Output Voltages (1.5V, 1.8V, 2.85V, and
3.3V)
♦ 55µA No-Load Supply Current
♦ Thermal Overload and Short-Circuit Protection
♦ Foldback Output Current-Limit Protection
♦ 60dB PSRR at 1kHz
♦ 0.1µA Shutdown Current
♦ Thin 5-Pin SOT23 Package, 1mm High
MAX8887/MAX8888
Low-Dropout, 300mA Linear Regulators in SOT23
________________________________________________________________ Maxim Integrated Products 1
Pin Configurations
MAX8887 MAX8888
ON
OFF
INPUT
2.5V TO 5.5V IN
SHDN
GND
(BP)
POK
OUT
V
OUT
300mA
C
IN
2.2μF
C
OUT
2.2μF
C
BP
0.01μF
( ) ARE FOR MAX8887 ONLY.
Typical Operating Circuit
19-1859; Rev 3; 11/06
Ordering Information
*Other versions (xy) between +1.5 and +3.3V are available in
100mV increments. Contact factory for other versions. Minimum order quantity is 25,000 units.
+Denotes lead-free availability.
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.
查询MAX8887EZK15供应商
PART
M A X8 8 8 7 E Z K15+ T -40°C to +85°C 5 SOT23-5 ADQD
MAX8887EZK18+ T -40°C to +85°C 5 SOT23-5 ADPX
MAX8887EZK29+ T -40°C to +85°C 5 SOT23-5 ADPY
MAX8887EZK33+ T -40°C to +85°C 5 SOT23-5 ADPZ
MAX8887EZKxy+ T* -40°C to +85°C 5 SOT23-5 —
M A X8 8 8 8 E Z K15+ T -40°C to +85°C 5 SOT23-5 ADQE
MAX8888EZK18+ T -40°C to +85°C 5 SOT23-5 ADQA
MAX8888EZK29+ T -40°C to +85°C 5 SOT23-5 ADQB
MAX8888EZK33+ T -40°C to +85°C 5 SOT23-5 ADQC
MAX8888EZKxy+ T* -40°C to +85°C 5 SOT23-5 —
TEMP
RANGE
PIN­PACKAGE
MARK
TOP
TOP VIEW
15OUTIN
MAX8887
2
GND
34
BPSHDN
15OUTIN
MAX8888
2
GND
34
POKSHDN
MAX8887/MAX8888
Low-Dropout, 300mA Linear Regulators in SOT23
2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(VIN= V
OUT
+ 1V, SHDN = IN, TA = -40°C to +85°C, 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, SHDN, POK, to GND...........................................-0.3V to +7V
OUT, BP to GND ............................................-0.3 to (V
IN
+ 0.3V)
Output Short-Circuit Duration.....................................Continuous
Continuous Power Dissipation (T
A
= +70°C)
5-Pin SOT23 (derate 9.1mW/°C above +70°C)............727mW
Operating Temperature Ranges..........................-40°C to +85°C
Junction Temperature......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+500°C
Input Voltage V
Input Undervoltage Lockout
Output Voltage Accuracy
Maximum Output Current
Current Limit
Ground-Pin Current
Dropout Voltage (Note 2) V
Line Regulation
Output Noise
PSRR
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
IN
V
rising
IN
(2% typical hysteresis)
TA = +25°C, I
I
= 100µA to 300mA,
OUT
= 0°C to +85°C
T
A
= 100µA to 300mA -3 +3
I
OUT
Continuous 300
10ms pulse 500
V
= 0
OUT
> 93% of nominal value 420
V
OUT
No load 55 100
= 300mA 65
I
OUT
= +3.3V
OUT
V
= 2.5V or (V
IN
I
= 5mA
OUT
MAX8887
MAX8888
MAX8887
MAX8888
2.5 5.5 V
2.15 2.4 V
= 100mA -1.2 +1.2
OUT
-2 +2
300
I
= 1mA
OUT
I
= 200mA 100 200
OUT
I
= 300mA 150
OUT
+ 0.4V) to 5.5V,
OUT
10Hz to 100kHz, C C
= 2.2µF, ESR
OUT
10Hz to 100kHz, C ESR
f < 1kHz, C C
OUT
f < 1kHz, C ESR
< 0.1Ω
COUT
= 0.01µF,
BP
= 4.7µF, ESR
OUT
< 0.1Ω
COUT
= 2.2µF,
= 0.01µF,
BP
COUT
= 2.2µF,
OUT
COUT
-0.15 0 0.15 %/V
< 0.1Ω
< 0.1Ω
0.5
42
360
60
40
µV
%
mA
mA
µA
mV
RMS
dB
MAX8887/MAX8888
Low-Dropout, 300mA Linear Regulators in SOT23
_______________________________________________________________________________________ 3
ELECTRICAL CHARACTERISTICS (continued)
(VIN= V
OUT
+ 1V, SHDN = IN, TA = -40°C to +85°C, unless otherwise noted.) (Note 1)
Note 1: All parts are 100% tested at T
A
= +25°C. Limits over the operating temperature range are guaranteed by design.
Note 2: Typical and maximum dropout voltage for different output voltages are shown in the Typical Operating Characteristics
curve.
Typical Operating Characteristics
(Typical Operating Circuit, TA = +25°C, unless otherwise noted.)
0
1.0
0.5
2.0
1.5
3.0
2.5
3.5
2.0 3.0 3.52.5 4.0 4.5 5.0 5.5
OUTPUT VOLTAGE vs. INPUT VOLTAGE
MAX8887/8 toc01
INPUT VOLTAGE (V)
OUTPUT VOLTAGE (V)
I
OUT
= 0
I
OUT
= 300mA
-1.0
-0.6
-0.8
0.0
-0.2
-0.4
0.2
0.4
0.8
0.6
1.0
10050 150 200 250 300
OUTPUT VOLTAGE ACCURACY
vs. LOAD CURRENT
MAX8887/8 toc02
LOAD CURRENT (mA)
% DEVIATION (%)
0
-0.05
-0.02
-0.03
-0.04
-0.01
0.0
0.01
0.02
0.03
0.04
0.05
-40 10-15 35 60 85
OUTPUT VOLTAGE ACCURACY
vs. TEMPERATURE
MAX8887/8 toc03
TEMPERATURE (°C)
% DEVIATION
I
OUT
= 0
V
IN
= V
OUT
+ 500mV
SHUTDOWN
Shutdown Supply Current SHDN = GND, VIN = 5.5V 0.1 2 µA
SHDN Input Threshold
SHDN Input Bias Current SHDN = IN or GND 10 100 nA
OUT Discharge Resistance in Shutdown
POK (MAX8888 ONLY)
POK Trip Level, Referred to OUT Set Point
Operating IN Voltage Range for Valid POK
POK Output Voltage Low V
POK Output Leakage Current V
THERMAL PROTECTION
Thermal Shutdown Temperature 170 °C
Thermal Shutdown Hysteresis 20 °C
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
V
V
2.5V ≤ VIN ≤ 5.5V 1.6
IH
2.5V ≤ VIN ≤ 5.5V 0.6
IL
SHDN = GND 650 1100 Ω
V
falling
OUT
(1% typical hysteresis)
90 92.5 95 %
1.0 5.5 V
I
OL
= 1mA 0.1 V
SINK
= 5.5V, SHDN = IN 100 nA
POK
V
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