AVAILABLE
Functional Diagrams
Pin Configurations appear at end of data sheet.
Functional Diagrams continued at end of data sheet.
UCSP is a trademark of Maxim Integrated Products, Inc.
For pricing, delivery, and ordering information, please contact Maxim Direct
at 1-888-629-4642, or visit Maxim’s website at www.maximintegrated.com.
_______________General Description
The MAX603/MAX604 low-dropout, low quiescent cur-
rent, linear regulators supply 5V, 3.3V, or an adjustable
output for currents up to 500mA. They are available in a
1.8W SO package. Typical dropouts are 320mV at 5V
and 500mA, or 240mV at 3.3V and 200mA. Quiescent
currents are 15µA typ and 35µA max. Shutdown turns
off all circuitry and puts the regulator in a 2µA off mode.
A unique protection scheme limits reverse currents
when the input voltage falls below the output. Other fea-
tures include foldback current limiting and thermal
overload protection.
The output is preset at 3.3V for the MAX604 and 5V for
the MAX603. In addition, both devices employ Dual
Mode™ operation, allowing user-adjustable outputs
from 1.25V to 11V using external resistors. The input
voltage supply range is 2.7V to 11.5V.
The MAX603/MAX604 feature a 500mA P-channel
MOSFET pass transistor. This transistor allows the
devices to draw less than 35µA over temperature, inde-
pendent of the output current. The supply current
remains low because the P-channel MOSFET pass tran-
sistor draws no base currents (unlike the PNP transis-
tors of conventional bipolar linear regulators). Also,
when the input-to-output voltage differential becomes
small, the internal P-channel MOSFET does not suffer
from excessive base current losses that occur with sat-
urated PNP transistors.
________________________Applications
5V and 3.3V Regulators
1.25V to 11V Adjustable Regulators
Battery-Powered Devices
Pagers and Cellular Phones
Portable Instruments
Solar-Powered Instruments
____________________________Features
♦500mA Output Current, with Foldback Current
Limiting
♦High-Power (1.8W) 8-Pin SO Package
♦Dual Mode™ Operation: Fixed or Adjustable
Output from 1.25V to 11V
♦Large Input Range (2.7V to 11.5V)
♦Internal 500mA P-Channel Pass Transistor
♦15µA Typical Quiescent Current
♦2µA (Max) Shutdown Mode
♦Thermal Overload Protection
♦Reverse-Current Protection
______________Ordering Information
* Dice are tested at TA= +25°C, DC parameters only.
** Contact factory for availability.
5V/3.3V or Adjustable, Low-Dropout,
Low I
Q
, 500mA Linear Regulators
1
2
3
4
8
7
6
5
OUT
GND
GND
SET
IN
GND
GND
OFF
MAX603
MAX604
DIP/SO
TOP VIEW
__________________Pin Configuration
MAX603
MAX604
OUT
SETGND
IN
OFF COUT
10µF
CIN
10µF
BATTERY
OUTPUT
VOLTAGE
__________Typical Operating Circuit
19-0269; Rev 0; 9/94
PART
MAX603CPA
MAX603CSA
MAX603C/D 0°C to +70°C
0°C to +70°C
0°C to +70°C
TEMP. RANGE PIN-PACKAGE
8 Plastic DIP
8 SO
Dice*
MAX603EPA
MAX603ESA -40°C to +85°C
-40°C to +85°C 8 Plastic DIP
8 SO
MAX603MJA -55°C to +125°C 8 CERDIP**
MAX604CPA
MAX604CSA
MAX604C/D 0°C to +70°C
0°C to +70°C
0°C to +70°C 8 Plastic DIP
8 SO
Dice*
MAX604EPA
MAX604ESA -40°C to +85°C
-40°C to +85°C 8 Plastic DIP
8 SO
MAX604MJA -55°C to +125°C 8 CERDIP**
™ Dual Mode is a trademark of Maxim Integrated Products.
MAX603/MAX604
5V/3.3V or Adjustable, Low-Dropout,
Low I
Q
, 500mA Linear Regulators
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(VIN = 6V (MAX603) or 4.3V (MAX604), CIN = COUT = 10µF, OFF = VIN, SET = GND, TJ= TMIN to TMAX, unless otherwise noted.
Typical values are at TJ= +25°C.) (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.
Supply Voltage (IN or OUT to GND).......................-0.3V to +12V
Output Short-Circuit Duration..............................................1 min
Continuous Output Current...............................................600mA
SET, OFF Input Voltages...........................-0.3V to the greater of
(IN + 0.3V) or (OUT + 0.3V)
Continuous Power Dissipation (TA= +70°C)
Plastic DIP (derate 9.09mW/°C above +70°C) ............727mW
SO (derate 23.6mW/°C above +70°C).............................1.8W
CERDIP (derate 8.00mW/°C above +70°C).................640mW
Operating Temperature Ranges
MAX60_C_A........................................................0°C to +70°C
MAX60_E_A.....................................................-40°C to +85°C
MAX60_MJA ..................................................-55°C to +125°C
Junction Temperature......................................................+150°C
Storage Temperature Range.............................-65°C to +160°C
Lead Temperature (soldering, 10sec).............................+300°C
SET = OUT, RL= 1kΩ
VIN = 11.5V, SET = OUT
OFF ≤0.4V, RL= 1kΩ,
(VOUT + 1V) ≤VIN ≤11.5V
IOUT = 500mA
IOUT = 200mA
3.0V ≤VIN ≤11.5V, SET = OUT
IOUT = 1mA to 300mA
IOUT = 20µA to 500mA,
6.0V < VIN < 11.5V
IOUT = 20µA to 300mA,
4.3V < VIN < 11.5V
IOUT = 400mA
IOUT = 1mA to 500mA
IOUT = 200mA
mA
1200
ILIM
Foldback Current Limit
(Note 4) 350
µA
20
IOUT MIN
Minimum Load Current 6
2
µA
20
IQ OFF
OFF Quiescent Current 10
0.01 2
µA
40
IQ
Quiescent Current 15 35
mV
480 820
∆VDO
Dropout Voltage (Note 3) 240 410
V
3.0 11.5
VIN
Input Voltage 2.9 11.5
2.7 11.5
320 550
130 220 mV740∆V
LNR
Line Regulation
mV
30 100
∆VLDR
Load Regulation
4.75 5.00 5.25 V
3.15 3.30 3.45
VOUT
Output Voltage (Note 2)
60 100
150
UNITSMIN TYP MAXSYMBOLPARAMETER
VOUT > 0.8V and VIN - VOUT > 0.7V
VOUT < 0.8V
MAX60_M
MAX60_M
MAX60_E
MAX60_E
MAX60_C
MAX60_C
MAX60_M
MAX60_E
MAX60_C
MAX603
MAX60_M
MAX60_C/E
(VOUT + 0.5V) ≤VIN ≤11.5V, IOUT = 25mA
MAX604
MAX603
MAX604
MAX603C/E
MAX604
MAX603M
CONDITIONS
°C
10
160 °CThermal Shutdown Hysteresis TSD
Thermal Shutdown Temperature ∆TSD
MAX603/MAX604
2
Maxim Integrated
Note 1: Electrical specifications are measured by pulse testing and are guaranteed for a junction temperature (TJ) equal to the
operating temperature range. C and E grade parts may be operated up to a TJof +125°. Expect performance similar to
M grade specifications. For TJbetween +125°C and +150°C, the output voltage may drift more.
Note 2: (VIN - VOUT) is limited to keep the product (IOUT x (VIN - VOUT)) from exceeding the package power dissipation limits.
Note 3: Dropout Voltage is (VIN - VOUT) when VOUT falls to 100mV below its nominal value at VIN = VOUT + 2V. For example, the
MAX603 is tested by measuring the VOUT at VIN = 7V, then VIN is lowered until VOUT falls 100mV below the measured value.
The difference (VIN - VOUT) is then measured and defined as ∆VDO.
Note 4: Foldback Current Limit was characterized by pulse testing to remain below the maximum junction temperature.
Note 5: The Reverse-Current Protection Threshold is the output/input differential voltage (VOUT - VIN) at which reverse-current
protection switchover occurs and the pass transistor is turned off.
Note 6: Noise is tested using a bandpass amplifier with two poles at 10Hz and two poles at 10kHz.
5V/3.3V or Adjustable, Low-Dropout,
Low I
Q
, 500mA Linear Regulators
VOUT = 3.0V
VOUT = 4.5V
VIN = 11.5V, VOUT = 2V,
SET = OUT
VIN = 0V, VOUT = 4.5V (MAX603)
VOUT = 3.0V (MAX604)
µVRMS
250en
Output Noise (Note 6)
nA±0.01 ±10IOFF
OFF Input Leakage Current 4.0
VIH OFF
OFF Threshold Voltage 3.0
2.0 V
0.4
20
IOUT LKG
OUT Leakage Current 6 µA
0.01 2 nA±0.01 ±10ISET
SET Input Leakage Current V1.16 1.20 1.24VSET
SET Reference Voltage 150 80
VSET TH
Dual-Mode SET Threshold
µA
0.01 10
620
∆V
RTH mV
620
Reverse-Current Protection
Threshold (Note 5)
mV
80 30
tSTART
%VOUT
2VOSH
Start-Up Overshoot
20
100
UNITSMIN TYP MAXSYMBOLPARAMETER
10Hz to 10kHz, SET = OUT, RL= 1kΩ,
COUT = 10µF
VOFF = VIN or GND
MAX60_C
On, SET = OUT, VIN = 11.5V
On, SET = OUT, VIN = 6V
MAX604
On, SET = OUT, VIN = 4V
MAX603
Off MAX60_M
MAX60_E
For internal feedback
VIN = 9V, RL= 18Ω, VOFF switched from
0V to VIN, time from 0% to 95% of VOUT
MAX60_C
VSET = 1.5V or 0V
RL= 1kΩ, COUT = 10µF, OFF rise time ≤1µs
MAX60_E
MAX60_M
SET = OUT, RL= 1kΩ
For external feedback
CONDITIONS
ELECTRICAL CHARACTERISTICS (continued)
(VIN = 6V (MAX603) or 4.3V (MAX604), CIN = COUT = 10µF, OFF = VIN, SET = GND, TJ= TMIN to TMAX, unless otherwise noted.
Typical values are at TJ= +25°C.) (Note 1)
VIL OFF
Reverse Leakage Current IRVL
µs200Time Required to Exit Shutdown
MAX603/MAX604
Maxim Integrated
3
5V/3.3V or Adjustable, Low-Dropout,
Low I
Q
, 500mA Linear Regulators
__________________________________________Typical Operating Characteristics
(VIN = 7V for MAX603, VIN = 5.3V for MAX604, OFF= VIN, SET = GND, C IN = COUT = 10µF, R L= 1k Ω, TJ = +25°C, unless otherwise noted.)
1.00
1.01
0.95 0.1 10 700
OUTPUT VOLTAGE vs. LOAD CURRENT
0.96
MAX603/4-TOC-01
LOAD CURRENT (mA)
NORMALIZED OUTPUT VOLTAGE
0.97
0.98
0.99
1 100
VOUT = 3.3V, 5V, 10V
NORMALIZED TO
OUTPUT VOLTAGE
AT 1mA
25
30
00.1 10 700
QUIESCENT CURRENT vs. LOAD CURRENT
5
MAX603/4-TOC-02
LOAD CURRENT (mA)
QUIESCENT CURRENT (µA)
10
15
20
1 100
UPWARD CURVE IS
THERMAL EFFECT
MAX603, VIN = 12V, VOUT = 10V
MAX603, VIN = 7V, VOUT = 5V
MAX604, VIN = 5.3V, VOUT = 3.3V
02
OUTPUT VOLTAGE AND
QUIESCENT CURRENT vs. SUPPLY VOLTAGE
MAX1603/4 TOC-03
SUPPLY VOLTAGE (V)
OUTPUT VOLTAGE (V)
QUIESCENT CURRENT (µA)
8
4
2
46 12
6
3
1
5
10
3957 11
24
22
20
18
16
14
12
10
8
6
MAX603, VOUT = 5V
MAX604, VOUT = 3.3V
I
Q
, MAX604
I
Q
, MAX603
96
97
98
99
100
101
102
103
104
-55 45 125
OUTPUT VOLTAGE vs.
TEMPERATURE
MAX603/4-TOC-04
TEMPERATURE (°C)
NORMALIZED OUTPUT VOLTAGE (%)
5-35 856525-15 105
10ms/div
10Hz TO 10kHz OUTPUT NOISE
OUTPUT NOISE (1mV/div)
MAX603
VOUT = 5V
0
5
10
15
20
25
-55 45 125
QUIESCENT CURRENT vs.
TEMPERATURE
MAX603/4-TOC-05
TEMPERATURE (°C)
QUIESCENT CURRENT (µA)
5-35 856525-15 105
MAX603
MAX604
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
0 500
DROPOUT VOLTAGE vs. LOAD CURRENT
MAX603/4-TOC-06
LOAD CURRENT (mA)
DROPOUT VOLTAGE (V)
300100 700600400200
MAX604
VOUT = 3.3V
MAX603
VOUT = 5V
MAX603, VOUT = 10V,
SET EXTERNALLY
R
DS(ON)
= 0.4Ω
R
DS(ON)
= 0.65Ω
R
DS(ON)
= 1.2Ω
2ms/div
LINE-TRANSIENT RESPONSE
A: VIN = 8V (HIGH), VIN = 7V (LOW)
B: OUTPUT VOLTAGE (50mV/div)
A
B
MAX603
VOUT = 5V
tR = 10µs, tF = 70µs
MAX603/MAX604
4
Maxim Integrated
5V/3.3V or Adjustable, Low-Dropout,
Low I
Q
, 500mA Linear Regulators
2ms/div
LOAD-TRANSIENT RESPONSE
A: OUTPUT VOLTAGE (100mV/div)
B: IOUT = 500mA (HIGH), IOUT = 5mA (LOW)
A
B
MAX603
VOUT = 5V
_____________________________Typical Operating Characteristics (continued)
(VIN = 7V for MAX603, VIN = 5.3V for MAX604, OFF= VIN, SET = GND, C IN = COUT = 10µF, R L= 1k Ω, TJ = +25°C, unless otherwise noted.)
500µs/div
OVERSHOOT AND TIME
EXITING SHUTDOWN MODE
A: OFF PIN VOLTAGE (1V/div)
RISE TIME = 13µs
B: MAX603 OUTPUT VOLTAGE (1V/div)
DELAY = 4.936ms, OVERSHOOT = 1%, RISE TIME = 55µs
A
0V
5V
B
______________________________________________________________Pin Description
PIN NAME DESCRIPTION
1 IN Regulator Input. Supply voltage can range from 2.7V to 11.5V.
2, 3, 6, 7 GND Ground. These pins function as heatsinks, only in the SOIC package. All GND pins must be soldered to the
circuit board for proper power dissipation. Connect to large copper pads or planes to channel heat from the IC.
4OFF Shutdown, active low. Switch logic levels in less than 1µs with the high level above the OFF threshold.
5 SET Feedback for Setting the Output Voltage. Connect to GND to set the output voltage to the preselected 3.3V
or 5V. Connect to an external resistor network for adjustable output operation.
8 OUT Regulator Output. Fixed or adjustable from 1.25V to 11.0V. Sources up to 500mA for input voltages above 4V.
MAX603
MAX604
OUT
GND
GND
SET
IN
OFF
COUT
10µF
CIN
10µF
VIN
VOUT
GND
GND R1
R2
RL
1
2
3
4
8
7
6
5
Figure 1. Test Circuit
MAX603/MAX604
Maxim Integrated
5
_______________Detailed Description
The MAX603/MAX604 are low-dropout, low-quiescent-
current linear regulators designed primarily for battery-
powered applications. They supply an adjustable 1.25V
to 11V output or a preselected 5V (MAX603) or 3.3V
(MAX604) output for load currents up to 500mA. As
illustrated in Figure 2, they consist of a 1.20V reference,
error amplifier, MOSFET driver, P-channel pass transis-
tor, dual-mode comparator, and internal feedback volt-
age divider.
The 1.20V bandgap reference is connected to the error
amplifier’s inverting input. The error amplifier compares
this reference with the selected feedback voltage and
amplifies the difference. The MOSFET driver reads the
error signal and applies the appropriate drive to the P-
channel pass transistor. If the feedback voltage is lower
than the reference, the pass transistor gate is pulled
lower, allowing more current to pass and increasing the
output voltage. If the feedback voltage is too high, the
pass transistor gate is pulled up, allowing less current
to pass to the output.
The output voltage is fed back through either an internal
resistor voltage divider connected to the OUT pin, or an
external resistor network connected to the SET pin. The
dual-mode comparator examines the SET voltage and
selects the feedback path used. If SET is below 80mV,
internal feedback is used and the output voltage is regulat-
ed to 5V for the MAX603 or 3.3V for the MAX604.
Additional blocks include a foldback current limiter, reverse
current protection, thermal sensor, and shutdown logic.
Internal P-Channel Pass Transistor
The MAX603/MAX604 feature a 500mA P-channel
MOSFET pass transistor. This provides several advan-
tages over similar designs using PNP pass transistors,
including longer battery life.
The P-channel MOSFET requires no base drive, which
reduces quiescent current considerably. PNP based
regulators waste considerable amounts of current in
dropout when the pass transistor saturates. They also
use high base-drive currents under large loads. The
MAX603/MAX604 do not suffer from these problems
and consume only 15µA of quiescent current under
light and heavy loads, as well as in dropout.
5V/3.3V or Adjustable, Low-Dropout,
Low I
Q
, 500mA Linear Regulators
P
MOSFET DRIVER
WITH FOLDBACK
CURRENT LIMIT
THERMAL
SENSOR
SHUTDOWN
LOGIC
1.20V
REFERENCE DUAL-MODE
COMPARATOR
R1
R2
OUT
SET
REVERSE
CURRENT
PROTECTION
80mV
ERROR AMP
IN
OFF
GND
MAX603
MAX604
SHUTDOWN
Figure 2. Functional Diagram
MAX603/MAX604
6
Maxim Integrated
Output Voltage Selection
The MAX603/MAX604 feature dual-mode operation. In
preset voltage mode, the output of the MAX603 is set to
5V and the output of the MAX604 is set to 3.3V using
internal, trimmed feedback resistors. Select this mode
by connecting SET to ground.
In adjustable mode, an output between 1.25V and 11V
is selected using two external resistors connected as a
voltage divider to SET (Figure 3). The output voltage is
set by the following equation:
where VSET = 1.20V. To simplify resistor selection:
Since the input bias current at SET is nominally zero,
large resistance values can be used for R1 and R2 to
minimize power consumption without losing accuracy. Up
to 1.5MΩis acceptable for R2. Since the VSET tolerance
is less than ±40mV, the output can be set using fixed
resistors instead of trim pots.
In preset voltage mode, impedances between SET and
ground should be less than 10kΩ. Otherwise, spurious
conditions could cause the voltage at SET to exceed
the 80mV dual-mode threshold.
Shutdown
A low input on the OFF pin shuts down the MAX603/
MAX604. In the off mode, the pass transistor, control
circuit, reference, and all biases are turned off, reduc-
ing the supply current below 2µA. OFF should be con-
nected to IN for normal operation.
Use a fast comparator, Schmitt trigger, or CMOS or TTL
logic to drive the OFF pin in and out of shutdown. Rise
times should be shorter than 1µs. Do not use slow RC
circuits, leave OFF open, or allow the input to linger
between thresholds; these measures will prevent the
output from jumping to the positive supply rail in
response to an indeterminate input state.
Since the OFF threshold varies with input supply volt-
age (see
Electrical Characteristics
), do not derive the
drive voltage from 3.3V logic. With VIN at 11.5V, the
high OFF logic level needs to be above 4V.
Foldback Current Limiting
The MAX603/MAX604 also include a foldback current
limiter. It monitors and controls the pass transistor’s
gate voltage, estimating the output current and limiting
it to 1.2A for output voltages above 0.8V and VIN - VOUT
> 0.7V. For VIN - VOUT < 0.7V (dropout operation), there
is no current limit. If the output voltage drops below
0.8V, implying a short-circuit condition, the output cur-
rent is limited to 350mA. The output can be shorted to
ground for one minute without damaging the device if
the package can dissipate VIN x 350mA without
exceeding TJ= +150°C.
Thermal Overload Protection
Thermal overload protection limits total power dissipa-
tion in the MAX603/MAX604. When the junction temper-
ature exceeds TJ= +160°C, the thermal sensor sends a
signal to the shutdown logic, turning off the pass tran-
sistor and allowing the IC to cool. The thermal sensor
will turn the pass transistor on again after the IC’s junc-
tion temperature cools by 10°C, resulting in a pulsed
output during thermal overload conditions.
Thermal overload protection is designed to protect the
MAX603/MAX604 in the event of fault conditions. For
continual operation, the absolute maximum junction tem-
perature rating of TJ= +150°C should not be exceeded.
Operating Region and Power Dissipation
Maximum power dissipation of the MAX603/MAX604
depends on the thermal resistance of the case and cir-
cuit 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 maximum power dissipation is:
where (TJ- TA) is the temperature difference between
the MAX603/MAX604 die junction and the surrounding
P T - T
+
MAX JA
JB BA
=
()
()
θθ
R1 R2 V
V - 1
OUT
SET
=
V V1 R1
R2
OUT SET
=+
5V/3.3V or Adjustable, Low-Dropout,
Low I
Q
, 500mA Linear Regulators
MAX603
MAX604
OUT
SET
GND
IN
OFF COUT
10µF
CIN
0.1µF to
10µF
BATTERY
OUTPUT
VOLTAGE
R1
R2
RL
Figure 3. Adjustable Output Using External Feedback Resistors
MAX603/MAX604
Maxim Integrated
7
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 SOIC package for the
MAX603/MAX604 features a special lead frame with a
lower thermal resistance and higher allowable power
dissipation. The thermal resistance of this package is
θJB = 42°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.
The GND pins of the MAX603/MAX604 SOIC package
perform the dual function of providing an electrical con-
nection to ground and channeling heat away. Connect
all GND pins to ground using a large pad or ground
plane. Where this is impossible, place a copper plane
on an adjacent layer. The pad should exceed the
dimensions in Figure 4.
Figure 4 assumes the IC is an 8-pin SOIC package, is
soldered directly to the pad, has a +125°C maximum
junction temperature and a +25°C ambient air tempera-
ture, and has no other heat sources. Use larger pad
sizes for other packages, lower junction temperatures,
higher ambient temperatures, or conditions where the IC
is not soldered directly to the heat-sinking ground pad.
The MAX603/MAX604 can regulate currents up to
500mA and operate with input voltages up to 11.5V, but
not simultaneously. High output currents can only be
sustained when input-output differential voltages are
low, as shown in Figure 5. Maximum power dissipation
depends on packaging, board layout, temperature, and
air flow. The maximum output current is:
where PMAX is derived from Figure 4.
Reverse-Current Protection
The MAX603/MAX604 has a unique protection scheme
that limits reverse currents when the input voltage falls
below the output. It monitors the voltages on IN and
OUT and switches the IC’s substrate and power bus to
I
P T - T
V - V 100 C
OUT max MAX J A
IN OUT
()
=×
()
()
×°
5V/3.3V or Adjustable, Low-Dropout,
Low I
Q
, 500mA Linear Regulators
0
100
200
300
400
500
600
700
27
MAX604
MAX603/4-FIG-04B
SUPPLY VOLTAGE (V)
MAXIMUM OUTPUT CURRENT (mA)
53981012116413
CERAMIC DIP
PLASTIC DIP
HIGH-POWER SOIC
MAXIMUM SUPPLY VOLTAGE LIMIT
TYPICAL DROPOUT VOLTAGE LIMIT
MAXIMUM CONTINUOUS CURRENT LIMIT
OPERATING
REGION AT
TA = +25°C
TJ = +125°C
0
100
200
300
400
500
600
700
7
MAX603
MAXIMUM OUTPUT CURRENT vs. SUPPLY VOLTAGE
MAX603/4-FIG-04A
SUPPLY VOLTAGE (V)
MAXIMUM OUTPUT CURRENT (mA)
5981012116413
CERAMIC DIP
PLASTIC DIP
HIGH-POWER
SOIC
MAXIMUM SUPPLY VOLTAGE LIMIT
TYPICAL DROPOUT VOLTAGE LIMIT
MAXIMUM CONTINUOUS CURRENT LIMIT
OPERATING
REGION AT
TA = +25°C
TJ = +125°C
Figure 5. Power Operating Regions: Maximum Output Current
vs. Differential Supply Voltage
1.0 10.2 10 20
6.51.3 (in2)
(cm2)65 130
POWER DISSIPATION vs.
GROUND PAD AREA
1.2
MAX603/4 FIG 4
COPPER GROUND PAD AREA
POWER DISSIPATION (W)
1.4
1.6
1.8
1.1
1.3
1.5
1.7
MAX603, VOUT = 5V
8-PIN SO PACKAGE
PAPER EPOXY BOARD
SINGLE SIDED
1oz. COPPER
TJ = +125°C
TA = +25°C STILL AIR
Figure 4. Typical Maximum Power Dissipation vs. Ground Pad
Size.
MAX603/MAX604
8
Maxim Integrated
the more positive of the two. The control circuitry can
then remain functioning and turn the pass transistor off,
limiting reverse currents back through the device. This
feature allows a backup regulator or battery pack to
maintain VOUT when the supply at IN fails.
Reverse-current protection activates when the voltage
on IN falls 6mV (20mV maximum) below the voltage on
OUT. Before this happens, currents as high as several
milliamperes can flow back through the device. After
switchover, typical reverse currents are limited to
0.01µA for as long as the condition exists.
__________Applications Information
Figure 6 illustrates the typical application for the
MAX603/MAX604.
Capacitor Selection and
Regulator Stability
Normally, use 0.1µF to 10µF capacitors on the input
and 10µF on the output of the MAX603/MAX604. The
larger input capacitor values provide better supply-
noise rejection and line-transient response. Improve
load-transient response, stability, and power-supply
rejection by using large output capacitors. For stable
operation over the full temperature range and with load
currents up to 500mA, 10µF is recommended. Using
capacitors smaller than 3.3µF can result in oscillation.
Noise
The MAX603/MAX604 exhibit 3mVp-p to 4mVp-p of
noise during normal operation. This is negligible in most
applications. When using the MAX603/MAX604 in appli-
cations that include analog-to-digital converters of
greater than 12 bits, consider the ADC’s power-supply
rejection specifications. Refer to the output noise plot in
the
Typical Operating Characteristics
.
PSRR and Operation from Sources
Other than Batteries
The MAX603/MAX604 are designed to deliver low
dropout voltages and low quiescent currents in battery-
powered systems. Achieving these objectives requires
trading off power-supply noise rejection and swift
response to supply variations and load transients.
Power-supply rejection is 80dB at low freqencies and
rolls off above 10Hz. As the frequency increases above
10kHz, the output capacitor is the major contributor to
the rejection of power-supply noise (Figure 7). Do not
use power supplies with ripple above 100kHz, especial-
ly when the ripple exceeds 100mVp-p. When operating
from sources other than batteries, improved supply-
noise rejection and transient response can be achieved
by increasing the values of the input and output capaci-
tors, and through passive filtering techniques. The
Typical Operating Characteristics
show the MAX603/
MAX604 supply and load-transient responses.
Transient Considerations
The
Typical Operating Characteristics
show the
MAX603/MAX604 load-transient response. Two compo-
nents of the output response can be observed on the
load-transient graphs—a DC shift from the output imped-
ance due to the different load currents, and the transient
response. Typical transients for step changes in the load
current from 5mA to 500mA are 0.2V. Increasing the out-
put capacitor’s value attenuates transient spikes.
5V/3.3V or Adjustable, Low-Dropout,
Low I
Q
, 500mA Linear Regulators
MAX603
MAX604
OUT
SETGND
IN
OFF COUT
10µF
CINBATTERY
OUTPUT
VOLTAGE
50
60
0100101102103104105106
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY
10
MAX603/4-FIG-06
FREQUENCY (Hz)
PSRR (dB)
20
30
40
80
90
70 IOUT = 1mA
VIN = 1Vp-p
FOR f < 400kHz
CIN = 0µF
COUT = 10µF
IOUT = 100mA
Figure 6. 3.3V or 5V Linear-Regulator Application
Figure 7. Power-Supply Rejection Ratio vs. Ripple Frequency
MAX603/MAX604
Maxim Integrated
9
Input-Output (Dropout) Voltage
A regulator’s minimum input-output voltage differential,
or dropout voltage, determines the lowest usable supply
voltage. In battery-powered systems, this will determine
the useful end-of-life battery voltage. Because the
MAX603/MAX604 use a P-channel MOSFET pass tran-
sistor, their dropout voltage is a function of rDS(ON) multi-
plied by the load current (see
Electrical Characteristics
).
Quickly stepping up the input voltage from the dropout
voltage can result in overshoot. This occurs when the
pass transistor is fully on at dropout and the IC is not
given time to respond to the supply voltage change.
Prevent this by slowing the input voltage rise time.
5V/3.3V or Adjustable, Low-Dropout,
Low I
Q
, 500mA Linear Regulators
___________________Chip Topography
IN
0.100"
(2.54mm)
0.104"
(2.64mm)
OFF GND SET
OUT
TRANSISTOR COUNT: 111
NO DIRECT SUBSTRATE CONNECTION. THE N-SUBSTRATE
IS INTERNALLY SWITCHED BETWEEN THE MORE POSITIVE
OF IN OR OUT.
MAX603/MAX604
10
Maxim Integrated
5V/3.3V or Adjustable, Low-Dropout,
Low I
Q
, 500mA Linear Regulators
________________________________________________________Package Information
DIM
A
A1
A2
A3
B
B1
C
D1
E
E1
e
eA
eB
L
MIN
–
0.015
0.125
0.055
0.016
0.045
0.008
0.005
0.300
0.240
0.100
0.300
–
0.115
MAX
0.200
–
0.175
0.080
0.022
0.065
0.012
0.080
0.325
0.310
–
–
0.400
0.150
MIN
–
0.38
3.18
1.40
0.41
1.14
0.20
0.13
7.62
6.10
2.54
7.62
–
2.92
MAX
5.08
–
4.45
2.03
0.56
1.65
0.30
2.03
8.26
7.87
–
–
10.16
3.81
INCHES MILLIMETERS
P PACKAGE
PLASTIC
DUAL-IN-LINE
DIM
D
D
D
D
D
D
MIN
0.348
0.735
0.745
0.885
1.015
1.14
MAX
0.390
0.765
0.765
0.915
1.045
1.265
MIN
8.84
18.67
18.92
22.48
25.78
28.96
MAX
9.91
19.43
19.43
23.24
26.54
32.13
INCHES MILLIMETERS
PINS
8
14
16
18
20
24
C
AA2
E1
D
E
eA
eB
A3
B1
B
0° - 15°
A1
L
D1
e
DIM
A
A1
B
C
E
e
H
L
MIN
0.053
0.004
0.014
0.007
0.150
0.228
0.016
MAX
0.069
0.010
0.019
0.010
0.157
0.244
0.050
MIN
1.35
0.10
0.35
0.19
3.80
5.80
0.40
MAX
1.75
0.25
0.49
0.25
4.00
6.20
1.27
INCHES MILLIMETERS
21-0041A
S PACKAGE
SMALL
OUTLINE
DIM
D
D
D
MIN
0.189
0.337
0.386
MAX
0.197
0.344
0.394
MIN
4.80
8.55
9.80
MAX
5.00
8.75
10.00
INCHES MILLIMETERS
PINS
8
14
16
1.270.050
L
0°-8°
HE
D
e
A
A1 C
0.101mm
0.005in.
B
MAX603/MAX604
Maxim Integrated
11
5V/3.3V or Adjustable, Low-Dropout,
Low I
Q
, 500mA Linear Regulators
___________________________________________Package Information (continued)
C
0°-15°
AD
B1
B
DIM
A
B
B1
C
E
E1
e
L
L1
Q
S
S1
MIN
–
0.014
0.038
0.008
0.220
0.290
0.125
0.150
0.015
–
0.005
MAX
0.200
0.023
0.065
0.015
0.310
0.320
0.200
–
0.070
0.098
–
MIN
–
0.36
0.97
0.20
5.59
7.37
3.18
3.81
0.38
–
0.13
MAX
5.08
0.58
1.65
0.38
7.87
8.13
5.08
–
1.78
2.49
–
2.54 0.100
Q
L
S1
e
J PACKAGE
(0.300 in.)
CERDIP
DUAL-IN-LINE
S
L1
E
E1
PINS
8
14
16
18
20
24
DIM
D
D
D
D
D
D
MIN
–
–
–
–
–
–
MAX
0.405
0.785
0.840
0.960
1.060
1.280
MIN
–
–
–
–
–
–
MAX
10.29
19.94
21.34
24.38
26.92
32.51
INCHES MILLIMETERS
INCHES MILLIMETERS
MAX603/MAX604
12 Maxim Integrated 160 Rio Robles, San Jose, CA 95134 USA 1-408-601-1000
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied.
Maxim reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits) shown in the Electrical
Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance.
© 1994 Maxim Integrated The Maxim logo and Maxim Integrated are trademarks of Maxim Integrated Products, Inc.
