MAXIM MAX1658ESA

19-1263; Rev 0; 7/97
350mA, 16.5V Input,
Low-Dropout Linear Regulators
The MAX1658/MAX1659 feature a 1µA shutdown mode,
reverse battery protection, short-circuit protection, and
thermal shutdown. They are available in a special highpower (1.2W), 8-pin SO package designed specifically
for compact applications.
____________________________Features
♦ Wide Input Voltage Range: 2.7V to 16.5V
♦ Low, 490mV Dropout at 350mA Output Current
(MAX1659)
♦ 30µA Supply Current
♦ 1µA Max Shutdown Current
♦ High-Power (1.2W) 8-Pin SO Package
♦ Dual Mode Operation Output:
Fixed 3.3V (MAX1658)
Fixed 5.0V (MAX1659)
or Adjustable (1.25V to 16V)
♦ Thermal Overload Protection
♦ Current-Limit Protection
♦ Reverse Battery Protection
________________________Applications
Digital Cordless Phones
______________Ordering Information
PCS Phones
Cellular Phones
PART
TEMP. RANGE
PIN-PACKAGE
PCMCIA Cards
MAX1658C/D
0°C to +70°C
Dice*
Modems
MAX1658ESA
-40°C to +85°C
8 SO
Hand-Held Instruments
Palmtop Computers
MAX1659C/D
0°C to +70°C
Dice*
MAX1659ESA
-40°C to +85°C
8 SO
*Dice are tested at TA = +25°C, DC parameters only.
Electronic Planners
__________Typical Operating Circuit
OUTPUT
3.3V OR 5V,
OR ADJ. (DOWN TO 1.25V);
UP TO 350mA
INPUT
UP TO 16.5V
IN
__________________Pin Configuration
TOP VIEW
OUT
MAX1658
MAX1659
SET
1
SHDN
2
ON
OFF
IN
SHDN
3
MAX1658
MAX1659
OUT 4
GND
8
GND
7
IN
6
IN
5
OUT
SET
SO
Dual Mode is a trademark of Maxim Integrated Products.
________________________________________________________________ Maxim Integrated Products
1
For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800.
For small orders, phone 408-737-7600 ext. 3468.
MAX1658/MAX1659
_______________General Description
The MAX1658/MAX1659 linear regulators maximize battery life by combining ultra-low supply currents and low
dropout voltages. They feature Dual Mode™ operation,
which presets the output to 3.3V (MAX1658) or 5V
(MAX1659), or permits it to be adjusted between 1.25V
and 16V. The regulator supplies up to 350mA, with a
typical dropout of 650mV for the MAX1658 and 490mV
for the MAX1659. With their P-channel MOSFET pass
transistor, these devices maintain a low quiescent current from zero output current to the full 350mA, even in
dropout. They support input voltages ranging from 2.7V
to 16.5V.
MAX1658/MAX1659
350mA, 16.5V Input,
Low-Dropout Linear Regulators
ABSOLUTE MAXIMUM RATINGS
IN to GND ................................................................-17V to +17V
Continuous Output Current ...............................................500mA
Output Short-Circuit Duration ............................................Infinite
SET, SHDN to GND .................................................-17V to +17V
OUT to GND ................................................-0.3V to (VIN + 0.3V)
Continuous Power Dissipation (Note 1)
SO (derate 14.5mW/°C above +70°C) .............................1.2W
Operating Temperature Range
MAX1658ESA/MAX1659ESA ............................-40°C to +85°C
Junction Temperature ......................................................+150°C
Storage Temperature Range .............................-65°C to +160°C
Lead Temperature Range (soldering, 10sec)..................+300°C
Note 1: See Operating Region and Power Dissipation section.
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.
ELECTRICAL CHARACTERISTICS
(VIN = 5V (MAX1658), VIN = 6V (MAX1659); COUT = 10µF; SHDN = IN; TA = TMIN to TMAX; unless otherwise noted. Typical values are
at TA = +25°C.) (Note 2)
PARAMETER
Input Voltage Range
Output Voltage
SYMBOL
VIN
VOUT
Regulated Output
Voltage Range
Maximum Output Current
Current Limit
Supply Current
CONDITIONS
SET = OUT
MIN
MAX1658,
5V ≤ VIN ≤ 16.5V
SET = GND,
0mA < ILOAD < 350mA MAX1659,
6V ≤ VIN ≤ 16.5V
(Note 3)
4.85
5.00
5.15
V
350
30
Load Regulation
∆VLDR
Startup Overshoot
VOSH
en
IOUT = 350mA
V
mA
IQ
∆VLNR
Output Noise
16
900
Line Regulation
V
3.40
ILIM
∆VDO
UNITS
16.5
3.30
1.25
IOUT(MAX)
MAX
3.20
IOUT = 1mA
Dropout Voltage (Note 4)
TYP
2.7
mA
60
µA
mV
2
MAX1658
650
1500
MAX1659
490
875
MAX1658, VIN = 5V to 16.5V
0.03
MAX1659, VIN = 6V to 16.5V
0.05
IOUT = 0mA to 350mA
0.003
%/mA
0
%VOUT
2.5
mVp-p
10Hz to 100kHz
%/V
SHUTDOWN
Logic-Low Input
VINLSHDN
2.7V ≤ VIN ≤ 16.5V
Logic-High Input Threshold
VINHSHDN
2.7V ≤ VIN ≤ 16.5V
Shutdown Input Bias Current
ISHDN
SHDN = GND or SHDN = IN
0.4
2.0
V
0.1
Shutdown Supply Current
IQSHDN
SHDN ≤ 0.4V
0.1
Shutdown Exit Time
tSTART
VOUT = 5.0V
120
2
V
_______________________________________________________________________________________
µA
1
µA
µs
350mA, 16.5V Input,
Low-Dropout Linear Regulators
(VIN = 5V (MAX1658), VIN = 6V (MAX1659); COUT = 10µF; SHDN = IN; TA = TMIN to TMAX; unless otherwise noted. Typical values are
at TA = +25°C.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
1.174
V
SET INPUT
SET Reference Voltage
VSET
SET Input Leakage Current
ISET
IOUT = 10µA (Note 3)
1.210
1.246
TA = +25°C (Note 3)
0.01
0.025
TA = +85°C (Note 3)
0.1
µA
THERMAL PROTECTION
Thermal Shutdown Temperature
Thermal Shutdown Hysteresis
TSD
165
°C
∆TSD
10
°C
Note 2: Specifications to -40°C are guaranteed by design, not production tested.
Note 3: Adjustable configuration only. VIN = 16.5V.
Note 4: The dropout voltage is defined as (VIN - VOUT) when VOUT is 100mV below the value of VOUT for VIN = VOUT + 2V.
__________________________________________Typical Operating Characteristics
(VIN = 5V (MAX1658), VIN = 6V (MAX1659); SHDN = IN; SET = GND; CIN = 0.1µF; COUT = 10µF tantalum; TA = +25°C; unless
otherwise noted.)
MAX1658
POWER-SUPPLY
REJECTION RATIO vs. FREQUENCY
-16
-24
-40
-32
PSSR (dB)
-30
-50
-40
-60
-48
-70
-56
VIN = 5.2V TO 5.4V
VOUT = 3.3V
-80
MAX1658 TOC03
-20
PSRR (dB)
-8
MAX1658 TOC01
-10
MAX1659
POWER-SUPPLY
REJECTION RATIO vs. FREQUENCY
VIN = 6.15V TO 6.4V
VOUT = 5V
-64
-90
-72
10
100
1000
FREQUENCY (Hz)
10k
100k
10
100
1000
10k
100k
FREQUENCY (Hz)
_______________________________________________________________________________________
3
MAX1658/MAX1659
ELECTRICAL CHARACTERISTICS (continued)
____________________________Typical Operating Characteristics (continued)
(VIN = 5V (MAX1658), VIN = 6V (MAX1659); SHDN = IN; SET = GND; CIN = 0.1µF; COUT = 10µF tantalum; TA = +25°C; unless
otherwise noted.)
NORMALIZED OUTPUT VOLTAGE
vs. LOAD CURRENT
0.994
3.3V OUTPUT
60
IL = 100mA
40
IL = 0mA
20
0.992
140
MAX1658/59 TOC09
MAX1658/59 TOC06
VOUT = 3.3V
120
QUIESCENT CURRENT (µA)
5V OUTPUT
80
SUPPLY CURRENT (µA)
MAX1658/59 TOC05
100
80
60
40
20
0.990
0
0
100
200
300
400
0
3
6
9
12
15
0
18
50
100
150 200 250 300
350 400
OUTPUT CURRENT (mA)
INPUT VOLTAGE (V)
LOAD CURRENT (mA)
DROPOUT VOLTAGE
vs. OUTPUT VOLTAGE
DROPOUT VOLTAGE
vs. LOAD CURRENT
MAX1658
LINE-TRANSIENT RESPONSE
MAX1658/59 TOC07
2000
1500
1000
500
MAX1658/59TOC11
800
700
DROPOUT VOLTAGE (mV)
0
MAX1658/59 TOC08
OUTPUT VOLTAGE VNOMINAL/VOUT (V)
0.998
0.996
QUIESCENT CURRENT
vs. LOAD CURRENT
MAX1658
SUPPLY CURRENT vs. INPUT VOLTAGE
1.000
DROPOUT VOLTAGE (mV)
MAX1658/MAX1659
350mA, 16.5V Input,
Low-Dropout Linear Regulators
600
A
VOUT = 3.3V
500
400
300
B
VOUT = 5.0V
200
100
IL = 350mA
VOUT = 3.3V
0
0
0
3
6
9
12
0
15
100
200
300
OUTPUT VOLTAGE (V)
LOAD CURRENT (mA)
MAX1659
LINE-TRANSIENT RESPONSE
MAX1658
LOAD-TRANSIENT RESPONSE
MAX1658/59TOC10
A
400
100µs/div
A: INPUT VOLTAGE (1V/div), VIN = 6V (HIGH), VIN = 5V (LOW)
B: OUTPUT VOLTAGE (100mV/div)
MAX1659
LOAD-TRANSIENT RESPONSE
MAX1658/59TOC12
MAX1658/59TOC13
A
A
B
B
B
VOUT = 5.0V
VOUT = 3.3V
100µs/div
A: INPUT VOLTAGE (1V/div), VIN = 7V (HIGH), VIN = 6V (LOW)
B: OUTPUT VOLTAGE (100mV/div)
4
200µs/div
A: OUTPUT VOLTAGE (100mV/div)
B: IOUT = 300mA (HIGH), IOUT = 40mA (LOW)
VOUT = 5V
200µs/div
A: OUTPUT VOLTAGE (100mV/div)
B: IOUT = 300mA (HIGH), IOUT = 40mA (LOW)
_______________________________________________________________________________________
350mA, 16.5V Input,
Low-Dropout Linear Regulators
MAX1659 OVERSHOOT AND
TIME EXITING SHUTDOWN
MAX1658 OVERSHOOT AND
TIME EXITING SHUTDOWN
MAX1658/59TOC15
MAX1658/59TOC14
3.3V
5V
0V
A
0V
A
B
B
100µs/div
100µs/div
A: OUTPUT VOLTAGE (2V/div)
B: SHDN PIN VOLTAGE (2V/div)
A: OUTPUT VOLTAGE (1V/div)
B: SHDN PIN VOLTAGE (2V/div)
OUTPUT NOISE DENSITY
vs. FREQUENCY
OUTPUT NOISE
MAX1658 TOC02
OUTPUT NOISE DENSITY (nVRMS/√Hz)
104
103
102
VOUT = 5V
IOUT = 165mA
10
10
10ms/div
50k
FREQUENCY (Hz)
10Hz TO 100kHz NOISE, VOUT = 5V (1mV/div), IOUT = 165mA
______________________________________________________________Pin Description
PIN
NAME
FUNCTION
1
SET
Output Voltage Input. Connecting SET to ground selects the factory-preset 3.3V (MAX1658) or 5V
(MAX1659) output voltage. For an adjustable output voltage, connect SET to a resistive voltage divider from
OUT to GND.
2
SHDN
3, 6, 7
IN
Unregulated Input Supply Voltage, 2.7V to 16.5V input range. The IN pins also serve as heatsinks. Connect
to a copper plane to achieve maximum thermal dissipation.
4, 5
OUT
Regulated Output Voltage. Fixed or adjustable from 1.25V to 16V. Sources up to 350mA. For stable operation, bypass with a 10µF, low-ESR (<0.2Ω) capacitor from OUT to GND. For improved load-transient
response, use a larger low-ESR capacitor.
8
GND
Ground
Shutdown Input. When SHDN is low, the device turns off and typically draws 0.1µA of supply current.
_______________________________________________________________________________________
5
MAX1658/MAX1659
____________________________Typical Operating Characteristics (continued)
(VIN = 5V (MAX1658), VIN = 6V (MAX1659); SHDN = IN; SET = GND; CIN = 0.1µF; COUT = 10µF tantalum; TA = +25°C; unless
otherwise noted.)
MAX1658/MAX1659
350mA, 16.5V Input,
Low-Dropout Linear Regulators
IN
SHDN
P
1.21V
REFERENCE
ERROR
AMPLIFIER
THERMAL
SENSOR
MOSFET
DRIVER
WITH
CURRENT
LIMIT
P
OUT
R1
SET
R2
DUAL-MODE
COMPARATOR
MAX1658
MAX1659
65mV
GND
Figure 1. Functional Diagram
_______________Detailed Description
The MAX1658/MAX1659 are micropower, low-dropout
linear regulators featuring Dual Mode™ operation,
which allows them to deliver an adjustable (1.25V to
16.5V) or preset (3.3V for the MAX1658, 5V for
MAX1659) output. They supply up to 350mA while
requiring only 120µA of supply current (typically 30µA
with no load). The devices include thermal shutdown
circuitry, output current limiting, a P-channel pass transistor, a Dual Mode comparator, and a feedback voltage divider. Figure 1 shows the functional diagram.
The 1.21V reference is connected to the amplifier’s
inverting input. The error amplifier compares this reference with the selected feedback voltage and amplifies
6
the difference. The error signal applies the drive to the
P-channel pass transistor. If the feedback voltage is
lower than the reference voltage, the transistor’s gate is
pulled lower, increasing output current.
The output voltage is fed back through an internal
resistor network or an external user-selected network.
The Dual Mode comparator examines the voltage at the
SET pin and selects either the internal or external feedback path. If SET is below 65mV, internal feedback sets
the MAX1658’s output voltage to 3.3V and the
MAX1659’s to 5V. Otherwise, external feedback is used
for an adjustable output between 1.25V and 16.5V.
Additional features include internal current limiting,
reverse battery protection, thermal-overload protection,
and a 1µA shutdown mode.
_______________________________________________________________________________________
350mA, 16.5V Input,
Low-Dropout Linear Regulators
ogy of a typical circuit operating in adjustable mode.
The output voltage is set by the following equation:

R1 
VOUT = VSET 1 +

R2 

where VSET = 1.21V. Solving for R1 yields:
V

R1 = R2  OUT − 1
V
 SET

Output Voltage Selection
Dual Mode operation allows the MAX1658/MAX1659 to
operate at either a preset or a user-adjustable output
voltage. The device compares the SET pin voltage with
an internal 65mV reference. If the voltage is lower than
65mV (typically achieved by grounding SET), the
device switches to an internal resistor-divider feedback
network that sets the output voltage. The MAX1658’s
preset output voltage is 3.3V and the MAX1659’s is 5V
(Figure 2).
If the SET pin is not below 65mV, the device switches to
external feedback and SET becomes a feedback input.
The feedback network can be configured to produce
an output between 16V and the voltage reference
(nominally 1.21V). Under regulation, the feedback
mechanism adjusts the error signal such that the voltage at the SET pin equals the reference voltage.
Therefore, to achieve the minimum output, connect SET
directly to OUT. For other voltages, a resistive voltagedivider network is necessary. Figure 3 shows the topol-
ON
OFF
INPUT
VOLTAGE
2
3, 6, 7
SHDN
OUT
4, 5
OUTPUT VOLTAGE
3.3V/350mA
(5V/350mA)
The input leakage current of the SET input is less than
25nA. This allows the use of large resistors in the feedback network to minimize output current loss without
compromising accuracy. R2 can be as high as 500kΩ
in most applications.
Shutdown
A logic low on the SHDN pin places the MAX1658/
MAX1659 in shutdown. This mode deactivates all functions, including the pass transistor. The device consumes less than 1µA of supply current in shutdown,
and its output becomes high impedance. The
MAX1658/MAX1659 exit shutdown in 100µs.
Output Current Limit
The MAX1658/MAX1659 include current-limiting circuitry that monitors and controls the pass transistor and
limits output current to around 900mA. The output can
be shorted to ground indefinitely without damaging the
device.
INPUT
VOLTAGE
3, 6, 7
2
MAX1658
(MAX1659)
IN
MAX1658
MAX1659
OUT
R1
SHDN
SET
IN
OUTPUT
VOLTAGE
4, 5
1
COUT
10µF
10µF
R2
0.1µF
0.1µF
GND
SET
GND
8
1
8
(
VOUT = VSET 1 + R1
R2
)
VSET = 1.21V
Figure 2. Preset Output Configuration
Figure 3. Adjustable Output Configuration Using External
Feedback Resistors
_______________________________________________________________________________________
7
MAX1658/MAX1659
P-Channel Pass Transistor
The MAX1658/MAX1659 feature an internal P-channel
MOSFET pass transistor. Using a MOSFET provides
several advantages over similar PNP designs, including
lower dropout voltage and extended battery life. Unlike
bipolar transistors, MOSFETs reduce quiescent current,
because they require no base current, particularly at
heavy loads and in dropout. As a result, the
MAX1658/MAX1659 operate at a low quiescent current
even in dropout.
Thermal-Overload Protection
Thermal-overload protection limits total power dissipation in the MAX1658/MAX1659. When the junction temperature exceeds TJ = +165°C, the pass transistor
deactivates, allowing the IC to cool. Once it has cooled
by 10°C, the control logic will enable operation. Under
thermal overload, the output of the device will pulse as
the die heats up and then cools to operational levels.
Prolonged operation under these conditions is not recommended.
Operating Region and Power Dissipation
Maximum power dissipation of the MAX1658/MAX1659
depends on the thermal resistance of the package and
circuit board, the temperature difference between the
die and ambient air, and the rate of air flow. The power
dissipation by the device is P = IOUT (VIN - VOUT). The
maximum power dissipation is:
(
)
 TJ − TA
PMAX = 
 θ
 JB + θBA
(
)



where (TJ - TA) is the temperature difference between
MAX1658/MAX1659 die junction and the surrounding
air, θJB is the thermal resistance of the package, and
θBA is the thermal resistance through the printed circuit
board, copper traces, and other materials to the
surrounding air. The 8-pin SO package for the
MAX1658/MAX1659 features a special lead frame with
a lower thermal resistance and higher allowable power
dissipation than a standard SO-8. The thermal resistance of this package is θJB = 69°C/W, compared with
θJB = 170°C/W for an SO-8.
The IN pins of the MAX1658/MAX1659 package perform the dual function of providing an electrical connection to IN and channeling heat away. Connect all IN
pins to the input voltage using a large pad or power
plane on the surface. Where this is impossible, connect
to a copper plane on an adjacent layer. The pad should
meet the dimensions specified in Figure 4.
Figure 4 assumes the IC is soldered directly to the pad,
has a +125°C maximum junction temperature and a
+25°C ambient air temperature, and has no other heat
sources. Use larger pad sizes for lower junction temperatures, higher ambient temperatures, or conditions
where the IC is not soldered directly to a heat-sinking
IN pad.
The MAX1658/MAX1659 can regulate currents up to
350mA and operate with input voltages up to 16.5V, but
not simultaneously. High output currents can only be
sustained when input-output differential voltage is low,
8
1600
1400
POWER DISSIPATION (mW)
MAX1658/MAX1659
350mA, 16.5V Input,
Low-Dropout Linear Regulators
Tj = +125°C
1200
1000
Tj = +85°C
800
600
SINGLE-SIDED 1oz. COPPER
TA = +25°C, STILL AIR
400
0.1
0.65
10 (in2)
65 (cm2)
1
6.5
COPPER GROUND PAD AREA
Figure 4. Typical Maximum Power Dissipation vs. Ground Pad
Area
as shown in the following equation. Maximum power
dissipation depends on packaging, board layout, temperature, and air flow. The maximum output current is:
IOUT(MAX) =
(
)
PMAX x 125°C − TA
VIN − VOUT x 100°C
(
)
where PMAX is derived from the TJ = 125°C curve of
Figure 4.
Reverse Battery Protection
The MAX1658/MAX1659 feature reverse battery protection. Under normal operation, a P-channel MOSFET
connects the substrate of the device to IN. When the
input voltage falls below ground (implying reverse battery conditions), the P-channel switch turns off and disconnects the substrate from IN, disabling the device.
The maximum reverse battery voltage allowed is -17V.
SHDN also withstands reverse battery conditions and
can be connected directly to IN with no loss of protection.
Polarized input bypass capacitors will be damaged
under reverse battery conditions. To ensure circuit reliability, use a non-polarized capacitor at the input.
The MAX1658/MAX1659 do not provide reverse current
protection. If VOUT is greater than VIN by more than
300mV, reverse current will flow. Reverse current protection can be added by connecting a Schottky diode
in series with IN.
_______________________________________________________________________________________
350mA, 16.5V Input,
Low-Dropout Linear Regulators
Output Capacitor Selection and Stability
To maintain stability, connect a ≥10µF capacitor with
less than 200mΩ equivalent series resistance (ESR)
from OUT to GND. Larger output capacitors improve
load-transient response. Currents lower than 350mA
make the use of smaller output capacitors possible.
Table 1 shows the maximum output current typically
achieved using various output capacitors. Output voltages higher than 3.3V require less output capacitance
to remain stable.
Table 1. Typical Load Current Capabilities
OUTPUT CAPACITOR
LOAD CURRENT RANGE
2.2µF tantalum
0mA to 120mA
4.7µF tantalum
0mA to 250mA
10µF tantalum
0mA to 350mA
Input Bypass Capacitor
The use of a 0.1µF to 10µF input bypass capacitor is
recommended. Larger capacitors provide better supply-noise rejection and line-transient response, as well
as improved performance when the supply has a high
AC impedance. Polarized input bypass capacitors will
be damaged under reverse battery conditions. If
reverse input voltages are expected, use a non-polarized capacitor at the input.
Noise and PSRR
The MAX1658/MAX1659 exhibit 2.5mVp-p of noise during normal operation. This noise level is negligible in
most applications.
The MAX1658/MAX1659 are designed to maintain
excellent power-supply rejection (55dB) at 50Hz/60Hz
(or 50dB at 120Hz). These regulators are ideal for wallcube applications that may contain significant ripple.
Larger input and output capacitors will further improve
the circuit’s AC response. See the Power-Supply
Rejection Ratio vs. Frequency graphs in the Typical
Operating Characteristics.
___________________Chip Information
TRANSISTOR COUNT: 207
_______________________________________________________________________________________
9
MAX1658/MAX1659
__________Applications Information
________________________________________________________Package Information
SOICN.EPS
MAX1658/MAX1659
350mA, 16.5V Input,
Low-Dropout Linear Regulators
10
______________________________________________________________________________________
350mA, 16.5V Input,
Low-Dropout Linear Regulators
______________________________________________________________________________________
MAX1658/MAX1659
NOTES
11
MAX1658/MAX1659
350mA, 16.5V Input,
Low-Dropout Linear Regulators
NOTES
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.
12 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 1997 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.