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19-3894; Rev 4; 9/08
+5V/Programmable Low-Dropout
Voltage Regulator
_______________General Description
The MAX667 low-dropout, positive, linear voltage regu-
lator supplies up to 250mA of output current. With no
load, it has a typical quiescent current of 20µA. At
200mA of output current, the input/output voltage differ-
ential is typically 150mV. Other features include a low-
voltage detector to indicate power failure, as well as
early-warning and low-dropout detectors to indicate an
imminent loss of output voltage regulation. A shutdown
control disables the output and puts the circuit into a
low quiescent-current mode.
The MAX667 employs Dual Mode™ operation. One
mode uses internally trimmed feedback resistors to pro-
duce +5V. In the other mode, the output may be varied
from +1.3V to +16V by connecting two external resistors.
The MAX667 is a pin-compatible upgrade to the
MAX666 in most applications where the input voltages
are above +3.5V. Choose the MAX667 when high out-
put currents and/or low dropout voltages are desired,
as well as for improved performance at higher
temperatures.
____________________________Features
♦
350mV Max Dropout at 200mA
♦
250mA Output Current
♦
Normal Mode: 20µA Typ Quiescent Current
Shutdown Mode: 0.2µA Typ Quiescent Current
♦
Low-Battery Detector
♦
Fixed +5V (Min Component Count) or
Adjustable Output
♦
+3.5V to +16.5V Input
♦
Dropout Detector Output
♦
10µF Output Capacitor
MAX667
Ordering Information
PART
MAX667CPA
MAX667CSA
MAX667C/D
MAX667EPA
MAX667ESA
MAX667MJA
MAX667MSA/PR
TEMP RANGE
0°C to +70°C
0°C to +70°C
0°C to +70°C
-40°C to +85°C
-40°C to +85°C
-55°C to +125°C
-55°C to +125°C
PIN-PACKAGE
8 Plastic DIP
8 SO
Dice*
8 Plastic DIP
8 SO
8 CERDIP**
8 SO†
________________________Applications
Battery-Powered Devices
Pagers and Radio Control Receivers
Portable Instruments
Solar-Powered Instruments
MAX667MSA/PR-T
-55°C to +125°C
8 SO†
*Contact
factory for dice specifications.
**Contact
factory for availability and processing to MIL-STD-883.
†Contact
factory for availability.
__________Typical Operating Circuit
__________________Pin Configuration
TOP VIEW
IN
+6.3V
BATTERY
OUT
C1
10μF
+5V OUT
MAX667
DD
1
OUT
2
LBI
3
GND
4
8
IN
LBO
SET
SHDN
MAX667
7
6
5
SET
GND
SHDN
DIP/SO
TM
Dual
Mode is a trademark of Maxim Integrated Products.
________________________________________________________________
Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
+5V/Programmable Low-Dropout
Voltage Regulator
MAX667
ABSOLUTE MAXIMUM RATINGS
Input Supply Voltage ...........................................................+18V
Output Short Circuited to Ground.........................................1sec
LBO Output Sink Current ....................................................50mA
LBO Output Voltage ...............................................GND to V
OUT
SHDN Input Voltage ....................................-0.3V to (V
IN
+ 0.3V)
Input Voltages LBI, SET................................-0.3V to (V
IN
- 1.0V)
Continuous Power Dissipation
Plastic DIP (derate 9.09mW/°C above +70°C) ............727mW
SO (derate 5.88mW/°C above +70°C) .........................471mW
CERDIP (derate 8.00mW/°C above +70°C) .................640mW
Operating Temperature Ranges
MAX667C_A........................................................0°C to +70°C
MAX667E_A .....................................................-40°C to +85°C
MAX667MJA ..................................................-55°C to +125°C
Storage Temperature Range .............................-65°C to +160°C
Lead Temperature (soldering, 10sec) .............................+300°C
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
(GND = 0V, V
IN
= +9V, V
OUT
= +5V, C1 = 10µF, unless otherwise noted.)
PARAMETER
Input Voltage
SYMBOL
V
IN
V
SET
= 0V, V
IN
= 6V, I
OUT
= 10mA,
T
A
= -40°C to +85°C
V
SET
= 0V, V
IN
= 6V, I
OUT
= 10mA,
T
A
= -55°C to +125°C
V
IN
= 6V, 4.5V < V
OUT
< 5.5V
V
SHDN
= 2V
Quiescent Current
I
Q
V
SHDN
= 0V,
V
SET
= 0V
I
OUT
= 0µA
I
OUT
= 100µA
I
OUT
= 200mA
250
0.2
20
20
5
5
150
50
5
1.225
V
SET
= 1.5V
V
SHDN
= 2V
(Note 2)
1.225
V
LBI
= 1.5V
V
IN
= 9V, V
LBI
= 2V, I
LBO
= 10mA
V
IH
V
IL
V
SHDN
= 0V to V
IN
V
SET
= 0V,
V
SHDN
= 0V,
R
DD
= 100kΩ,
I
OUT
= 10mA
V
IN
= 7V
V
IN
= 4.5V
3.5
1.5
0.3
0.01
±10
0.01
±10
0.25
1.5
0.3
±1000
0.25
V
0.01
0.1
400
1.195
±10
1
25
30
15
60
250
100
10
1.20
5
5
CONDITIONS
T
A
= +25°C
T
A
= T
MIN
to T
MAX
MIN
TYP
MAX MIN
TYP MAX
3.5
4.8
4.75
250
2
35
50
20
75
350
250
15
1.25
±1000
1
450
1.255
±1000
0.4
mA
mV
mV
mV
V
nA
µA
mA
V
nA
V
V
nA
µA
16.5
5.2
V
5.25
mA
UNITS
V
Output Voltage
V
OUT
Maximum Output Current
I
OUT
Dropout Voltage (Note1)
Load Regulation
Line Regulation
SET Reference Voltage
SET Input Leakage Current
Output Leakage Current
Short-Circuit Current
Low-Battery Detector
Reference Voltage
Low-Battery Detector
Input Leakage Current
Low-Battery Detector
Output Voltage
SHDN Threshold
SHDN Leakage Current
V
SET
I
SET
I
OUT
I
OUT
V
LBI
I
LBI
V
LBO
V
SHDN
I
SHDN
I
OUT
= 100µA
I
OUT
= 200mA
I
OUT
= 10mA to 200mA
V
IN
= 6V to 10V, I
OUT
= 10mA
Dropout Detector Output
Voltage
V
DD
Note 1:
Dropout Voltage is V
IN
-V
OUT
when V
OUT
falls to 0.1V below its value at V
IN
= V
OUT
+ 2V.
Note 2:
Short-Circuit Current is pulse tested to maintain junction temperature. Short-circuit duration is limited by package dissipation.
2
_______________________________________________________________________________________
+5V/Programmable Low-Dropout
Voltage Regulator
MAX667
__________________________________________Typical Operating Characteristics
(T
A
= +25°C, unless otherwise noted.)
DROPOUT VOLTAGE
vs. LOAD CURRENT
MAX667-Fg TOC 1
QUIESCENT CURRENT
vs. LOAD CURRENT
MAX667-Fg TOC 2
DD OUTPUT CURRENT
vs. INPUT-OUTPUT DIFFERENCE
5 10
DD OUTPUT CURRENT (μA)
MAX667-Fg TOC 3
1000
100,000
QUIESCENT CURRENT (μA)
VIN = +6V
1000
20 50 100mA LOAD
100
DROPOUT VOLTAGE (mV)
10,000
100
1000
10
10
100
1
1
1
10
100
1000
LOAD CURRENT (mA)
10
0.01
1
0.1
1
10
100
1000
0
LOAD CURRENT (mA)
2
50
100
150
200
250
INPUT-OUTPUT DIFFERENCE (mV)
_____________________Pin Description
PIN
NAME
FUNCTION
Dropout Detector Output—the collec-
tor of a PNP pass transistor. Normally
an open circuit, it sources current as
dropout is reached.
Regulated Output Voltage. OUT falls
to 0V when SHDN is above 1.5V. SET
determines output voltage when SET
is above 50mV; otherwise, it is 5V.
OUT must be connected to an output
filter capacitor.
Low-Battery Detector. A CMOS input
to an internal 1.255V comparator
whose output is the LBO pin.
Ground
Shutdown Input. Connect to GND for
normal operation (output active). Pull
above 1.5V to disable OUT, LBO, and
DD and to reduce quiescent current to
less than 1µA.
(Output) Voltage Set, CMOS Input.
Connect to GND for 5V output. For
other voltages, connect external resis-
tive divider from OUT.
Low-Battery Output. An open-drain N-
channel transistor that sinks current to
GND when LBI is less than 1.22V.
Positive Input Voltage (unregulated)
_______________Detailed Description
Figure 1 shows a micropower bandgap reference, an
error amplifier, a PNP pass transistor, and two com-
parators as the main elements of the MAX667. One
comparator, C1, selects the fixed 5V or adjustable
operation with an external voltage divider. The other
comparator, C2, is a low-battery detector.
The bandgap reference, which is trimmed to 1.22V,
connects internally to one input of the error amplifier,
A1. The feedback signal from the regulator output sup-
plies the other input of A1 from either an on-chip volt-
age divider or two external resistors. When SET is
grounded, the internal divider provides the error ampli-
fier feedback signal for a fixed 5V output. When SET is
more than 50mV above ground, the error amplifier’s
input switches directly to SET while an external resistor
divider from OUT determines the output voltage.
A second comparator, C2, compares the LBI input to
the internal reference voltage. LBO is an open-drain
FET connected to GND. The low-battery threshold can
also be set with a voltage divider at LBI. In addition, the
MAX667 has a shutdown input (SHDN) that disables
the load and the device while reducing quiescent cur-
rent when it is pulled high.
1
DD
2
OUT
3
4
LBI
GND
5
SHDN
6
SET
+5V Output
Figure 2 shows the connection for a fixed 5V output.
The SET input is grounded, and no external resistors
are required. Figure 3 shows adjustable output opera-
tion. R1 and R2 set the output voltage. SHDN should be
grounded if not used.
3
7
8
LBO
IN
_______________________________________________________________________________________
+5V/Programmable Low-Dropout
Voltage Regulator
MAX667
IN
OUT
DD
SHDN
A1
SET
LBO
C2
C1
1.255V REF
LBI
GND
+50mV
MAX667
Figure 1. MAX667 Block Diagram
8
IN
OUT
2
C1
10μF
+5V OUT
250mA
8
MAX667
IN
OUT
2
VOUT
C1
10μF
7 LBO
VREF
R2
3 LBI
6
MAX667
R3
N
SET
SET
6
GND
4
SHDN
5
R4
SHDN
5
GND
4
R1
Figure 2. Fixed +5V Regulator
Figure 3. Adjustable Output and Low-Battery Detector
4
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