19-1376; Rev 1; 12/98
3V to 5V Regulating
Charge Pumps for SIM Cards
General Description
The MAX1686 provides power for dual-voltage sub-
scriber ID module (SIM) cards in portable applications
such as GSM cellular phones. Designed to reside in the
portable unit (cellular phone handset), the 1MHz charge
pump converts a 2.7V to 4.2V input to regulated 5V out-
put. The MAX1686H has a nominal output voltage of
5.0V, while the MAX1686 is set to 4.75V to reduce SIM-
card current drain. The charge pump has only 45µA qui-
escent supply current, which reduces to 3µA when a
3V-capable SIM card is being powered and the charge
pump is disabled. An internal input/output shorting
switch provides power for 3V SIM cards.
The MAX1686/MAX1686H require only three external
capacitors around their space-saving, thin (1mm) 8-pin
µMAX packages.
o
2.7V to 4.2V Input Range
o
12mA min Charge-Pump Output Current
o
45µA Quiescent Supply Current
o
0.1µA Supply Current in Shutdown Mode
o
5.0V Regulated Charge-Pump Output (MAX1686H)
4.75V Regulated Charge-Pump Output (MAX1686)
o
Input-Output Shorting Switch for 3V Cards
o
Small External Components
(Uses a 0.047µF, 0.1µF, and a 2.2µF Capacitor)
o
Output Driven to Ground in Shutdown Mode
o
Super-Small 8-Pin µMAX Package
o
Soft-Start and Short-Circuit Protection
Features
MAX1686/MAX1686H
Applications
GSM Cellular Phones
PCS Phones
Portable POS Terminals
Personal Communicators
PART
MAX1686EUA
MAX1686HEUA
Ordering Information
TEMP. RANGE
-40°C to +85°C
-40°C to +85°C
PIN-PACKAGE
8 µMAX
8 µMAX
Typical Operating Circuit
C
X
Pin Configuration
TOP VIEW
INPUT
2.7V TO 4.2V
IN
C
IN
CXN
CXP
OUT
OUTPUT
V
IN
OR 5V/20mA
C
OUT
3/5
SHDN
IN
GND
1
2
3
4
8
OUT
CXP
CXN
PGND
MAX1686
MAX1686H
SHDN
3/5
GND
PGND
MAX1686
MAX1686H
µMAX
7
6
5
________________________________________________________________
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 1-800-835-8769.
3V to 5V Regulating
Charge Pumps for SIM Cards
MAX1686/MAX1686H
ABSOLUTE MAXIMUM RATINGS
IN, OUT,
SHDN,
3/5 to GND.....................................-0.3V to +6V
CXP to GND..............................................-0.3V to (V
OUT
+ 0.3V)
CXN to GND ................................................-0.3V to (V
IN
+ 0.3V)
PGND to GND ......................................................-0.3V to + 0.3V
OUT Short Circuit to GND ..........................................Continuous
IN-to-OUT Current...............................................................50mA
Continuous Power Dissipation (T
A
= +70°C )
8-Pin µMAX (derate 4.1mW/°C above +70°C) .............330mW
Operating Temperature Range
MAX1686EUA/MAX1686HEUA........................-40°C to +85°C
Junction Temperature ......................................................+150°C
Storage Temperature Range .............................-65°C to +165°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
(V
IN
= V
SHDN
= 3.3V, 3/5 = GND, C
X
= 0.22µF, C
OUT
= 10µF (see
Applications Information
section to use smaller capacitors),
T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at T
A
= +25°C.) (Note 1)
PARAMETER
Input Voltage Range
Input Undervoltage-Lockout
Threshold Voltage
Quiescent Supply Current
Shutdown Supply Current
OUT Output Voltage
IN-to-OUT Switch On-Resistance
OUT Discharge Switch On-Resistance
OUT Short-Circuit Current
Logic Input Low Voltage
Logic Input High Voltage
Logic Input Leakage Current
Charge-Pump Frequency
Charge pump enabled,
no load, 3/5 = GND
V
IN
= 3.6V,
SHDN
= GND
V
IN
= 2.7V to 4.2V,
load = 0 to 12mA
3/5 = IN
V
3/5
= V
IN
= 3.0V
3/5 = GND or IN,
SHDN
= GND
3/5 = GND or IN
SHDN,
3/5
SHDN,
3/5
SHDN,
3/5 = GND or IN
T
A
= +25°C
T
A
= -40°C to +85°C
800
700
20
MAX1686
MAX1686H
4.55
4.75
T
A
= +25°C
T
A
= -40°C to +85°C
3
0.1
4.75
5.00
V
IN
2.5
80
100
5
200
200
Ω
Ω
mA
V
V
1
1200
1300
µA
kHz
CONDITIONS
MIN
2.7
0.8
1.2
45
TYP
MAX
4.2
1.6
100
150
10
5
5.25
5.25
V
µA
µA
UNITS
V
V
Charge pump disabled, no load, 3/5 = IN
0.5
·
V
IN
0.3
·
V
IN
0.7
·
V
IN
0.5
·
V
IN
0.1
1000
Note 1:
Electrical specifications are measured by pulse testing and are guaranteed for a junction temperature within the operating
temperature range, unless otherwise noted. Limits are 100% production tested at T
A
= +25°C. Limits over the entire operat-
ing temperature range are guaranteed through correlation using Statistical Quality Control (SQC) methods and are not pro-
duction tested.
2
_______________________________________________________________________________________
3V to 5V Regulating
Charge Pumps for SIM Cards
Typical Operating Characteristics
(See
Typical Operating Circuit,
C
IN
= 0.47µF, C
X
= 0.22µF, C
OUT
= 10µF, V
IN
= 3.3V, T
A
= +25°C, unless otherwise noted.)
EFFICIENCY vs. LOAD CURRENT
(5V MODE)
80
70
EFFICIENCY (%)
60
50
40
30
20
10
0
0.1
1
10
100
LOAD CURRENT (mA)
V
IN
= 3.6V
V
IN
= 2 .7V
MAX1686-01
MAX1686/MAX1686H
EFFICIENCY vs. INPUT VOLTAGE
(5V MODE)
MAX1686-TOC2
NO-LOAD INPUT CURRENT
vs. INPUT VOLTAGE (3V MODE)
MAX1686-03
90
V
IN
= 3.3V
90
80
70
EFFICIENCY (%)
60
50
40
30
20
10
0
0
1
2
3
4
5
I
LOAD
= 1mA
I
LOAD
= 10mA
1000
INPUT CURRENT (µA)
100
10
1
0.1
6
0
1
2
3
4
5
6
INPUT VOLTAGE (V)
INPUT VOLTAGE (V)
NO-LOAD INPUT CURRENT
vs. INPUT VOLTAGE (5V MODE)
MAX1686-04
OUTPUT VOLTAGE
vs. LOAD CURRENT (3V MODE)
MAX1686-05
MAX1686 OUTPUT VOLTAGE
vs. LOAD CURRENT (5V MODE)
4.79
4.78
OUTPUT VOLTAGE (V)
MAX1686-06
10,000
3.34
3.32
OUTPUT VOLTAGE (V)
3.30
3.28
3.26
3.24
3.22
3.20
4.80
INPUT CURRENT (µA)
1000
4.77
4.76
4.75
4.74
4.73
4.72
4.71
4.70
V
IN
= 3.6V
V
IN
= 3 .3V
V
IN
= 2.7V
100
10
1
0
1
2
3
4
5
6
INPUT VOLTAGE (V)
0
5
10
15
20
25
0.1
1
10
100
LOAD CURRENT (mA)
LOAD CURRENT (mA)
OUTPUT VOLTAGE
vs. INPUT VOLTAGE (3V MODE)
MAX1686-07
OUTPUT VOLTAGE
vs. INPUT VOLTAGE (5V MODE)
MAX1686-08
OUTPUT WAVEFORM
(I
LOAD
= 10mA)
MAX1686-09
6
NO LOAD
5
OUTPUT VOLTAGE (V)
4
3
2
1
0
0
1
2
3
4
5
6
INPUT VOLTAGE (V)
6
NO LOAD
5
OUTPUT VOLTAGE (V)
4
3
2
1
0
0
1
2
3
4
5
6
MAX1686
MAX1686H
V
OUT
(20mV/div)
2.5µs/div
5V MODE, AC COUPLED,
C
OUT
= 10µF
0.1µF
INPUT VOLTAGE (V)
_______________________________________________________________________________________
3
3V to 5V Regulating
Charge Pumps for SIM Cards
MAX1686/MAX1686H
Typical Operating Characteristics (continued)
(See
Typical Operating Circuit,
C
IN
= 0.47µF, C
X
= 0.22µF, C
OUT
= 10µF, V
IN
= 3.3V, T
A
= +25°C, unless otherwise noted.)
OUTPUT WAVEFORM
(I
LOAD
= 1mA)
MAX1686-10
LINE-TRANSIENT RESPONSE
MAX1686-11
LOAD-TRANSIENT RESPONSE
MAX1686-12
V
IN
(500mV/div)
I
LOAD
(10mA/div)
V
OUT
(20mV/div)
V
OUT
(50mV/div)
V
OUT
(50mV/div)
25µs/div
5V MODE, AC COUPLED,
C
OUT
= 10µF
0.1µF
2.5ms/div
V
IN
= 2.8V to 3.3V, I
LOAD
= 10mA, 5V MODE,
AC COUPLED
2.5ms/div
I
LOAD
= 0 TO 10mA, 5V MODE, AC COUPLED
START-UP WAVEFORM
(3V MODE, R
L
= 500Ω)
MAX1686-13
START-UP WAVEFORM
(5V MODE, R
L
= 500Ω)
MAX1686-14
3V MODE TO 5V MODE
WAVEFORM (R
L
= 500Ω)
MAX1686-15
SHDN
(5V/div)
SHDN
(5V/div)
3/5
(5V/div)
V
OUT
(1V/div)
V
OUT
(1V/div)
0V
250µs/div
V
OUT
(1V/div)
0V
0V
250µs/div
250µs/div
SHUTDOWN WAVEFORM
(3V MODE, NO LOAD)
MAX1686-16
SHUTDOWN WAVEFORM
(5V MODE, NO LOAD)
MAX1686-17
5V MODE TO 3V MODE
WAVEFORM (NO LOAD)
MAX1686-18
SHDN
(5V/div)
SHDN
(5V/div)
3/5
(5V/div)
V
OUT
(1V/div)
0V
1ms/div
R
L
= 500Ω
V
OUT
(1V/div)
V
OUT
(1V/div)
0V
0V
1ms/div
500µs/div
4
_______________________________________________________________________________________
3V to 5V Regulating
Charge Pumps for SIM Cards
Pin Description
PIN
1
2
3
4
5
6
7
8
NAME
3/5
SHDN
IN
GND
PGND
CXN
CXP
OUT
FUNCTION
3V/5V Select Input. When low, the output is regulated at 4.75V for MAX1686, 5.00V for MAX1686H. When
high, the output is shorted to the input.
Active-Low Shutdown Input.
SHDN
= GND is off. Output is actively pulled low in shutdown.
Supply Input Pin. Can range from 2.7V to 4.2V. Bypass to ground with a ceramic capacitor.
Ground Pin
Power Ground. Connect to GND through a short trace.
Negative Terminal of the Charge-Pump Transfer Capacitor
Positive Terminal of the Charge-Pump Transfer Capacitor
Power Output. Bypass to GND with an output filter capacitor.
C
X
MAX1686/MAX1686H
CXN
IN
CXP
OUT
PGND
S1
S2
OSC
EN
1.23V
PWROK
SHDN
3/5
SS
POWER
MANAGEMENT
DIS
MAX1686
MAX1686H
GND
Figure 1. Functional Diagram
_______________Detailed Description
The MAX1686/MAX1686H charge pumps provide two
modes of operation: 3V mode or 5V mode. The devices
consist of an error amplifier, a 1.23V bandgap refer-
ence, an internal resistive feedback network, a 1MHz
oscillator, high-current MOSFET drivers and switches,
and a power-management block as shown in the
Functional Diagram
(Figure 1). In 3V mode (3/5 = IN),
the input is connected to the output through a 2.5Ω
switch. In 5V mode (3/5 = GND), the MAX1686’s output
voltage is regulated at 4.75V (5.00V for the MAX1686H)
with a 2.7V to 4.2V input and can deliver more than
12mA of load current.
Designed specifically for compact applications, these
regulators require only three small external capacitors.
The Skip Mode control scheme provides high efficiency
over a wide output current range. The devices offer a
shutdown feature which actively discharges the output
to ground and reduces the supply current to less than
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