19-0227; Rev 2; 5/96
EVALUATION KIT MANUAL
FOLLOWS DATA SHEET
Regulated 5V Charge-Pump
_______________General Description
The MAX619 step-up charge-pump DC-DC converter
delivers a regulated 5V ±4% output at 50mA over temperature. The input voltage range is 2V to 3.6V (two
battery cells).
The complete MAX619 circuit fits into less than 0.1in2of
board space because it requires only four external
capacitors: two 0.22µF flying capacitors, and 10µF
capacitors at the input and output.
Low operating supply current (150µA max) and low
shutdown supply current (1µA max) make this device
ideal for small, portable, and battery-powered applications. When shut down, the load is disconnected from
the input.
The MAX619 is available in 8-pin DIP and SO packages.
________________________Applications
Two Battery Cells to 5V Conversion
Local 3V-to-5V Conversion
Portable Instruments & Handy-Terminals
Battery-Powered Microprocessor-Based Systems
5V Flash Memory Programmer
Minimum Component DC-DC Converters
Remote Data-Acquisition Systems
Compact 5V Op-Amp Supply
Regulated 5V Supply from Lithium Backup Battery
Switching Drive Voltage for MOSFETs in
Low-Voltage Systems
__________________Pin Configuration
DC-DC Converter
____________________________Features
♦ Regulated 5V ±4% Charge Pump
♦ Output Current Guaranteed over Temperature
20mA (VIN≥ 2V)
50mA (V
♦ 2V to 3.6V Input Range
♦ No Inductors; Very Low EMI Noise
♦ Ultra-Small Application Circuit (0.1in
♦ Uses Small, Inexpensive Capacitors
♦ 500kHz Internal Oscillator
♦ Logic-Controlled 1µA Max Shutdown
Supply Current
♦ Shutdown Disconnects Load from Input
♦ 8-Pin DIP and SO Packages
_______________Ordering Information
PART TEMP. RANGE PIN-PACKAGE
MAX619CPA 0°C to +70°C 8 Plastic DIP
MAX619CSA 0°C to +70°C 8 SO
MAX619C/D 0°C to +70°C Dice*
MAX619EPA -40°C to +85°C 8 Plastic DIP
MAX619ESA -40°C to +85°C 8 SO
MAX619MJA -55°C to +125°C 8 CERDIP
* Dice are specified at TA = +25°C.
__________Typical Operating Circuit
IN
≥ 3V)
2
)
MAX619
TOP VIEW
INPUT
2V to 3.6V
10µF
C1+
1
IN
2
OUT
C2+
MAX619
3
4
DIP/SO
________________________________________________________________
C1-
8
SHDN
7
GND
6
C2-
5
ON/OFF
0.22µF
IN
SHDN
C1+
C1-
OUT
MAX619
C2+
C2-
GND
Maxim Integrated Products
10µF
0.22µF
OUTPUT
5V, 20mA
1
For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800
Regulated 5V Charge-Pump
DC-DC Converter
ABSOLUTE MAXIMUM RATINGS
VINto GND ............................................................-0.3V to +5.5V
to GND.........................................................-0.3V to +5.5V
V
OUT
SHDN to GND..............................................-0.3V to (V
Continuous (Note 1)..................................................120mA
I
OUT
Continuous Power Dissipation (T
Plastic DIP (derate 9.09mW/°C above +70°C) ............727mW
SO (derate 5.88mW/°C above +70°C).........................471mW
MAX619
CERDIP (derate 8.00mW/°C above +70°C).................640mW
= +70°C)
A
IN
+ 0.3V)
Note 1: The MAX619 is not short-circuit protected.
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= 2V to 3.6V, C1 = C2 = 0.22µF, C3 = C4 = 10µF, TA= T
PARAMETER SYMBOL MIN TYP MAX UNITS
Input Voltage V
Output Voltage V
Output Ripple V
No-Load Supply Current 75 170
Shutdown Supply
Current
Efficiency Eff %
Switching Frequency 500 kHz
SHDN Input Threshold
SHDN Input Current I
IN
OUT
RIPPLE
I
IN
V
IH
V
IL
IH
2.0V ≤ VIN≤ 3.6V, 0mA ≤ I
3.0V ≤ VIN≤ 3.6V, 0mA ≤ I
3.0V ≤ VIN≤ 3.6V, 0mA ≤ I
3.0V ≤ VIN≤ 3.6V, 0mA ≤ I
2V ≤ V
≤ 3.6V, I
IN
2V ≤V
IN
V
SHDN
VIN= 3V, I
VIN= 3V, I
VIN= 2V, I
= V
≤
3.6V, I
IN
OUT
OUT
OUT
OUT
OUT
= 20mA
= 30mA
= 20mA
At full load
V
= V
SHDN
IN
Operating Temperature Ranges
MAX619C_ _ .......................................................0°C to +70°C
MAX619E_ _ ....................................................-40°C to +85°C
MAX619MJA..................................................-55°C to +125°C
Storage Temperature Range.............................-65°C to +165°C
Lead Temperature (soldering, 10sec).............................+300°C
to T
MIN
, unless otherwise noted. Typical values are at TA= +25°C.)
MAX
CONDITIONS
2 3.6 V
≤ 20mA
OUT
≤ 50mA, MAX619C
OUT
≤ 45mA, MAX619E
OUT
≤ 40mA, MAX619M
OUT
4.8 5.0 5.2 V
100 mVNo load to full load
= 0mA
= 0mA,
MAX619C/E
MAX619M
0.02 1
82
82
80
0.7 x V
IN
MAX619C/E
MAX619M
10
0.4
±1
±10
µA
µA
V
µA
2 ________________________________________________________________________________________
Regulated 5V Charge-Pump
DC-DC Converter
__________________________________________Typical Operating Characteristics
(TA = +25°C, unless otherwise noted.)
EFFICIENCY vs. OUTPUT CURRENT
90
85
80
75
70
EFFICIENCY (%)
65
60
AND INPUT VOLTAGE
VIN = 2.0V
1 10 100
I
OUT
(mA)
OUTPUT VOLTAGE vs. OUTPUT CURRENT
5.05
5.00
4.95
(V)
4.90
OUT
V
4.85
4.80
4.75
1 10 100
VIN = 1.8V
VIN = 2.0V
VIN = 2.4V, 2.7V
VIN = 3.0V
I
OUT
VIN = 3.3V
(mA)
LOAD-TRANSIENT RESPONSE
VIN = 1.8V
VIN = 3.3V
VIN = 3.6V
VIN = 2.4V
VIN = 2.7V
V
= 3.0V
IN
= 3.6V
VIN = 3.6V
INPUT CURRENT vs. OUTPUT CURRENT
200
180
160
140
120
(mA)
100
IN
I
80
A
60
40
20
0
0
10 20 30 40 50 60 70 80 90 100
D
C
B
(mA)
I
OUT
G
F
E
I
OUT
V
IN
MAX
A
18
1.8
B
36
2.0
41
2.4
C
64
2.7
D
E
72
3.0
F
94
3.6
G
100
3.3
1000
(µA)
IN
I
OUTPUT VOLTAGE vs. INPUT VOLTAGE
5.06
(V)
OUT
V
5.04
5.02
5.00
4.98
4.96
4.94
I
= 20mA
OUT
2.01.5 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0
(V)
V
IN
EFFICIENCY (%)
LINE-TRANSIENT RESPONSE (I
NO-LOAD INPUT CURRENT
vs. INPUT VOLTAGE
SHDN = 0V
100
10
1.0
0.1
0.01
1.5 2.0 2.5 3.0 3.5 4.0 4.5
SHDN = V
(V)
V
IN
IN
EFFICIENCY vs. INPUT VOLTAGE
90
85
80
75
70
65
60
1.5
2.0 2.5 3.0 3.5 4.0
= 20mA)
OUT
I
= 10mA
OUT
V
(V)
IN
MAX619
TOP TRACE: OUTPUT CURRENT, 0mA to 25mA, 10mA/div
BOTTOM TRACE: OUTPUT VOLTAGE, 5mV/div, AC-COUPLED
2ms/div
R
= 250Ω, V
LOAD
TOP TRACE: V
BOTTOM TRACE: OUTPUT VOLTAGE, 50mV/div, AC-COUPLED
2ms/div
= 5V, I
OUT
OUT
= 2V to 3V, 1V/div
IN
= 20mA
________________________________________________________________________________________
3
Regulated 5V Charge-Pump
DC-DC Converter
_____________________Pin Description
FUNCTIONNAMEPIN
Positive Terminal for C1C1+1
Input Supply VoltageIN2
MAX619
+5V Output Voltage. V
OUT3
shutdown mode.
Positive Terminal for C2C2+4
Negative Terminal for C2C2-5
GroundGND6
Active-High CMOS Logic-Level Shutdown InputSHDN7
Negative Terminal for C1C1-8
= 0V when in
OUT
_______________Detailed Description
The MAX619 provides a regulated 5V output from a 2V
to 3.6V (two battery cells) input. Internal charge pumps
and external capacitors generate the 5V output, eliminating the need for inductors. The output voltage is
regulated to 5V ±4% by a pulse-skipping controller that
turns on the charge pump when the output voltage
begins to droop.
To maintain the greatest efficiency over the entire input
voltage range, the MAX619’s internal charge pump
operates as a voltage doubler when VINranges from
3.0V to 3.6V, and as a voltage tripler when VINranges
from 2.0V to 2.5V. When VINranges from 2.5V to 3.0V,
Operating Principle
the MAX619 switches between doubler and tripler
mode on alternating cycles, making a 2.5 x VINcharge
pump. To further enhance efficiency over the input
range, an internal comparator selects the higher of V
or V
Efficiency with VIN= 2V and I
80%.
Figure 1 shows a detailed block diagram of the
MAX619. In tripler mode, when the S1 switches close,
the S2 switches open and capacitors C1 and C2
charge up to VIN. On the second half of the cycle, C1
and C2 are connected in series between IN and OUT
when the S1 switches open and the S2 switches close,
as shown in Figure 1. In doubler mode, only C2 is
used.
During one oscillator cycle, energy is transferred from
the input to the charge-pump capacitors, and then
from the charge-pump capacitors to the output capacitor and load. The number of cycles within a given time
frame increases as the load increases or as the input
supply voltage decreases. In the limiting case, the
charge pumps operate continuously, and the oscillator
frequency is nominally 500kHz.
to run the MAX619’s internal circuitry.
OUT
= 20mA is typically
OUT
Shutdown Mode
The MAX619 enters low-power shutdown mode when
SHDN is a logic high. SHDN is a CMOS-compatible
input. In shutdown mode, the charge-pump switching
action is halted, OUT is disconnected from IN, and
V
falls to 0V. Connect SHDN to ground for normal
OUT
operation. When VIN= 3.6V, V
5V in 0.5ms under no-load conditions after SHDN goes
low.
typically reaches
OUT
IN
4 ________________________________________________________________________________________
C3
10µF
C2
0.22µF
C1
0.22µF
C2+
C1+
Regulated 5V Charge-Pump
DC-DC Converter
MAX619
IN
P
S1A
*
S2A
V
IN/VOUT
IN
C2-
S1B
CONTROL
P
FB
LOGIC
S2B
S1C
C1-
S1D
S2C
SWITCH
CONTROL
BUS
SD
IC
POWER
V
REF
MAX619
OUT
C4
10µF
SHDN
SWITCHES SHOWN IN TRIPLER MODE, DISCHARGE CYCLE
*
Figure 1. Block Diagram
________________________________________________________________________________________ 5
GND
Regulated 5V Charge-Pump
DC-DC Converter
__________Applications Information
Capacitor Selection
The values of charge-pump capacitors C1 and C2 are
critical to ensure adequate output current and avoid
excessive peak currents. Use values in the range of
0.22µF to 1.0µF. Larger capacitors (up to 50µF) can
MAX619
be used, but larger capacitors will increase output ripple. Ceramic or tantalum capacitors are recommended.
The type of input bypass capacitor (C3) and output filter capacitor (C4) used is not critical, but it does affect
performance. Tantalums, ceramics, or aluminum electrolytics are suggested. For smallest size, use Sprague
595D106X0010A2 surface-mount capacitors, which
measure 3.7mm x 1.8mm (0.146in x 0.072in). For lowest ripple, use large, low effective-series-resistance
(ESR) ceramic or tantalum capacitors. For lowest cost,
use aluminum electrolytic or tantalum capacitors.
Figure 2 shows the component values for proper operation using minimal board space. The input bypass
capacitor (C3) and output filter capacitor (C4) should
both be at least 10µF when using aluminum electrolytics or Sprague’s miniature 595D series of tantalum chip
capacitors.
Charge-Pump Capacitors C1 and C2
Input and Output Capacitors, C3 and C4
When using ceramic capacitors, the values of C3 and
C4 can be reduced to 2µF and 1µF, respectively. If the
input supply source impedance is very low, C3 may not
be necessary.
Many capacitors exhibit 40% to 50% variation over
temperature. Compensate for capacitor temperature
coefficient by selecting a larger nominal value to
ensure proper operation over temperature. Table 1 lists
capacitor suppliers.
1
C2
0.22µF
2
CELLS
C3
10µF
Figure 2. Two-Cell to 5V Application Circuit
C1+
MAX619
8
C1–
2
IN
6
GND
C2+
C2–
SHDN
OUT
4
C1
0.22µF
5
7
3
C4
10µF
5V ±4%
@ 20mA
Table 1. Capacitor Suppliers
CAPACITOR TYPE*CAPACITORFAX NUMBERPHONE NUMBERSUPPLIER
GRM42-6Z5U10M50
(814) 238-0490(814) 237-1431Murata Erie
Sprague Electric
(smallest size)
* Note: (SM) denotes surface-mount component, (TH) denotes through-hole component.
6 ________________________________________________________________________________________
(603) 224-1961
(207) 327-4140
(603) 224-1430
(207) 324-7223
GRM42-6Z5U22M50
RPI123Z5U105M50V
RPE121Z5U104M50V
595D106X0010A2
0.1µF ceramic (SM)
0.22µF ceramic (SM)
1.0µF ceramic (TH)
0.1µF ceramic (TH)
10µF tantalum (SM)
Regulated 5V Charge-Pump
DC-DC Converter
Layout Considerations
The MAX619’s high oscillator frequency makes good
layout important. A good layout ensures stability and
helps maintain the output voltage under heavy loads.
For best performance, use very short connections to
the capacitors.
Paralleling Devices
Two MAX619s can be placed in parallel to increase
output drive capability. The IN, OUT, and GND pins
can be paralleled, but C1 and C2 pins cannot. The
input bypass capacitor and output filter capacitor are,
to some extent, shared when two circuits are paralleled. If the circuits are physically close together, it
may be possible to use a single bypass and a single
output capacitor, each with twice the value of the single
circuit. If the MAX619s cannot be placed close together, use separate bypass and output capacitors. The
amount of output ripple observed will determine
whether single input bypass and output filter capacitors
can be used.
MAX619
IN
INPUT
OUT
GND
5V, 40mA
___________________Chip Topography
0.072”
(1.828mm)
C1-
C2-
SHDN
GND
0.115”
(2.921mm)
C1+
IN
OUT
C2+
TRANSISTOR COUNT: 599;
SUBSTRATE CONNECTED TO GND.
MAX619
MAX619
IN
GND
Figure 3. Paralleling Two MAX619s
________________________________________________________________________________________ 7
OUT
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