SEMTECH SC613IMLTRT

SC613
Low Noise Regulated Charge
Pump with Selectable Output
POWER MANAGEMENT
Description
Features
The SC613 is a versatile charge pump designed for use in battery
operated power supply applications. The wide input range is
matched for Li-Ion battery applications. Only two 1uF ceramic
bucket capacitors are required, and the inductorless implementation provides a reduced-EMI solution. Low noise mode switching
circuitry and constant output current allow the use of 1uF input
and output capacitors.
Small size - MLP Micro 10 lead 3x3mm package
Selectable 5.0V or 4.5V output voltage
140mA available with 4.5V output
100mA available with 5.0V output
Short circuit protection
Soft Start function
Shutdown current <2µA
Selectable fixed frequencies of 262kHz and 650kHz
Low ripple
Regulated to +/-5%
Ease of use
The SC613 charge pump regulator can be used for applications
that require up to 140mA of output current with a 4.5V output.
The 5.0V output version provides up to 100mA of output current.
The small package size, low component count and lower overall
system cost coupled with its low noise make the SC613 a superior solution compared to switch mode regulator designs.
Applications
Cellular phones
LED photo flash for cellular phones
LED backlighting
PDA power supplies
Portable electronics
Electronic books
Wireless web appliances
Typical Application Circuit
U1
Cin
1.0uF
6
4
VIN
EN
VOUT
SC613
3
2.7V to 6.5V
CF1+
CF1-
FSEL
CF2+
5
VSEL
CF2-
1
4.5V or 5.0V
2
9
Cbucket1
1.0uF
Cout
1.0uF
UP TO 10 LEDS
10
7
Cbucket2
1.0uF
GND
8
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SC613
POWER MANAGEMENT
Absolute Maximum Ratings
Parameter
Symbol
Maximum
Units
Supply Voltage
VIN
-0.3 to +7.0
V
Output Voltage
VOUT
-0.3 to +7.0
V
VOUT Short Circuit Duration
SC
Indefinite
Thermal Resistance, Junction To Ambient
(JESD51 Standard Method)
θJ A
31
°C/W
Operating Ambient
TA
-40 to +85
°C
Junction Temperature Range
TJC
-40 to +150
°C
Storage Temperature Range
TSTG
-65 to +150
°C
IR Reflow Temperature
TLEAD
260
°C
Electrical Characteristics
Unless specified: TA = -40°C to 85°C, Cin=Cbucket = 1.0µF (ESR = 0.1Ω), Cout=1.0uF (ESR = 0.1Ω), Vin= 3.2V to 5.5V
Parameter
Symbol
Input Supply Voltage
VIN
Quiescent Current
IQ
Conditions
Min
Typ
2.5
Maximum Output Current
Pump Frequency
VOUT
IOUT
fPUMP
V
1.4
mA
Freq. =650kHz, IOUT = 0mA, VIN =
3.7V
2.1
2.8
mA
2
µA
Static Load Regulation with
VSEL = 1
0mA < IOUT < 100mA
4.75
5.0
5.25
V
Static Load Regulation with
VSEL = 0
0mA < IOUT < 140mA
4.275
4.5
4.725
V
VSEL = 1
100
mA
VSEL = 0
140
mA
Enable = 1, FSEL= 0
-15%
262
+15%
kHz
Enable = 1, FSEL = 1
-20%
650
+20%
kHz
Transition time from one frequency
mode to any other frequency mode
guaranteed by design
Short Circuit Current
ISC
VOUT=0V, IOUT= IIN
Input High Threshold
VIH
All input pins (Enable, VSEL, FSEL)
Input Low Threshold
VIL
All input pins (Enable, VSEL, FSEL)
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6.5
1.0
TLOCK
Frequency Mode Transition Time
Units
Freq. = 262kHz, IOUT = 0mA, VIN =
3.7V
Enable = 0
Output Voltage
Max
2
1
Period
600
1.3
mA
V
0.4
V
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SC613
POWER MANAGEMENT
Electrical Characteristics
Unless specified: TA = -40°C to 85°C, Cin=Cbucket = 1.0µF (ESR = 0.1Ω), Cout=1.0uF (ESR = 0.1Ω), Vin= 3.2V to 5.5V
Parameter
Symbol
Conditions
Input High Current
IIH
Input Low Current
IIL
Power Efficiency from Battery to
Regulated Charge Pump Output
Output Ripple Voltage
h
V PP
Min
Typ
Max
Units
All input pins (Enable, VSEL, FSEL)
10
µA
All input pins (Enable, VSEL, FSEL)
10
µA
VIN = 3.0V, VOUT = 5.0V, IOUT = 50mA
Freq.=262kHz
82.5
%
VIN = 3.0V, VOUT = 5.0V, IOUT = 50mA
Freq.=650kHz
81.5
%
freq = 262kHz, IOUT = 60mA
(1), (2)
25
45
mV
Note:
(1) Peak to peak output ripple voltage with COUT=CBUCKET=1uF and X5R dielectric.
(2) Guaranteed by design.
(3) This device is ESD sensitive. Use of standard ESD handling precautions is required.
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SC613
POWER MANAGEMENT
Pin Configuration
VOUT
1
CF1+
2
VIN
3
FSEL
4
VSEL
5
TOP VIEW
T
Ordering Information
Device
Package (1)
10
CF2+
SC613IMLTRT (2)
MLP-10 3x3mm
9
CF1-
S C 613E V B
Evaluation Board
8
GND
7
CF2-
6
EN
Note:
(1) Available in tape and reel only. A reel contains 3000 devices.
(2) Available in lead-free package only. This product is fully WEEE and
RoHS compliant.
MLP-10 3X3 LEAD
Pin Descriptions
Pin
Pin Name
1
VOUT
Output voltage regulated to 5.0V or 4.5V.
2
C F 1+
Positive terminal of bucket capacitor 1.
3
VIN
Input voltage ranging from 2.5V to 6.5V.
4
FS E L
Logic input for selecting the operational frequency. FSEL= 0, freq = 262kHz;
FSEL= 1, freq = 650kHz.
5
VSEL
Logic input for selecting the output voltage. VSEL = 1, VOUT = 5V; VSEL = 0, VOUT = 4.5V.
6
EN
7
C F 2-
Negative terminal of bucket capacitor 2.
8
GND
Ground.
9
C F 1-
Negative terminal of bucket capacitor 1.
10
C F 2+
Positive terminal of bucket capacitor 2.
T
Thermal Pad
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Pin Function
Active-high enable. Bias current is less than 2uA when set low.
Pad for heat sinking purposes - not connected internally. Connect to ground plane using multiple
vias.
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SC613
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Block Diagram
VIN
3
EN
6
FSEL
4
5
SWITCH
BLOCK
650kHz or 262kHz
EN
VSEL
GND
VOUT
2
CF1+
9
CF1-
10
CF2+
7
CF2-
MODE
SELECT
OSC
COMPARATORS
VIN
VOUT
VREF
1
DRIVERS
54
TIMER
8
VIN
5.0V or 4.5V
difficult to ensure acceptable noise performance over the entire
operating range.
Applications Information
Charge Pump Doubler Type
The SC613 uses a voltage doubler circuit which is implemented
with two switched or ‘bucket’ capactors. Most charge pump doublers use only one bucket capacitor. Two bucket capacitors switching on alternate phases greatly reduce the output ripple voltage
and also reduce the size requirement for the output capacitor.
Many switch mode regulators have increased voltage ripple on
the output during pulse skipping mode due to the fact that there
are large periods of time when no current is supplied to the output.
The SC613 supplies current to the output continuously, so the
voltage ripple is less than a switch mode regulator, even with greatly
reduced output capacitance.
Over Voltage Protection
The output is prevented from exceeding 6.0V. This feature allows
the use of 6.3V ceramic capacitors.
Frequency Selection
The FSEL input is for frequency selection. A logic High level at this
input will set the clock frequency to 650kHz, while a logic Low sets
the clock to 262kHz. Input from a uP or other device may be used
to change the charge pump frequency at any time. The optimal
frequency will depend upon the capacitor values, the load current,
and the exceptable amount of output ripple.
Comparison with Other Regulation Methods
In many instances, a charge pump regulator is the best choice for
portable power applications. These regulators offer many advantages over switch mode regulators. A smaller bill of materials,
less layout area, lower component height, less noise, no EMF, and
less overall circuit cost are typical reasons to use this type of
regulation. The efficiency of a charge pump regulator often approaches and in some cases exceeds the efficiency of a switch
mode regulator.
Ripple Performance
Examples of the output ripple per charge pump frequency and
output voltage are listed in the Ripple Performance table on page
5.
Inductors are often the largest and most expensive discrete component in a design. There are no inductors used in the SC613, so
the inductor’s cost and layout area are eliminated. The noise and
EMF associated with the inductor are also eliminated.
Efficiency
Efficiency for the SC613 is defined as,
η =
The SC613’s fixed frequency harmonics are an advantage in portable communications equipment, such as cellular telephones.
The SC613 has distinct frequencies of operation, so the harmonics are predictable. The harmonics are not fixed in a switch mode
regulator. Switch mode regulators have harmonics which vary
due to the pulse width modulation used to regulate the output.
Varying harmonics can be a problem because it may be more
 2005 Semtech Corp.
where
5
V O⋅ I O
V IN⋅ ( 2⋅ I O + I Q )
VO = output voltage
IO = output current
VIN = input voltage
IQ = quiescent current [from Electrical Characteristics
on page 2].
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SC613
POWER MANAGEMENT
Applications Information (cont.)
Table 2 -Ripple Performance
TA = 25°C, Cin=Cout=Cbucket = 1.0µF (ESR = 0.1Ω)
Freq.
[kHz ]
VOUT
5.0V
4.5V
Ouput Ripple
[mVp-p]
at 100mA and
Vin= 3.2V to 5.5V
262
25
650
15
262
25
650
15
Calculating Power Dissipation
The power dissipated by the SC613 is calculated as,
P D
=
P IN − P OUT
PD
=
V IN ⋅ 2⋅ I O + I Q − V O ⋅ I O
(
)
Short Circuit and Over Temperature Protection
The output is current limited to 600mA to protect against short
circuit conditions. Over temperature protection is also provided.
Design and Layout Considerations
The center pad “thermal slug” is not internally connected to ground,
but should be connected to ground in the layout through vias connecting to the ground plane. Pin 8 can be routed directly to the
center pad. A good ground plane connection is important to make
effective use of the low thermal resistance of the MLP package.
Short Circuit and Over Temperature Protection
The output is current limited to 600mA to protect against short
circuit conditions. Over temperature protection is also provided.
Design and Layout Considerations
The center pad “thermal slug” is not internally connected to ground,
but should be connected to ground in the layout through vias connecting to the ground plane. Pin 8 can be routed directly to the
center pad. A good ground plane connection is important to make
effective use of the low thermal resistance of the MLP package.
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SC613
POWER MANAGEMENT
Typical Characteristics
Efficiency vs. Load Current
Line Regulation for 4.5V
Efficiency vs. Load
80.0%
4.55
4.5
70.0%
4.45
Output Voltage [V]
60.0%
Efficiency [%]
50.0%
5V Output, 3.8V Input
5V Output, 3.2V Input
40.0%
4.5V Output, 3.8V Input
4.5V Output, 3.2V Input
30.0%
4.4
650kHz, 140mA
4.35
4.3
4.25
4.2
650kHz, 75mA
20.0%
4.15
10.0%
4.1
4.05
0.0%
0.0
20.0
40.0
60.0
80.0
100.0
120.0
140.0
2.5
Load Current [mA]
3
3.5
4
4.5
5
5.5
Input Voltage [V]
Load Regulation
Line Regulation for 5.0V
Load Regulation
5.1
5.000
5
4.900
4.800
650kHz, 100mA
Output Voltage [V]
Output Voltage [V]
4.9
4.700
5V Output, 3.8V Input
4.5V Output, 3.8V Input
5V Output, 3.2V Input
4.600
4.5V Output, 3.2V Input
4.500
4.8
4.7
650kHz, 40mA
4.400
4.6
4.300
0.0
20.0
40.0
60.0
80.0
100.0
120.0
140.0
Load Current [mA]
4.5
2.5
3
3.5
4
4.5
5
5.5
Input Voltage [V]
Quiescent Current
Quiescent Currrent
2.500
2.300
2.100
Quiescent Current [mA]
1.900
1.700
Vo=4.5, 262kHz
Vo=5.0V, 262kHz
1.500
Vo=4.5V, 650kHz
Vo=5.0V, 650kHz
1.300
1.100
0.900
0.700
0.500
2.700
3.200
3.700
4.200
4.700
5.200
Input Voltage [V]
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SC613
POWER MANAGEMENT
Start Up for 5.0V, 100mA
Start Up for 4.5V, 100mA
Recommended Minimum Low Pulse Width
Recommended Minimum High Pulse Width
Recommended Maximum 500Hz PWM
Recommended Minimum 100Hz PWM
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SC613
POWER MANAGEMENT
Output Ripple on 5.0V Output at 262kHz
Output Ripple on 5.0V Output at 650kHz
Output Ripple on 4.5V Output at 262kHz
Output Ripple on 4.5V Output at 650kHz
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SC613
POWER MANAGEMENT
Application Schematic
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SC613
POWER MANAGEMENT
Evaluation Board Bill of Materials
Reference
U1
C1, C2, C3, C4
C5
R1 through R10
D1 through D10
Value
SC613
1.0uF
10uF
-
Comment
MLP -Micro 10 lead 3x3mm.
Ceramic, low ESR type, voltage of 6.3V rating is acceptable for all capacitors.
This extra capacitor supports usage of long power leads from a benchtop supply.
Add limiting resistors to meet the requirements of the application on 0805 pads.
Add white or blue LEDs to meet the requirements of the application on 1206 pads.
Marking Information
Top Marking
yyww = Datecode (Example: 0252)
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SC613
POWER MANAGEMENT
Evaluation Board Gerber Plots
Top View
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Bottom View
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SC613
POWER MANAGEMENT
Land Pattern - MLP 3x3-10
A
E
DIMENSIONS
INCHES
MILLIMETERS
DIM
MIN NOM MAX MIN NOM MAX
B
A
A1
A2
b
C
D
E
e
L
N
aaa
bbb
E
PIN 1
INDICATOR
(LASER MARK)
A
aaa C
A1
C
1
.039
.031
.000
.002
(.008)
.007 .009 .011
.074 .079 .083
.042 .048 .052
.114 .118 .122
.020 BSC
.012 .016 .020
10
.003
.004
0.80
1.00
0.00
0.05
(0.20)
0.18 0.23 0.30
1.87 2.02 2.12
1.06 1.21 1.31
2.90 3.00 3.10
0.50 BSC
0.30 0.40 0.50
10
0.08
0.10
SEATING
PLANE
C
A2
2
LxN
D
N
e
bxN
bbb
C A B
NOTES:
1. CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES).
2. COPLANARITY APPLIES TO THE EXPOSED PAD AS WELL AS TERMINALS.
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SC613
POWER MANAGEMENT
Outline Drawing - MLP 3x3-10
K
DIM
H
(C)
G
DIMENSIONS
INCHES
MILLIMETERS
C
G
H
K
P
X
Y
Z
Z
Y
X
(.112)
.075
.055
.087
.020
.012
.037
.150
(2.85)
1.90
1.40
2.20
0.50
0.30
0.95
3.80
P
NOTES:
Land Pattern- MLP-Micro 10
1.
THIS LAND PATTERN IS FOR REFERENCE PURPOSES ONLY.
CONSULT YOUR MANUFACTURING GROUP TO ENSURE YOUR
COMPANY'S MANUFACTURING GUIDELINES ARE MET.
Contact Information
Contact Information
Semtech Corporation
Power Management Products Division
200 Flynn Road, Camarillo, CA 93012
Phone: (805) 498-2111 FAX (805)498-3804
Visit us at: www.semtech.com
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