SEMTECH SC630ULTRT

SC630
Fixed 3.3V High Output
Charge Pump Buck/Boost Regulator
POWER MANAGEMENT
Features
Description
„
The SC630 is a high-current voltage regulator using
Semtech’s proprietary low-noise charge pump technology. Performance is optimized for use in single Li-Ion
battery cell applications. The regulator provides the performance of a linear, low drop-out (LDO) voltage regulator
when the battery is greater than 3.3V. Unlike an LDO,
drop-out is avoided when the battery is less than 3.3V.
Instead, a charge pump is activated to provide voltage
boost — the head-room needed for voltage regulation.
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Input voltage range — 2.9V to 5.5V
VOUT tolerance 3.3V ±3%
VOUT regulation (line + load) ±2%
Continuous output current — 400mA
Peak output current — 500mA
Three charge pump modes — 1x, 1.5x and 2x
Output ripple ≤ 20mVpp for IOUT ≤ 400mA
Short circuit, over-voltage, and over-temperature
protection
Soft-start functionality
Shutdown current — 0.1μA, typical
Ultra thin package — 2 x 2 x 0.6 (mm)
Fully WEEE and RoHS compliant
Applications
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Only two 2.2μF bucket capacitors are required to deliver
the full output current. The charge pump provides a low
EMI solution compared to inductive buck/boost
regulators.
The SC630’s charge pump has three modes of operation:
2x, 1.5x, and 1x modes. The 2x and 1.5x modes deliver
current to the load in each of two phases. The 1x mode
turns off the charge pump, delivering current through an
LDO. When active, the charge pump provides low-ripple
operation at 200kHz, which is typically less than 20mVpp
at the output. The SC630 is capable of delivering 400mA
continuous current, with peak current to 500mA. A 22μF
output capacitor of is used for decoupling the load and for
smoothing mode transitions. Hysteresis is provided to
prevent chatter between charge pump modes.
Mobile phones
MP3 players
Multi-LED backlit LCDs
Compact flash/CF+ products
PMPs
Digital video cameras
Digital still cameras
PDAs
The micro lead-frame package is both small and thermally
efficient, measuring 2 x 2 x 0.6 (mm).
Typical Application Circuit
CIN
22μF
VBAT
IN
OUT
VOUT = 3.3V @ 400mA
COUT
22μF
SC630
Chip
enable
EN
C1+
C1C2+
GND
C2-
C1
2.2μF
C2
2.2μF
Patents Pending
May 28, 2008
© 2008 Semtech Corporation
1
SC630
Pin Configuration
GND
Ordering Information
1
8
C2-
Device
Package
SC630ULTRT(1)(2)
MLPD-UT-8 2x2
SC630EVB
Evaluation Board
Notes:
(1) Available in tape and reel only. A reel contains 3,000 devices.
(2) Lead-free package only. Device is WEEE and RoHS compliant.
TOP VIEW
C1+
2
7
C2+
C1-
3
6
OUT
5
EN
T
IN
4
MLPD-UT-8; 2x2, 8 LEAD
θJA = 68°C/W
Marking Information
630
yw
yw = Datecode
2
SC630
Absolute Maximum Ratings
Recommended Operating Conditions
IN, OUT (V) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3 to +6.0
Ambient Temperature Range (°C) . . . . . . . . -40 < TA < +85
C1+, C2+ (V) . . . . . . . . . . . . . . . . . . . . . . . . . . .-0.3 to (VOUT + 0.3)
IN (V) ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.9 < VIN < 5.5
Pin Voltage - All Other Pins (V) . . . . . . . . . . . -0.3 to (VIN + 0.3)
OUT Short Circuit Duration . . . . . . . . . . . . . . . . . Continuous
ESD Protection Level(1) (kV) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Thermal Information
Thermal Resistance, Junction to Ambient(2) (°C/W) . . . . . 68
Maximum Junction Temperature (°C) . . . . . . . . . . . . . . +150
Storage Temperature Range (°C) . . . . . . . . . . . . -65 to +150
Peak IR Reflow Temperature (10s to 30s) (°C) . . . . . . . +260
Exceeding the above specifications may result in permanent damage to the device or device malfunction. Operation outside of the parameters
specified in the Electrical Characteristics section is not recommended.
NOTES
(1) Tested according to JEDEC standard JESD22-A114-B.
(2) Calculated from package in still air, mounted to 3 x 4.5 (in), 4 layer FR4 PCB with thermal vias under the exposed pad per JESD51 standards.
Electrical Characteristics
Unless otherwise specified: TA = +25°C for Typ, -40°C to +85°C for Min and Max; C1 = C2 = 2.2μF (ESR < 0.03Ω); CIN = COUT = 22μF; VIN = 2.9V to 5.5V
Parameter
Symbol
Condition
Input Supply Voltage
VIN
Output Voltage
VOUT
VIN = 4.2V, IOUT = 1mA
Output Voltage Ripple
VPP
IOUT ≤ 400mA
Maximum Output Current
IOUT
Shutdown Current
ISD
Total Quiescent Current
IQ
Charge Pump Frequency
Min
Typ
2.9
3.2
3.3
Max
Units
5.5
V
3.4
V
20
mV
Peak Load - thermally limited(1),
TJ <150°C, 2.85V ≤ VIN ≤ 5.5V
500
mA
Continuous Load, 3.1V ≤ VIN ≤ 5.5V, 1x or 1.5x mode
400
mA
Shutdown (EN = GND), VIN = 3.6V
0.1
2
μA
EN high, 1x mode, IOUT = 1mA, VIN = 4.2V
1.5
2.0
mA
EN high, 1.5x or 2x mode, IOUT = 1mA, VIN = 3.3V
1.5
2.5
mA
200
260
kHz
fPUMP
VIN = 3.2V
tSU
(EN transitions from low to high),
3.2V ≤ VOUT ≤ 3.4V, No load
Line Regulation
ΔVLINE
IOUT = 1mA, 2.85V ≤ VIN ≤ 4.2V
21
mV
Load Regulation
ΔVLOAD
VIN Fixed, 1mA ≤ IOUT ≤ 500mA
25
mV
Start-Up Time
140
400
μs
3
SC630
Electrical Characteristics (continued)
Parameter
Symbol
Condition
Min
EN Input High Threshold
VIH
VIN = 5.5V
1.6
EN Input Low Threshold
VIL
VIN = 2.7V
0.4
V
EN Input High Current
IIH
VIN = 5.5V
2
μA
EN Input Low Current
IIL
VIN = 5.5V
2
μA
Open-Loop Output Resistance
Typ
Max
Units
V
1x mode
0.3
Ω
1.5x mode, VIN = 3.15V
3
Ω
2x mode, VIN = 2.93V
2.4
Ω
V TRANS 1X
IOUT = 300mA
3.3
V
V TRANS 1.5X
IOUT = 300mA
2.93
V
ISC
VOUT = 0V, IOUT = IIN
300
600
980
mA
1x mode
0.6
1.2
2.0
A
1.5x and 2x modes
1.2
2.0
2.8
A
ROUT
Mode Transition Voltage (2)
Fault Protection
Short-Circuit Current
Input Current Limit
ILIMIT
VOUT ≤ 2V, IOUT = IIN
700
mA
TOTP
Rising Threshold
165
°C
THYS
Hysteresis
20
°C
Over Temperature (3)
Notes:
(1) Thermal limitation is dependent upon the thermal performance of the printed circuit board in support of the package standard of 68° C/W.
(2) Voltage at the IN pin where a mode transition takes place in the charge pump with VIN falling.
(3) Guaranteed by design - not tested in production.
4
SC630
Typical Characteristics
Line Regulation
Load Regulation
VOUT = 3.3V, VIN = 3.6V
20
Output Voltage Variation — ΔVLINE (mV)
Output Voltage Variation — ΔVLOAD (mV)
25
20
TA=85°C
15
TA=25°C
10
TA=-40°C
5
0
0
90
180
270
Output Current (mA)
360
VOUT = 3.3V, IOUT = 1mA
15
85°C
10
5
-40°C
0
-5
-10
-15
-20
2.7
450
0
VIN = 3.4V
3.9
4.3
4.7
5.1
5.5
VIN = 4.2V, VOUT = 3.3V, IOUT = 50mA
CIN=COUT=22μF (0805)
-10
VIN = 3.6V
C1=C2=2.2μF (0603)
-20
VIN = 3.8V
-30
VIN = 4.0V
80
Gain (dB)
Efficiency (%)
3.5
PSRR — 1x Mode
VOUT = 3.3V
90
3.1
Input Voltage (V)
Efficiency versus Load Current
100
25°C
3.6V, 0mV
70
-40
-50
-60
-70
60
-80
50
-100
10
-90
0
90
180
270
360
450
100
1000
10000
Frequency (Hz)
Load Current (mA)
PSRR — 1.5x Mode
VIN = 3.2V, VOUT = 3.3V, IOUT = 50mA
0
CIN=COUT=22μF (0805)
-10
C1=C2=2.2μF (0603)
-20
Gain (dB)
-30
-40
-50
-60
-70
-80
-90
-100
10
100
Frequency (Hz)
1000
10000
5
SC630
Typical Characteristics (continued)
Efficiency — 10mA
100
Efficiency — 50mA
VOUT = 3.3V, IOUT = 10mA
100
90
VOUT = 3.3V, IOUT = 50mA
90
1x Mode
Efficiency(%)
Efficiency(%)
1x Mode
80
Mode
Transition
Hysteresis
70
80
Mode
Transition
Hysteresis
70
1.5x Mode
1.5x Mode
60
60
50
4.2
3.9
3.0
3.6
3.3
Input Voltage (V)
50
4.2
2.7
3.9
Efficiency — 100mA
100
90
2.7
VOUT = 3.3V, IOUT = 200mA
90
1x Mode
Efficiency(%)
3.0
Efficiency — 200mA
VOUT = 3.3V, IOUT = 100mA
100
3.6
3.3
Input Voltage (V)
1x Mode
Efficiency(%)
80
Mode
Transition
Hysteresis
70
80
Mode
Transition
Hysteresis
70
1.5x Mode
1.5x Mode
60
60
50
50
4.2
2x Mode
4.2
3.9
3.6
3.3
Input Voltage (V)
3.0
2.7
Efficiency — 300mA
100
3.6
3.3
Input Voltage (V)
3.9
3.0
2.7
3.0
2.7
Efficiency — 400mA
VOUT = 3.3V, IOUT = 300mA
100
VOUT = 3.3V, IOUT = 400mA
1x Mode
1x Mode
76
88
Mode
Transition
Hysteresis
Efficiency(%)
Efficiency(%)
88
1.5x Mode
64
52
76
1.5x Mode
64
52
Mode
Transition
Hysteresis
2x Mode
2x Mode
40
4.2
3.9
3.6
3.3
Input Voltage (V)
3.0
2.7
40
4.2
3.9
3.6
3.3
Input Voltage (V)
6
SC630
Typical Characteristics (continued)
Ripple — 1.5x Mode
Ripple — 1x Mode
VIN=3.6V, VOUT=3.3V, IOUT=400mA
VIN=3.2V, VOUT=3.3V, IOUT=400mA
VIN -PP (20mV/div)
VIN -PP (100mV/div)
VOUT -PP (20mV/div)
VOUT -PP (50mV/div)
IOUT (200mA/div)
400mA
IOUT (200mA/div)
400mA
CIN=COUT=22μF (0805)
CIN=COUT=22μF (0805)
C1=C2=2.2μF (0603)
0mA
0mA
C1=C2=2.2μF (0603)
Time (10μs/div)
Time (10μs/div)
Startup (No Load)
Ripple — 2x Mode
VIN=2.85V, VOUT=3.3V, IOUT=400mA
VIN=3.6V, IOUT=0mA
VIN -PP (50mV/div)
VEN (2V/div)–
0V—
VOUT -PP (50mV/div)
IOUT (200mA/div)
VOUT (2V/div)–
400mA
0V—
CIN=COUT=22μF (0805)
CIN=COUT=22μF (0805)
0V—
C1=C2=2.2μF (0603)
0mA
C1=C2=2.2μF (0603)
IOUT (200mA/div)–
Time (200μs/div)
Time (10μs/div)
Quiescent Current
Startup (400mA)
VIN=3.6V, IOUT=400mA
2.25
VOUT = 3.3V, IOUT = 1mA
2.00
VEN (2V/div)–
1.75
IQ(mA)
0V —
VOUT (2V/div)–
0V—
IOUT (200mA/div)–
0V—
1.50
25°C
85°C
1.25
-45°C
CIN=COUT=22μF (0805)
1.00
C1=C2=2.2μF (0603)
Time (200μs/div)
0.75
5.50
4.98
4.46
VIN (V)
3.94
3.42
2.90
7
SC630
Pin Descriptions
Pin
Pin Name
Pin Function
1
GND
Ground — connect to ground plane with multiple vias
2
C1+
Positive terminal of bucket capacitor 1
3
C1-
Negative terminal of bucket capacitor 1
4
IN
Input supply voltage
5
EN
Chip enable — active-high
6
OUT
Output
7
C2+
Positive terminal of bucket capacitor 2
8
C2-
Negative terminal of bucket capacitor 2
T
Thermal Pad
This pad is for heat sinking and is not connected internally. It must be connected to a ground plane using
multiple vias.
8
SC630
Block Diagram
IN 4
LDO
2 C1+
200kHz
3 C17 C2+
EN 5
Logic
Control
Reference
Voltage
Generator
CHARGE
PUMP
8 C26 OUT
1 GND
9
SC630
Applications Information
General Description
The SC630 is a 3.3V output charge pump regulator
designed to support up to 400mA (TA ≤ 85°C, 3.15V ≤ VIN ≤
5.5V) of continuous current. It is used for powering Micro
HDDs (Hard Disk Drives) and other 3.3V devices in portable handheld equipment including Compact Flash and
CF+ products.
page 6 to determine if 2x mode is required by the application. The data provided in the following derating curve
for 2x mode is based on the peak power dissipation that
could occur while in 2x mode. 1x and 1.5x modes do not
require derating.
450
400
Mode Transition Hysteresis
Hysteresis is provided to prevent chatter between charge
pump modes for input steps of up to 120mV. Decouple
the input to prevent steps greater than 120mV, for
optimum transient performance, when the input voltage
reaches the mode transition thresholds.
Thermal Resistance
The SC630 package is thermally efficient when the circuit
board layout connects the thermal pad through multiple
vias to the ground plane. The thermal resistance is dependent upon the connection between the thermal pad and
the ground plane. A layout that is done correctly should
keep the junction temperature below the over-temperature limit while operating the SC630 within the specified
electrical conditions. A poor layout may allow the junction temperature to reach the over temperature limit, so
it is important to maintain adequate ground plane around
the device to maximize heat transfer to the PCB.
Temperature Derating
Derating for applications
requiring only 1x and 1.5x
modes
350
IOUT (mA)
The SC630 has three operating modes — 1x, 1.5x, and 2x.
The 1x mode is a linear series regulation mode with a low
output resistance of only 300mΩ. The 1x mode functions
as a low noise series linear regulator. The 1.5x and 2x
modes are a low noise constant frequency, constant duty
cycle switch mode, using two bucket capacitors. One
bucket supports the full output current while the other
bucket charges from the input. The two buckets exchange
roles in the next phase, supplying continuous output
current in both phases and reducing the need for a large
output decoupling capacitor. The constant frequency,
constant duty cycle operation also produces predictable
constant frequency harmonics.
300
Derating for applications
requiring 2x mode
250
200
150
100
35
45
55
65
75
85
Ambient Temperature (°C)
95
105
Maximum Continuous Output
Protection Circuitry
The SC630 also provides protection circuitry that prevents the device from operating in an unspecified state.
These functions include:
•
•
•
Over-Current Protection (OCP)
Short-Circuit Current Protection (SCCP)
Over-Temperature Protection (OTP)
Over-Current Protection
Over-current protection is provided to limit the output
current. When VOUT is greater than 2V, OCP limits the
output to 1A typical. The threshold at 2V allows the device
to recover from excessive voltage droop during an over
current.
Short-Circuit Current Protection
Short-circuit current protection is provided to limit the
current that can be sourced when the output is shorted
to ground. When a short circuit forces VOUT to drop below
2V, the SCCP detects the condition and limits the output
current to 250mA (typical).
The load current and battery voltage range of the application should be compared with the efficiency plots on
10
SC630
Applications Information (continued)
Over-Temperature Protection
The over-temperature circuit helps prevent the device
from overheating and experiencing a catastrophic failure.
When the junction temperature exceeds 165°C the device
is disabled. It remains disabled until the junction temperature drops below this threshold. Hysteresis is included
that prevents the device from re-enabling until the junction temperature is reduced by 20°C.
Capacitor Selection
The SC630 is designed to use low-ESR ceramic capacitors
for the input and output bypass capacitors as well as the
charge pump bucket capacitors. Ideal performance is
achieved when the bucket capacitors are exactly equal.
The value of input and output decoupling capacitors will
vary with system requirements. CIN and COUT are normally
22μF and the bucket capacitors C1 and C2 are 2.2μF. For
low profile designs, two parallel 10μF capacitors may be
used in place of each 22μF.
For applications with load currents below 100 mA, the
bucket capacitors may be reduced to 1μF and the input
and output capacitors may be reduced to 10μF. The following table lists recommended capacitor values. Note
that the smallest available capacitor packages have very
poor DC voltage characteristics. 0402 and 0603 size
capacitors may be as low as 50% of rated value
at 3.3V.
The following capacitors are recommended for best performance. Use only X5R ceramic with a voltage rating of
6.3V or higher.
Table 1 — Recommended Capacitors
Capacitor
Value
μF
Case
Size
Notes
Typical output VPP ≤ 20mV in all
charge pump modes
CIN , COUT
CIN , COUT
22
0805
Typical input ripple ≤ 100mV in all
charge pump modes
10
0805
Typical performance is similar to
the 22uF if 0805 capacitor size is
used, due to the weaker DC voltage coefficient of the 22uF 0805.
Typical output VPP as high as
75mV in boosting charge pump
modes
CIN , COUT
10
0603
Typical input ripple as high as
175mV in boosting charge pump
modes
For a lower profile design, two
10uF 0603’s may be substituted
in place of one 10uF or 22uF
0805. Two are needed, due to the
weaker DC voltage coefficient of
the 0603 package size.
CBUCKET
2.2
0603
Required for the full rated output
current
CBUCKET
2.2
0402
Useful for load current up to
300mA
CBUCKET
1.0
0402
Useful for load current up to
100mA
NOTE: Use only X5R type capacitors, with a 6.3V rating or higher
The highest capacitance values in the smallest package
sizes tend to have poor DC voltage characteristics. The
highest value 0402 size capacitor retains as little as 35% of
its rated value at 5VDC. The same value chosen in the next
larger package size (0603) retains about 60% of its rated
value at 5VDC.
11
SC630
Applications Information (continued)
PCB Layout Considerations
Poor layout can degrade the performance of the regulator and can be a contributory factor in EMI problems,
ground bounce, thermal issues, and resistive voltage
losses. Poor regulation and instability can result.
The following design rules are recommended:
1. Place the bucket capacitors as close to the device as
possible and on the same side of the board. Use short
wide copper areas between the capacitor pins and
the device pins.
2. Place the input and output decoupling capacitors
as close as possible to the device and connect these
capacitors’ ground pads together to the ground plane
using multiple vias through a short wide copper
area.
3. Connect pin 1 directly to the copper area under the
thermal pad.
4. The thermal pad at the center of the device is not
electrically connected. Connect this pad to the
ground plane using multiple vias.
5. Use a ground plane to further reduce noise
interference on sensitive circuit nodes.
SC630
GND
C1
C1+
C2-
C2
C2+
GND
C1-
OUT
IN
EN
COUT
CIN
EN
12
SC630
Outline Drawing — MLPD-UT-8 2x2
B
D
A
DIMENSIONS
DIM
E
PIN 1
INDICATOR
(LASER MARK)
A
SEATING
PLANE
aaa C
A2
A1
C
A
A1
A2
b
D
D1
E
E1
e
L
N
aaa
bbb
INCHES
MIN
.020
.000
NOM
-
MILLIMETERS
MAX
.024
.002
(.006)
.007
.075
.061
.075
.026
.010 .012
.079 .083
.067 .071
.079 .083
.031 .035
.020 BSC
.012
.014 .016
8
.003
.004
MIN
0.50
0.00
NOM
-
(0.1524)
0.18 0.25
1.90 2.00
1.55 1.70
1.90 2.00
0.65 0.80
0.50 BSC
0.30 0.35
8
0.08
0.10
MAX
0.60
0.05
0.30
2.10
1.80
2.10
0.90
0.40
D1
1
2
LxN
E/2
E1
N
bxN
bbb
e
C A B
e/2
D/2
NOTES:
1.
CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES).
2.
COPLANARITY APPLIES TO THE EXPOSED PAD AS WELL AS THE TERMINALS.
13
SC630
Land Pattern — MLPD-UT-8 2x2
H
DIMENSIONS
R
(C)
K
G
Z
Y
P
DIM
INCHES
MILLIMETERS
C
(.077)
(1.95)
G
.047
1.20
H
.067
1.70
K
.031
0.80
P
.020
0.50
R
.006
0.15
X
.012
0.30
Y
.030
0.75
Z
.106
2.70
X
NOTES:
1.
CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES).
2.
THIS LAND PATTERN IS FOR REFERENCE PURPOSES ONLY.
CONSULT YOUR MANUFACTURING GROUP TO ENSURE YOUR
COMPANY'S MANUFACTURING GUIDELINES ARE MET.
3.
THERMAL VIAS IN THE LAND PATTERN OF THE EXPOSED PAD
SHALL BE CONNECTED TO A SYSTEM GROUND PLANE.
FAILURE TO DO SO MAY COMPROMISE THE THERMAL AND/OR
FUNCTIONAL PERFORMANCE OF THE DEVICE.
Contact Information
Semtech Corporation
Power Management Products Division
200 Flynn Road, Camarillo, CA 93012
Phone: (805) 498-2111 Fax: (805) 498-3804
www.semtech.com
14