SSC SS6612

SS6612
High-Efficiency Synchronous Step-up DC/DC
Converter with Selectable Current Limit
DESCRIPTION
FEATURES
High efficiency (93% with VIN=2.4V, VOUT= 3.3V,
IOUT=200mA)
The SS6612 is a high-efficiency step-up
Output current up to 500mA. (VIN=2.4V, at
VOUT=3.3V, CLSEL=OUT)
as 0.8V, and an operating voltage down to 0.7V.
Quiescent supply current of 20µA
this device includes a built-in synchronous rec-
DC/DC converter, with a start-up voltage as low
Consuming only 20µA of quiescent current,
Power-saving shutdown mode (0.1µA typical).
Internal synchronous rectifier (no external diode
required).
Selectable current limit for reduced ripple.
Low-noise, anti-ringing feature.
On-chip low-battery detector.
Low-battery hysteresis.
Space-saving package: MSOP-10
tifier that reduces size and cost by eliminating
the need for an external Schottky diode, and
improves overall efficiency by minimizing
losses.
The switching frequency can range up to
500KHz depending on the load and input voltage. The output voltage can be easily set; by
two external resistors for 1.8V to 5.5V; con-
APPLICATIONS
necting FB to OUT to get 3.3V; or connecting
Palmtop & Notebook Computers.
PDAs
Wireless Phones
Pocket Organizers.
Digital Cameras.
Hand-Held Devices with 1 to 3 Cells of
NiMH/NiCd Batteries.
to GND to get 5.0V. For additional design flexibility, the peak current of the internal switch is
selectable (0.65A or 1.0A). The SS6612 also
features a circuit that eliminates noise caused
by inductor ringing.
TYPICAL APPLICATION CIRCUIT
VIN
+
47µF
200Ω
22µH
BATT
ON
OFF
Selectable Current Limit
(1.0A or 0.65A)
Low Battery
Detection
SHDN
LX
OUT
CLSEL
SS6612
LBI
REF
LBO
GND
FB
Output 3.3V, 5.0V
or Adj. (1.8V to
+
5.5V) up to 300mA
47µF
Low-battery
Detect Out
0.1µF
Rev.2.02 12/06/2003
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SS6612
PIN CONFIGURATION
ORDERING INFORMATION
SS6612CXXX
Packing
TR: Tape and reel
Package type
O: MSOP-10
TOP VIEW
MSOP-10
FB 1
LBI 2
LBO 3
Example: SS6612COTR
in MSOP-10 package supplied
on tape and reel.
10 OUT
9 LX
8 GND
CLSEL 4
7 BATT
REF 5
6 SHDN
ABSOLUTE MAXIMUM RATINGS
Supply Voltage (OUT to GND)
8.0V
VOUT+ 0.3V
Switch Voltage (LX to GND)
Battery Voltage (BATT to GND)
6.0V
SHDN , LBO to GND
6.0V
VOUT+0.3V
LBI, REF, FB, CLSEL to GND
Switch Current (LX)
-1.5A to +1.5A
Output Current (OUT)
-1.5A to +1.5A
Operating Temperature Range
-40°C ~ +85°C
Storage Temperature Range
-65°C ~150°C
TEST CIRCUIT
Refer to the typical application circuit.
Rev.2.02 12/06/2003
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SS6612
ELECTRICAL CHARACTERISTICS
PARAMETER
(VIN = 2.0V, VOUT = 3.3V (FB = VOUT), RL = ∝, TA = 25°C,
unless otherwise specified.)
TEST CONDITIONS
MIN.
Minimum Input Voltage
MAX.
0.7
Operating Voltage
Start-Up Voltage
TYP.
1.1
RL=3kΩ (Note1)
0.8
Start-Up Voltage Temp. Coeff.
V
5.5
V
1.1
V
-2
Output Voltage Range
VIN<VOUT
1.8
Output Voltage
FB = VOUT
3.17
3.3
CLSEL=OUT
300
350
=3.3V) CLSEL=GND
150
300
CLSEL=OUT
180
230
=5.0V) CLSEL=GND
90
160
1.199
1.23
FB=OUT
Steady State Output Current
(VOUT
(Note 2)
FB=GND
UNIT
mV/°C
5.5
3.43
V
mA
(VOUT
Reference Voltage
IREF= 0
Reference Voltage Temp. Coeff.
1.261
0.024
V
mV/°C
Reference Load Regulation
IREF = 0 to 100µA
10
30
mV
Reference Line Regulation
VOUT = 1.8V to 5.5V
5
10
mV/V
1.23
1.261
V
0.3
0.6
Ω
FB, LBI Input Threshold
1.199
Internal switch On-Resistance ILX = 100mA
CLSEL=OUT
0.80
1.0
1.25
CLSEL=GND
0.50
0.65
0.85
0.05
1
µA
VFB = 1.4V , VOUT = 3.3V
20
35
µA
SHDN = GND
0.1
1
µA
VOUT= 3.3V ,ILOAD = 200mA
90
VOUT = 2V ,ILOAD = 1mA
85
LX Switch Current Limit
LX Leakage Current
A
VLX=0V~4V; VOUT=4V
Operating Current into OUT
(Note 3)
Shutdown Current into OUT
Efficiency
Rev.2.02 12/06/2003
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%
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SS6612
ELECTRICAL CHARACTERISTICS
PARAMETER
(Continued)
TEST CONDITIONS
MIN.
TYP.
MAX.
UNIT
LX Switch On-Time
VFB =1V , VOUT = 3.3V
2
4
7
µs
LX Switch Off-Time
VFB =1V , VOUT = 3.3V
0.6
0.9
1.4
µs
FB Input Current
VFB = 1.4V
0.03
50
nA
LBI Input Current
VLBI = 1.4V
1
50
nA
CLSEL Input Current
CLSEL = OUT
1.4
3
µA
SHDN Input Current
V SHDN = 0 or VOUT
0.07
50
nA
LBO Low Output Voltage
VLBI = 0, ISINK = 1mA
0.2
0.4
µA
LBO Off Leakage Current
V LBO = 5.5V, VLBI = 5.5V
0.07
1
LBI Hystereisis
Damping Switch Resistance
50
VBATT = 2V
50
VIL
mV
100
Ω
0.2VOUT
V
SHDN Input Voltage
0.8VOUT
VIH
VIL
0.2VOUT
CLSEL Input Voltage
V
VIH
0.8VOUT
Note 1: Start-up voltage operation is guaranteed without the addition of an external Schottky diode between the
input and output.
Note 2: Steady-state output current indicates that the device maintains output voltage regulation under load.
Note 3: Device is bootstrapped (power to the IC comes from OUT). This correlates directly with the actual battery supply.
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SS6612
TYPICAL PERFORMANCE CHARACTERISTICS
0.5
140
0.4
120
100
Shutdown Current (µA)
Input Battery Current (µA)
160
VOUT=5V (FB=GND)
80
60
40
VOUT=3.3V (FB=OUT)
20
0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
0.1
Fig. 2
1.6
1.4
VOUT=5V (FB=GND)
1.2
1.0
0.8
0.6
VOUT=3.3V (FB=OUT)
0.4
0.2
0.01
0.1
1
10
100
Output Current (mA)
Fig. 3
300
VOUT=5.0V (FB=GND)
0
0.5
1.0
Fig. 4
Ripple Voltage (mV)
VIN=1.2V
VIN=2.4V
VIN=3.6V
30
20
VOUT=5V (FB=GND)
10
CLSEL=OUT (ILIMIT =1A)
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
100
Turning Point between CCM & DCM
CLSEL=OUT (ILIMIT =1A)
160
140
VIN=3.6V
120
100
80
VOUT=5.0V
L=22µH
CIN=47µF
COUT=47µF
VIN=2.4V
60
40
VIN=1.2V
20
1000
0
0
50
100
150
Output Current (mA)
200
250
300
350
400
450
500
550
600
650
Output Current (mA)
Efficiency vs. Output Current (ref. to Fig.35)
Rev.2.02 12/06/2003
5.5
Input Voltage (V)
60
Fig. 5
5.0
50
180
10
4.5
Shutdown Current vs. Supply Voltage
100
80
1
4.0
150
200
0.1
3.5
VOUT=3.3V (FB=OUT)
200
90
0
0.01
3.0
250
220
40
2.5
L=22µH
CIN=100µF
COUT=100µF
350
Start-Up Voltage vs. Output Current
50
2.0
400
100
70
1.5
Supply Voltage (V)
1.8
0.0
1.0
Input battery voltage (V)
No-Load Battery Current vs. Input Battery
CCM/DCM Boundary Output Current (mA)
Fig. 1
Start-Up Voltage (V)
0.2
0.0
0.0
Efficiency (%)
0.3
Fig. 6
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Ripple Voltage (ref. to Fig.35)
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SS6612
TYPICAL PERFORMANCE CHARACTERISTICS
100
240
CLSEL=OUT (ILIMIT =1A)
90
200
80
VIN=3.6V
160
Efficiency (%)
Ripple Voltage (mV)
(Continued)
VIN=2.4V
120
VOUT=5.0V
L=22µH
CIN=100µF
COUT=100µF
80
40
VIN=1.2V
VIN=3.6V
70
VIN=2.4V
60
50
40
30
VOUT=5V (FB=GND)
20
CLSEL=GND (ILIMIT =0.65A)
10
0
0
0
100
200
300
400
500
600
700
800
0.01
0.1
1
Output Current (mA)
Fig. 7
10
100
1000
Output Current (mA)
Ripple Voltage (ref. to Fig.35)
Fig. 8
160
Efficiency vs. Output Current (ref. to Fig.35)
120
CLSEL=GND (ILIMIT =0.65A)
140
CLSEL=GND (ILIMIT =0.65A)
VIN=3.6V
120
100
80
VIN=2.4V
60
VIN=3.6V
100
Ripple Voltage (mV)
Ripple Voltage (mV)
VIN=1.2V
VOUT=5.0V
L=22µH
CIN=47µF
COUT=47µF
40
VIN=1.2V
20
80
60
VOUT=5.0V
L=22µH
CIN=100µF
COUT=100µF
VIN=2.4V
40
20
VIN=1.2V
0
0
0
50
100
150
200
250
300
350
400
450
500
0
550
100
200
Output Current (mA)
Fig. 9
300
400
500
600
Output Current (mA)
Ripple Voltage (ref. to Fig.35)
Fig. 10
100
Ripple Voltage (ref. to Fig.35)
260
CLSEL=OUT (ILIMIT =1A)
240
90
220
80
Efficiency (%)
60
Ripple Voltage (mV)
VIN=1.2V
70
VIN=2.4V
50
40
30
VOUT=3.3V (FB=OUT)
20
CLSEL=OUT (ILIMIT =1A)
10
200
180
160
140
VIN=2.4V
120
100
60
VIN=1.2V
40
20
0
0
0.01
0.1
1
10
100
1000
0
50
100
Output Current (mA)
Fig. 11
VOUT=3.3V
L=22µH
CIN=47µF
COUT=47µF
80
200
250
300
350
400
450
500
550
600
Output Current (mA)
Efficiency vs. Output Current (ref. to Fig.34)
Rev.2.02 12/06/2003
150
Fig. 12
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Ripple Voltage (ref. to Fig.34)
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SS6612
TYPICAL PERFORMANCE CHARACTERISTICS
(Continued)
100
CLSEL=OUT (ILIMIT =1A)
140
90
80
Efficiency (%)
Ripple Voltage (mV)
120
100
VIN=2.4V
VIN=1.2V
80
60
VIN=1.2V
70
50
40
40
VOUT=3.3V
30
VOUT=3.3V (FB=OUT)
20
20
CIN=100µF
COUT=100µF
CLSEL=GND (ILIMIT =0.65A)
10
0
0.01
0
0
50
100
150
200
250
300
350
400
450
500
550
1
Output Current (mA)
Fig. 13
10
100
1000
Output Current (mA)
Ripple Voltage (ref. to Fig.34)
Fig. 14
140
Efficiency vs. Output Current (ref. to Fig.34)
120
CLSEL=GND (ILIMIT =0.65A)
CLSEL=GND (ILIMIT =0.65A)
110
120
100
Ripple Voltage (mV)
Ripple Voltage (mV)
VIN=2.4V
60
100
80
VIN=2.4V
60
VOUT=3.3V
L=22µH
CIN=47µF
COUT=47µF
40
VIN=1.2V
20
90
80
70
60
VIN=2.4V
50
VOUT=3.3V
L=22µH
CIN=100µF
COUT=100µF
40
30
20
VIN=1.2V
10
0
0
0
50
100
150
200
250
300
350
400
450
500
0
50
100
150
Output Current (mA)
Fig. 15
200
250
300
350
400
450
500
Output Current (mA)
Ripple Voltage (ref. to Fig.34)
Fig. 16
1.26
Ripple Voltage (ref. to Fig.34)
0.50
0.45
P-Channel
0.40
Resistance (Ω)
Reference Voltage (V)
1.25
1.24
1.23
1.22
0.35
0.30
N-Channel
0.25
0.20
0.15
VOUT=3.3V
ILX=100mA
0.10
1.21
IREF=0
1.20
-40
-20
0
20
40
60
80
0.05
0.00
-60
-40
-20
Fig. 17
Rev.2.02 12/06/2003
0
20
40
60
80
100
Temperature (°C)
Temperature (°C)
Reference Voltage vs. Temperature
Fig. 18
Switch Resistance vs. Temperature
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SS6612
TYPICAL PERFORMANCE CHARACTERISTICS
900
700
Maximum Output Current (mA)
Maximum Output Current (mA)
800
VOUT=3.3V (FB=OUT)
600
CLSEL=OUT (ILIMIT=1A)
500
400
300
200
CLSEL=GND (ILIMIT=0.65A)
100
0
1.0
1.2
1.4
1.6
1.8
2.0
2.2
2.4
2.6
2.8
800
VOUT=5V (FB=GND)
700
600
CLSEL=OUT (ILIMIT=1A)
500
400
300
200
CLSEL=GND (ILIMIT=0.65A)
100
0
3.0
Input Voltage (V)
Maximum Output Current vs. Input Voltage
Fig. 19
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
Input Voltage (V)
Maximum Output Current vs. Input Voltage
Fig. 20
1.2
160
Switching Frequency fosc (kHz)
CLSEL=OUT (ILIMIT=1A)
1.0
0.8
ILIM (A)
(Continued)
0.6
CLSEL=GND (ILIMIT=0.65A)
0.4
0.2
0.0
2.0
2.5
Fig. 21
3.0
3.5
4.0
4.5
5.0
Output Voltage (V)
Inductor Current vs. Output Voltage
140
120
VOUT=5.0V
100
80
VOUT=3.3V
60
40
IOUT=100mA
20
0
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
Supply Voltage (V)
Fig. 22
Switching Frequency vs. Supply Voltage
Switching Frequency fosc (kHz)
220
200
VIN=1.2V
VOUT=3.3V
180
160
VIN=2.4V
VOUT=3.3V
W /o Anti-Ringing
V IN =2.4V
V OUT =3.3V
140
120
VIN=2.4V
VOUT=5V
100
80
60
40
VIN=3.6V
VOUT=5V
20
0
1
10
100
1000
Output Current (mA)
Fig. 23
Switching Frequency vs. Output Current
Rev.2.02 12/06/2003
Fig. 24
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Without Anti-Ringing Function
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SS6612
TYPICAL PERFORMANCE CHARACTERISTICS
(Continued)
LX Pin W aveform
W i t h A n t i - Ringing
V IN =2.4V
V IN =2.4V
V O U T =3.3V
V OUT =3.3V
Loading=200m A
Inductor C urrent
V O UT A C C ouple
Fig. 25
W ith Anti-Ringing Function
Loading:
1m A
F ig. 26 H eavy Load W aveform
↔ 200m A
VIN
VIN=2.0V~3.0V
V IN =2.4V
V O U T =3.3V
VOUT=3.3V, IOUT=100mA
V O U T : A C C ouple
VOUT
F ig. 27
Load Transient R esponse
Fig. 28
V SHDN
Line Transient Response
V SHDN
VOUT
VOUT
VOUT=3.3V
VOUT=3.3V
CIN=COUT=100µF
C IN=COUT=47µF
Fig. 29
Rev.2.02 12/06/2003
Exiting Shutdown
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Fig. 30
Exiting Shutdown
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SS6612
TYPICAL PERFORMANCE CHARACTERISTICS
(Continued)
V SHDN
V SHDN
VOUT
Fig. 31
V OUT
VOUT=5.0V
V OUT =5.0V
CIN=COUT=47µF
C IN =C OUT =100µF
Exiting Shutdown
Fig. 32
Exiting Shutdown
BLOCK DIAGRAM
OUT
SHDN
CLSEL
OUT
+
Minimum Off-Time
0.1µF
Damping
Q1
Switch
One Shot
Q3
BATT
R1
200Ω
VIN
L
LX
Q2
47µH
F/ F
S
Q
C3
47µF
+
C1
47µF
GND
R
-
One Shot
+
Mirror
Maximum On-Time
FB
+
LBO
+
Reference Voltage
REF
C4
0.1µF
LBI
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SS6612
PIN DESCRIPTIONS
PIN 1: FB-
Connected to OUT to get +3.3V
output, connected to GND to get
+5.0V output, or using a resistor
network to set output voltage ranging from +1.8V to +5.5V.
PIN 2: LBILow-battery comparator input internally set at +1.23V to trip.
PIN 3: LBO- Open-drain low battery comparator
output. Output is low when VLBI is
<1.23V. LBO is high impedance
during shutdown.
PIN 4: CLSEL- Current-limit select input. CLSEL=
OUT sets the current limit to 1.0A.
CLSEL=GND sets the current limit
to 0.65A.
PIN 5: REF-
1.23V reference voltage. Bypass
with a 0.1µF capacitor.
PIN 6: SHDN- Shutdown input. High=operating,
low=shutdown.
PIN 7: BATT- Battery input and damping
switch connection. If damping
switch is unused, leave BATT
unconnected.
PIN 8: GND- Ground.
PIN 9: LXN-channel and P-channel power
MOSFET drain.
PIN 10: OUT- Power output. OUT provides
bootstrap power to the IC.
APPLICATION INFORMATION
Overview
BLOCK DIAGRAM) with ultra-low quiescent current.
The SS6612 is a high-efficiency, step-up DC/DC
The peak current of the internal N-MOSFET power
converter, featuring a built-in synchronous
switch is selectable. The switch frequency depends
rectifier, which reduces size and cost by eliminating
on either loading conditions or input voltage, and can
the need for an external Schottky diode. The start-up
range up to 500KHz. It is governed by a pair of one-
voltage of the SS6612 is as low as 0.8V and it operates
shots that set a minimum off-time (1µs ) and a
with an input voltage down to 0.7V. Quiescent supply
maximum on-time (4µs ).
current is only 20µA. In addition, the SS6612 features a
circuit that eliminates inductor ringing to reduce
Synchronous Rectification
noise. The internal P-MOSFET on-resistance is typi-
Using the internal synchronous rectifier eliminates
cally 0.3Ω to improve overall efficiency by minimizing
the need for an external Schottky diode, reducing
AC losses. The output voltage can be easily set; by
the cost and board space. During the cycle of off-
two external resistors for 1.8V to 5.5V; connecting
time, the P-MOSFET turns on and shuts the N-
FB to OUT to get 3.3V; or connecting to GND to get
MOSFET off. Due to the low turn-on resistance
5.0V. The CLSEL pin offers a selectable current
of the MOSFET, the synchronous rectifier signifi-
limit (1.0A or 0.65A). The lower current limit allows
cantly improves efficiency without an additional ex-
the use of a physically smaller inductor in space-
ternal Schottky diode. Thus, the conversion effi-
sensitive applications.
ciency can be as high as 93%.
PFM Control Scheme
Reference Voltage
A key feature of the SS6612 is a unique minimum-
The reference voltage (REF) is nominally 1.23V for
off-time, constant-on-time, current-limited, pulse-
excellent T.C. performance. In addition, the REF pin can
frequency-modulation (PFM) control scheme (see
source up to 100µA to an external circuit with good load
Rev.2.02 12/06/2003
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SS6612
regulation (<10mV). A bypass capacitor of 0.1µF is
required for proper operation and good performance.
Low-Battery Detection
The SS6612 contains an on-chip comparator with 50mV
internal hysteresis (REF, REF+50mV) for low battery
Shutdown
detection. If the voltage at LBI falls below the internal
The whole circuit is shutdown when V SHDN is low. In
reference voltage, LBO (an open-drain output) sinks
shutdown mode, the current can flow from the battery
current to GND.
to the output due to the body diode of the P-MOSFET.
VOUT falls to approximately (Vin - 0.6V) and LX remains
high impedance. The capacitance and load at OUT de-
Component Selection
termine the rate at which VOUT decays. Shutdown
1. Inductor Selection
can be pulled as high as 6V, regardless of the volt-
An inductor value of 22µH performs well in most
age at OUT.
applications. The SS6612 also works with
inductors in the 10µH to 47µH range. An inductor
Current Limit Select Pin
with higher peak inductor current creates a higher
The SS6612 allows a selectable inductor current limit
output voltage ripple (IPEAK×output filter capaci-
of either 1.0A or 0.65A, allowing the flexibility to design
tor ESR). The inductor’s DC resistance signifi-
for higher current or smaller applications. CLSEL
cantly affects efficiency. We can calculate the
draws 1.4µA when connecting to OUT.
BATT/Damping Switch
The SS6612 is designed with an internal damping
maximum output current as follows:
VIN 
 VOUT − VIN 
IOUT(MAX ) =
ILIM − t OFF 
 η
VOUT 
2×L


switch (Fig.33) to reduce ringing at LX. The damping
........................................................................(2)
where IOUT(MAX)=maximum output current in
switch supplies a path to quickly dissipate the energy
amps
stored in the inductor and reduces the ringing at LX.
VIN=input voltage
Damping LX ringing does not reduce VOUT ripple,
L=inductor value in µH
but does reduce EMI. R1=200Ω works well for most
applications while reducing efficiency by only 1%.
Larger R1 values provide less damping, but less impact on efficiency. In principle, a lower value of R1 is
needed to fully damp LX when VOUT /VIN ratio is high.
η=efficiency (typically 0.9)
tOFF=LX switch’ off-time in µs
ILIM=1.0A or 0.65A
2. Capacitor Selection
The output ripple voltage is related to the peak
Selecting the Output Voltage
inductor current and the output capacitor ESR.
VOUT can be simply set to 3.3V/5.0V by connecting the
FB pin to OUT/GND due to the use of an internal resis-
Besides output ripple voltage, the output ripple
tor divider in the IC (Fig.34 and Fig.35). In order to
with low ESR is helpful to the efficiency and the
adjust the output voltage, a resistor divider is connected
to VOUT, FB, GND (Fig.36). Vout can be calculated
by the following equation:
current may also be of concern. A filter capacitor
steady state output current of the SS6612.
Therefore a NIPPON MCM series tantalum
capacitor of 100µF/6V is recommended. A smaller
R5 = R6 [(VOUT / VREF )-1] .....................................(1)
capacitor (down to 47µF with higher ESR) is ac-
where V REF =1.23V and VOUT ranges from 1.8V to
ceptable for light loads or in applications that can
5.5V. The recommended R6 is 240kΩ.
tolerate higher output ripple.
Rev.2.02 12/06/2003
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12 of 16
SS6612
3. PCB Layout and Grounding
and efficiency, and minimize output ripple voltage,
Since the SS6612’s switching frequency can
use a ground plane and solder the IC’s GND di-
range up to 500kHz, the SS6612 can be very
rectly to the ground plane. Fig.37 to 39 are the
sensitive. Careful printed circuit layout is im-
recommended layout diagrams.
portant for minimizing ground bounce and noise.
The OUT pin should be as clear as possible,
Ripple Voltage Reduction
and the GND pin should be placed close to the
Two or three parallel output capacitors can sig-
ground plane. Keep the IC’s GND pin and the
nificantly improve the output ripple voltage of the
ground leads of the input and output filter capaci-
SS6612. The addition of an extra input capaci-
tors less than 0.2in (5mm) apart. In addition,
tor results in a stable output voltage. Fig.40
keep all connections to the FB and LX pins as
shows the application circuit with the above fea-
short as possible. In particular, when using ex-
tures. Fig. 41 to 48 show the performance of
ternal feedback resistors, locate them as close
Fig.40.
to the FB as possible. To maximize output power
APPLICATION EXAMPLES
VIN
VOUT
R1
200Ω
OUT
DAMPING
SWITCH
Q3
Q1
L
22µH
LX
BATT
BATT
LX
R1
200Ω
0.1µF
R2
100KΩ
REF
LBO
GND
SS6612
Fig.33 Simplified Damping Switch Diagram
Fig.34 VOUT = 3.3V Application Circuit.
VIN
VIN
L
22µH
R1
200Ω
L
22µH
R1
200Ω
C1
47µF
VOUT
OUT
VOUT
OUT
R3
CLSEL
C2
0.1µF
C3
47µF
R3
R2
100KΩ
REF
CLSEL
SHDN
R4
GND
FB
0.1µF
C4
SS6612
Fig.35 VOUT = 5.0V Application Circuit.
C3
47µF
R5
LBO
GND
LOW BATTERY
OUTPUT
FB
SS6612
LOW BATTERY
OUTPUT
L: TDK SLF7045T-22OMR90
C1, C3: NIPPON Tantalum Capacitor 6MCM476MB2TER
100KΩ
R2
REF
LBO
C4
C2
0.1µF
LBI
SHDN
R4
C1
47µF
LX
BATT
LX
BATT
Rev.2.02 12/06/2003
LOW BATTERY
OUTPUT
FB
SS6612
L: TDK SLF7045T-22OMR90
C1, C3: NIPPON Tantalum Capacitor 6MCM476MB2TER
GND
0.1µF
C3
47µF
SHDN
R4
C4
LBI
C2
0.1µF
CLSEL
LBI
VIN
22µH
Q2
VOUT
OUT
R3
L1
C1
47µF
R6
L: TDK SLF7045T-22OMR90
C1, C3: NIPPON Tantalum Capacitor 6MCM476MB2TER
V OUT=V REF*(1+R5/R6)
Fig.36 An Adjustable Output Application Circuit
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13 of 16
SS6612
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Fig.37 Top layer
Fig.38 Bottom layer
Connect to OUT for 3.3V output voltage
Connect to GND for 5.0V output voltage
Open for adjustable output voltage; VOUT=1.23(1+R5/R6)
JU1
R5
VOUT
VIN
R6
1
R3
2
R4
100K
R2
VOUT
3
JU2
Connect to OUT for 1.0A limit
Connect to GND for 0.8A limit
FB
OUT 10
LBI
LX 9
GND 8
4
LBO
CLSEL BATT 7
5
SHDN 6
Fig.39 Placement
VIN
VIN
L1
+
22µH
+ C2
6V/100uF
C1
6V/100µF
D1 is Optional
VOUT
R1
200
REF
SS6612
VIN
+
C4
1µF
+
C5
6V/100µF
+
C6
6V/100µF
C7
6V/100µF
JU3
C3
0.1µF
Connect to GND for shutdown
Connect to VOUT for normal
L1: TDK SLF7045T-22OMR90
C1~C2, C5~7: NIPPON Tantalum Capacitor 6MCM107MCTER
Fig.40 SS6612 application circuit with small ripple voltage
100
95
60
VIN=3.6V
CLSEL=OUT (ILIMIT =1A)
90
50
Ripple Voltage (mV)
85
Efficiency (%)
80
VIN=2.4V
75
70
65
60
CLSEL=OUT (ILIMIT =1A)
55
50
30
20
VIN=2.4V
VOUT=5.0V
45
40
VIN=3.6V
40
VIN=1.2V
L=22µH
L=22µH
35
30
0.01
VOUT=5.0V
VIN=1.2V
10
0
0.1
1
10
100
1000
0
100
Output Current (mA)
Fig. 41
Rev.2.02 12/06/2003
200
300
400
500
600
700
Output Current (mA)
Efficiency (ref. to Fig.40)
Fig. 42
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Ripple Voltage (ref. to Fig.40)
14 of 16
SS6612
60
95
90
60
CLSEL=GND (ILIMIT =0.65A)
VIN=3.6V
50
Ripple Voltage (mV)
85
Efficiency (%)
80
75
70
VIN=2.4V
65
60
55
CLSEL=GND (ILIMIT =0.65A)
50
45
40
VIN=3.6V
40
30
20
VIN=2.4V
VOUT=5.0V
VIN=1.2V
10
35
VIN=1.2V
L=22µH
30
25
0.01
0.1
1
Fig. 43
10
100
1000
0
100
200
Efficiency (ref. to Fig.40)
Fig. 44
VIN=2.4V
Ripple Voltage (mV)
Efficiency (%)
CLSEL=OUT (ILIMIT =1A)
40
80
75
70
VIN=1.2V
65
60
CLSEL=OUT (ILIMIT =1A)
VOUT=3.3V
35
30
25
VIN=2.4V
20
15
10
L=22µH
45
VOUT=3.3V
VIN=1.2V
L=22µH
5
0
40
0.01
0.1
1
10
100
0
1000
50
100
150
Output Current (mA)
Fig. 45
200
250
300
350
400
450
500
550
600
Output Current (mA)
Efficiency (ref. to Fig.40)
Fig. 46
Ripple Voltage (ref. to Fig.40)
35
100
CLSEL=GND (ILIMIT =0.65A)
95
30
90
80
Ripple Voltage (mV)
85
Efficiency (%)
500
Ripple Voltage (ref. to Fig.40)
45
85
VIN=2.4V
75
70
65
60
CLSEL=GND (ILIMIT =0.65A)
55
50
400
50
90
50
300
Output Current (mA)
100
55
L=22µH
0
Output Current (mA)
95
VOUT=5.0V
25
20
VIN=2.4V
15
10
VOUT=3.3V
VIN=1.2V
L=22µH
45
40
0.01
L=22µH
0
0.1
1
10
100
1000
0
50
100
Output Current (mA)
150
200
250
300
350
400
Output Current (mA)
Fig. 47 Efficiency (ref. to Fig.40)
Rev.2.02 12/06/2003
VOUT=3.3V
VIN=1.2V
5
Fig. 48
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Ripple Voltage (ref. to Fig.40)
15 of 16
SS6612
PHYSICAL DIMENSIONS
10 LEAD MSOP (unit: mm)
D
SYMBOL
MIN
MAX
A1
--
0.20
A2
0.76
0.97
b
0.15
0.30
C
0.13
0.23
D
2.90
3.10
E
4.80
5.00
E1
2.90
3.10
E
E1
e
A2
e
C
0.40
0.66
A1
L
0.50
b
L
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responsibility for its use, or for infringement of any patent or other intellectual property rights of third parties that may result from its
use. Silicon Standard reserves the right to make changes as it deems necessary to any products described herein for any reason, including
without limitation enhancement in reliability, functionality or design. No license is granted, whether expressly or by implication, in relation to
the use of any products described herein or to the use of any information provided herein, under any patent or other intellectual property rights of
Silicon Standard Corporation or any third parties.
Rev.2.02 12/06/2003
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