AIC1612
High Efficiency Selectable Current Limit
Synchronous Step-Up DC/DC Converter
Analog Integrations Corporation 4F, 9 Industry E. 9th Rd, Science-Based Industrial Park, Hsinchu, Taiwan DS-1612-01 080703
TEL: 886-3-5772500 FAX: 886-3-5772510 www.analog.com.tw 1
FEATURES
High Efficiency (93% when VIN=2.4V,
VOUT=3.3V, IOUT=200mA)
Output Current up to 500mA. (VIN=2.4V, at
VOUT=3.3V, CLSEL=OUT)
20µA Quiescent Supply 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
APPLICATIONS
Palmtop & Notebook Computers.
PDAs
Wireless Phones
Pocket Organizers.
Digital Cameras.
Hand-Held Devices with 1 to 3-Cell of
NiMH/NiCd Batteries.
DESCRIPTION
AIC1612 is a high efficiency step-up DC-DC
converter. The start-up voltage is as low as
0.8V with operating voltage down to 0.7V.
Simply consuming 20µA of quiescent current,
these devices offer a built-in synchronous rec-
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 volt-
age. The output voltage can be easily set by
two external resistors from 1.8V to 5.5V, con-
necting FB to OUT to get 3.3V, or connecting
to GND to get 5.0V. In terms of design flexibil-
ity, the peak current of internal switch is se-
lectable (0.65A or 1.0A). AIC1612 also fea-
tures a circuit that eliminates noise due to in-
ductor ringing.
TYPICAL APPLICATION CIRCUIT
Output 3.3V, 5.0V
or Adj. (1.8V to
5.5V) up to 300mA
Low-battery
Detect Out
AIC1612
OUT
FB
GNDREF
LBO
SHDN LX
LBI
+
ON OFF
+
Low Battery
Detection
0.1µF
VIN
22µH
47µF
47µF
Selectable Current Limit
(1.0A or 0.65A) CLSEL
200Ω
BATT
AIC1612
2
ORDERING INFORMATION
A
IC1612CXXX PIN CONFIGURATION
TOP VIEW
1
3
4
2
10
8
7
9
FB
LBI
LBO
CLSEL
REF
OUT
LX
GND
BATT
SHDN
56
(MSOP10)
Example: AIC1612COTR
In MSO10 Package & Taping &
Reel Packing Type
PACKING TYPE
TR: TAPE & REEL
PACKAGING TYPE
O: MSOP10
ABSOLUTE MAXIMUM RATINGS
Supply Voltage (OUT to GND) 8.0V
Switch Voltage (LX to GND) VOUT+ 0.3V
Battery Voltage (BATT to GND) 6.0V
, LBO to GND 6.0V
LBI, REF, FB, CLSEL to GND VOUT+0.3V
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 Typical Application Circuit.
SHDN
AIC1612
3
ELECTRICAL CHARACTERISTICS (VIN=2.0V, VOUT=3.3V (FB=VOUT), RL=∝, TA=25°C,
unless otherwise specified.)
PARAMETER TEST CONDITIONS MIN. TYP. MAX. UNIT
Minimum Input Voltage 0.7 V
Operating Voltage 1.1 5.5 V
Start-Up Voltage RL=3KΩ (Note1) 0.8 1.1 V
Start-Up Voltage Tempco -2 mV/°C
Output Voltage Range VIN<VOUT 1.8 5.5
Output Voltage FB = VOUT 3.17 3.3 3.43 V
CLSEL=OUT 300 350
FB=OUT
(VOUT =3.3V) CLSEL=GND 150 300
CLSEL=OUT 180 230
Steady State Output Current
(Note 2) FB=GND
(VOUT =5.0V) CLSEL=GND 90 160
mA
Reference Voltage IREF= 0 1.199 1.23 1.261 V
Reference Voltage Tempco 0.024 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
FB , LBI Input Threshold 1.199 1.23 1.261 V
Internal switch On-Resistance ILX = 100mA 0.3 0.6 Ω
CLSEL=OUT 0.80 1.0 1.25
LX Switch Current Limit
CLSEL=GND 0.50 0.65 0.85
A
LX Leakage Current VLX=0V~4V; VOUT=4V 0.05 1 µA
Operating Current into OUT
(Note 3) VFB = 1.4V , VOUT = 3.3V 20 35 µA
Shutdown Current into OUT SHDN = GND 0.1 1 µA
VOUT= 3.3V ,ILOAD = 200mA 90
Efficiency
VOUT = 2V ,ILOAD = 1mA 85
%
AIC1612
4
ELECTRICAL CHARACTERISTICS (Continued)
PARAMETER 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 VSHDN = 0 or VOUT 0.07 50 nA
LBO Low Output Voltage VLBI = 0, ISINK = 1mA 0.2 0.4 µA
LBO Off Leakage Current VLBO = 5.5V, VLBI = 5.5V 0.07 1
LBI Hystereisis 50 mV
Damping Switch Resistance VBATT = 2V 50 100 Ω
VIL 0.2VOUT
SHDN Input Voltage
VIH 0.8VOUT
V
VIL 0.2VOUT
CLSEL Input Voltage
VIH 0.8VOUT
V
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 bat-
tery supply.
AIC1612
5
TYPICAL PERFORMANCE CHARACTERISTICS
Input Battery Current (µA)
Input battery voltage (V)
Fig. 1 No-Load Battery Current vs. Input Battery
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5
0
20
40
60
80
100
120
140
160
VOUT=5V (FB=GND)
VOUT=3.3V (FB=OUT)
Shutdown Current Current (µA)
Supply Voltage (V)
Fig. 2 Shutdown Current vs. Supply Voltage
1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5
0.0
0.1
0.2
0.3
0.4
0.5
Fig. 3 Start-Up Voltage vs. Output Current
Start-U
p
Volta
g
e
(
V
)
0.01 0.1 1 10 100
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
VOUT=5V (FB=GND)
Output Current (mA)
VOUT=3.3V (FB=OUT)
Fig. 4 Turning Point between CCM & DCM
CCM/DCM Boundary Output Current (mA)
Input Voltage (V)
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
0
50
100
150
200
250
300
350
400
VOUT=5.0V (FB=GND)
VOUT=3.3V (FB=OUT)
L=22µH
CIN=100µF
COUT=100µF
Fig. 5 Efficiency vs. Output Current (ref. to Fig.35)
Efficiency (%)
0.01 0.1 1 10 100 1000
0
10
20
30
40
50
60
70
80
90
100
VIN=3.6V
Output Current (mA)
VIN=2.4V
VIN=1.2V
CLSEL=OUT (ILIMIT =1A)
VOUT=5V (FB=GND)
Fig. 6 Ripple Voltage (ref. to Fig.35)
Ripple Voltage (mV)
Output Current (mA)
050 100 150 200 250 300 350 400 450 500 550 600 650
0
20
40
60
80
100
120
140
160
180
200
220
VIN=2.4V
VIN=1.2V
VOUT=5.0V
L=22µH
CIN=47µF
COUT=47µF
VIN=3.6V
CLSEL=OUT (ILIMIT =1A)
AIC1612
6
TYPICAL PERFORMANCE CHARACTERISTICS (Continued)
Fig. 7 Ripple Voltage (ref. to Fig.35)
Ripple Voltage (mV)
Output Current (mA)
0 100 200 300 400 500 600 700 800
0
40
80
120
160
200
240
VIN=2.4V
VOUT=5.0V
L=22µH
CIN=100µF
COUT=100µF
VIN=3.6V
VIN=1.2V
CLSEL=OUT (ILIMIT =1A)
Fig. 8 Efficiency vs. Output Current (ref. to Fig.35)
Efficiency (%)
Output Current (mA)
0.01 0.1 110 100 1000
0
10
20
30
40
50
60
70
80
90
100
VIN=3.6V
VIN=1.2V
VIN=2.4V
CLSEL=GND (ILIMIT =0.65A)
VOUT=5V (FB=GND)
Fig. 9 Ripple Voltage (ref. to Fig.35)
Ripple Voltage (mV)
Output Current (mA)
0 50 100 150 200 250 300 350 400 450 500 550
0
20
40
60
80
100
120
140
160
VOUT=5.0V
L=22µH
CIN=47µF
COUT=47µF
VIN=3.6V
VIN=2.4V
VIN=1.2V
CLSEL=GND (ILIMIT =0.65A)
Fig. 10 Ripple Voltage (ref. to Fig.35)
Ripple Voltage (mV)
Output Current (mA)
0100 200 300 400 500 600
0
20
40
60
80
100
120
VIN=2.4V
VIN=1.2V
VOUT=5.0V
L=22µH
CIN=100µF
COUT=100µF
VIN=3.6V
CLSEL=GND (ILIMIT =0.65A)
Fig. 11 Efficiency vs. Output Current (ref. to Fig.34)
(V) Efficiency (%)
Output Current (mA)
0.01 0.1 1 10 100 1000
0
10
20
30
40
50
60
70
80
90
100
VIN=2.4V
VIN=1.2V
CLSEL=OUT (ILIMIT =1A)
VOUT=3.3V (FB=OUT)
Fig. 12 Ripple Voltage (ref. to Fig.34)
Ripple Voltage (mV)
Output Current (mA)
050 100 150 200 250 300 350 400 450 500 550 600
0
20
40
60
80
100
120
140
160
180
200
220
240
260
VIN=1.2V
VOUT=3.3V
L=22µH
CIN=47µF
COUT=47µF
VIN=2.4V
CLSEL=OUT (ILIMIT =1A)
AIC1612
7
TYPICAL PERFORMANCE CHARACTERISTICS (Continued)
Fig. 13 Ripple Voltage (ref. to Fig.34)
Ripple Voltage (mV)
Output Current (mA)
0 50 100 150 200 250 300 350 400 450 500 550
0
20
40
60
80
100
120
140
VOUT=3.3V
CIN=100µF
COUT=100µF
VIN=1.2V VIN=2.4V
AIC1610 (ILIMIT =1A)
CLSEL=OUT (ILIMIT =1A)
Fig. 14 Efficiency vs. Output Current (ref. to Fig.34)
Efficiency (%)
Output Current (mA)
0.01 110 100 1000
0
10
20
30
40
50
60
70
80
90
100
VIN=1.2V VIN=2.4V
CLSEL=GND (ILIMIT =0.65A)
VOUT=3.3V (FB=OUT)
Fig. 15 Ripple Voltage (ref. to Fig.34)
Ripple Voltage (mV)
Output Current (mA)
0 50 100 150 200 250 300 350 400 450 500
0
20
40
60
80
100
120
140
VOUT=3.3V
L=22µH
CIN=47µF
COUT=47µF
VIN=1.2V
VIN=2.4V
CLSEL=GND (ILIMIT =0.65A)
Fig. 16 Ripple Voltage (ref. to Fig.34)
Ripple Voltage (mV)
Output Current (mA)
050 100 150 200 250 300 350 400 450 500
0
10
20
30
40
50
60
70
80
90
100
110
120
VOUT=3.3V
L=22µH
CIN=100µF
COUT=100µF
VIN=1.2V
VIN=2.4V
CLSEL=GND (ILIMIT =0.65A)
Fig. 17 Reference Voltage vs. Temperature
Reference Voltage (V)
Temperature (°C)
-40 -20 0 20 40 60 80
1.20
1.21
1.22
1.23
1.24
1.25
1.26
IREF=0
Fig. 18 Switch Resistance vs. Temperature
Resistance (Ω)
Temperature (°C)
-60 -40 -20 020 40 60 80 100
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
0.45
0.50
P-Channel
N-Channel
VOUT=3.3V
ILX=100mA
AIC1612
8
TYPICAL PERFORMANCE CHARACTERISTICS (Continued)
Fig. 19 Maximum Output Current vs. Input Voltage
Maximum Output Current (mA)
1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 2.8 3.0
0
100
200
300
400
500
600
700
800
Input Voltage (V)
CLSEL=GND (ILIMIT=0.65A)
CLSEL=OUT (ILIMIT=1A)
VOUT=3.3V (FB=OUT)
Input Voltage (V)
Fig. 20 Maximum Output Current vs. Input Voltage
Maximum Output Current (mA)
1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5
0
100
200
300
400
500
600
700
800
900
CLSEL=GND (ILIMIT=0.65A)
CLSEL=OUT (ILIMIT=1A)
VOUT=5V (FB=GND)
Fig. 21 Inductor Current vs. Output Voltage
ILIM
(
A
)
Output Voltage (V)
2.0 2.5 3.0 3.5 4.0 4.5 5.0
0.0
0.2
0.4
0.6
0.8
1.0
1.2
CLSEL=OUT (ILIMIT=1A)
CLSEL=GND (ILIMIT=0.65A)
Supply Voltage (V)
Fig. 22 Switching Frequency vs. Supply Voltage
Switching Frequency fosc (KHz)
1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5
0
20
40
60
80
100
120
140
160
IOUT=100mA
VOUT=5.0V
VOUT=3.3V
Switching Frequency Fosc (KHz)
Output Current (mA)
1 10 100 1000
0
20
40
60
80
100
120
140
160
180
200
220
VIN=2.4V
VOUT=3.3V
VIN=1.2V
VOUT=3.3V
VIN=2.4V
VOUT=5V
VIN=3.6V
VOUT=5V
Fig. 23 Switching Frequency vs. Output Current
W/o Damping Ringing
VIN=2.4V
VOUT=3.3V
Fig. 24 W ithout Damping Ringing Function
AIC1612
9
TYPICAL PERFORMANCE CHARACTERISTICS (Continued)
W. Damping Ringing
VIN=2.4V
VOUT=3.3V
Fig. 25 With Damping Ringing Function
VIN=2.4V
VOUT=3.3V
Loading=200mA
LX Pin Waveform
Inductor Current
VOUT AC Couple
Fig. 26 Heavy Load Waveform
Loading: 1mA ↔ 200mA
VIN=2.4V
VOUT=3.3V VOUT: AC Couple
Fig. 27 Load Transient Response
VIN=2.0V~3.0V
VOUT=3.3V, IOUT=100mA
VOUT
Fig. 28 Line Transient Response
VIN
Fig. 29 Exiting Shutdown
VOUT
VSHDN
VOUT=3.3V
CIN=COUT=47µF
Fig. 30 Exiting Shutdown
VSHDN
VOUT
VOUT=3.3V
CIN=COUT=100µF
AIC1612
10
TYPICAL PERFORMANCE CHARACTERISTICS (Continued)
Fig. 31 Exiting Shutdown
VSHDN
VOUT
VOUT=5.0V
CIN=COUT=47µF
Fig. 32 Exiting Shutdown
VOUT
VSHDN
VOUT=5.0V
CIN=COUT=100µF
BLOCK DIAGRAM
+
-
+
-
+
-
+
-
+
47
µ
F
47µF
47µH
R1
L
200Ω
FB
REF
GND
LX
BATT
OUT
Q3
Switch
Damping
C4
0.1µF
C1
0.1
µ
F C3
OUT
VIN
LBO
LBI
CLSEL
SHDN
F/ F
Q
R
S
Q2
Q1
Reference Voltage
Mirror
Maximum On-Time
One Shot
Minimum Of
f
-Time
One Shot
AIC1612
11
PIN DESCRIPTIONS
PIN 1: FB- Connecting to OUT to get +3.3V
output, connecting to GND to get
+5.0V output, or using a resistor
network to set output voltage rang-
ing from +1.8V to +5.5V.
PIN 2: LBI- Low-Battery comparator input inter-
nally sets 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 selects 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: LX- N-channel and P-channel power
MOSFET drain.
PIN 10: OUT- Power output. OUT provides
bootstrap power to the IC.
APPLICATION INFORMATION
Overview
AIC1612 is a high efficiency, step-up DC-DC con-
verter, designed to feature a built-in synchronous
rectifier, which reduces size and cost by eliminating
the need for an external Schottky diode. The start-up
voltage of AIC1612 is as low as 0.8V and it operates
with an input voltage down to 0.7V. Quiescent supply
current is only 20µA. In addition, AIC1612 features a
circuit that eliminates inductor ringing to reduce
noise. The internal P-MOSFET on-resistance is typi-
cally 0.3Ω to improve overall efficiency by minimizing
AC losses. The output voltage can be easily set by
two external resistors from 1.8V to 5.5V, connecting
FB to OUT to get 3.3V, or connecting to GND to get
5.0V. CLSEL pin of AIC1612 offers a selectable cur-
rent limit (1.0A or 0.65A). The lower current limit al-
lows the use of a physically smaller inductor in
space-sensitive applications.
PFM Control Scheme
The key feature of AIC1612 is a unique minimum-
off-time, constant-on-time, current-limited, pulse-
frequency-modulation (PFM) control scheme (see
BLOCK DIAGRAM) with ultra-low quiescent current.
The peak current of the internal N-MOSFET power
switch is selectable. The switch frequency depends
on either loading condition or input voltage, and can
range up to 500KHz. It is governed by a pair of one-
shots that set a minimum off-time (1µS) and a
maximum on-time (4µS).
Synchronous Rectification
Using the internal synchronous rectifier eliminates
the need for an external Schottky diode. Therefore,
the cost and board space are reduced. During the
cycle of off-time, P-MOSFET turns on and shuts N-
MOSFET off. Due to the low turn-on
resistance of MOSFET, synchronous rectifier signifi-
cantly improves efficiency without an additional ex-
ternal Schottky diode. Thus, the conversion effi-
ciency can be as high as 93%.
Reference Voltage
The reference voltage (REF) is nominally 1.23V for
excellent T.C. performance. In addition, REF pin can
source up to 100µA to external circuit with good load
AIC1612
12
regulation (<10mV). A bypass capacitor of 0.1µF is
required for proper operation and good performance
Shutdown
The whole circuit is shutdown when SHDNV is low. At
shutdown mode, the current can flow from battery to
output due to the body diode of P-MOSFET. VOUT
falls to approximately Vin-0.6V and LX remains high
impedance. The capacitance and load at OUT de-
termine the rate at which VOUT decays. Shutdown
can be pulled as high as 6V, regardless of the volt-
age at OUT.
Current Limit Select Pin
AIC1612 allows a selectable inductor current limit of
either 1.0A or 0.65A. The flexibility contributes to de-
signs for higher current or smaller applications.
CLSEL draws 1.4µA when connecting to OUT.
BATT/Damping Switch
AIC1612 is designed with an internal damping switch
(Fig.33) to reduce ringing at LX. The damping
switch supplies a path to quickly dissipate the en-
ergy stored in inductor and reduces the ringing at LX.
Damping LX ringing does not reduce VOUT ripple,
but does reduce EMI. R1=200Ω works well for most
applications while reducing efficiency by only 1%.
Larger R1 value provides less damping, but less im-
pact on efficiency. In principle, lower value of R1 is
needed to fully damp LX when VOUT /VIN ratio is high.
Selecting the Output Voltage
VOUT can be simply set to 3.3V/5.0V by connecting
FB pin to OUT/GND due to the use of internal resis-
tor divider in the IC (Fig.34 and Fig.35). In order to
adjust output voltage, a resistor divider is connected
to VOUT, FB, GND (Fig.36). Vout can be calculated
by the following equation:
R5=R6 [(VOUT / VREF )-1] .....................................(1)
Where VREF =1.23V and VOUT ranging from 1.8V to
5.5V. The recommended R6 is 240KΩ.
Low-Battery Detection
AIC1612 contains an on-chip comparator with 50mV
internal hysteresis (REF, REF+50mV) for low battery
detection. If the voltage at LBI falls below the internal
reference voltage, LBO (an open-drain output) sinks
current to GND.
Component Selection
1. Inductor Selection
An inductor value of 22µH performs well in most
applications. The AIC1612 also works with
inductors in the 10µH to 47µH range. An inductor
with higher peak inductor current tends a higher
output voltage ripple (IPEAK×output filter capaci-
tor ESR). The inductor’s DC resistance signifi-
cantly affects efficiency. We can calculate the
maximum output current as follows:
η
×
−
−= L2
VV
tI
V
V
IINOUT
OFFLIM
OUT
IN
)MAX(OUT
........................................................................(2)
where IOUT(MAX)=maximum output current in
amps
VIN=input voltage
L=inductor value in µH
η=efficiency (typically 0.9)
tOFF=LX switch’ off-time in µS
ILIM=1.0A or 0.65A
2. Capacitor Selection
The output voltage ripple relates with the peak
inductor current and the output capacitor ESR.
Besides output ripple voltage, the output ripple
current also needs to be concerned. A filter ca-
pacitor with low ESR is helpful to the efficiency
and steady state output current of AIC1612.
Therefore NIPPON tantalum capacitor MCM se-
ries with 100µF/6V is recommended. A smaller
capacitor (down to 47µF with higher ESR) is ac-
ceptable for light loads or in applications that can
tolerate higher output ripple.
AIC1612
13
3. PCB Layout and Grounding
Since AIC1612’s switching frequency can range
up to 500kHz, it makes AIC1612 become very
sensitive. So careful printed circuit layout is im-
portant for minimizing ground bounce and noise.
IC’s OUT pin should be as clear as possible.
And the GND pin should be placed close to the
ground plane. Keep the IC’s GND pin and the
ground leads of the input and output filter capaci-
tors less than 0.2in (5mm) apart. In addition,
keep all connection to the FB and LX pins as
short as possible. In particular, when using ex-
ternal feedback resistors, locate them as close
to the FB as possible. To maximize output power
and efficiency and minimize output ripple voltage,
use a ground plane and solder the IC’s GND di-
rectly to the ground plane. Fig.37 to 39 are the
recommended layout diagrams.
Ripple Voltage Reduction
Two or three parallel output capacitors can sig-
nificantly improve output ripple voltage of
AIC1612. The addition of an extra input capaci-
tor results in a stable output voltage. Fig.40
shows the application circuit with the above fea-
tures. Fig. 41 to 48 are the performances of
Fig.40.
APPLICATION EXAMPLES
DAMPING
SWITCH
VIN
VOUT
A
IC1612
OUT
BATT
L
X
GND
Q3
Q2
Q1
L1
R1
200Ω
22µH
VOUT
VIN
R2
100KΩ
AIC1612
C3
C1
L
22µH 47µF
47µF
0.1µF
C2
0.1µF
C4
R1
200Ω
LOW BATTERY
OUTPUT
R4
R3
CLSEL
LX
OUT
FB
GND
REF
LBI
BATT
LBO
SHDN
L: TDK SLF7045T-22OMR90
C1, C3: NIPPON Tantalum Capacitor 6MCM476MB2TER
Fig.33 Simplified Damping Switch Diagram Fig.34 VOUT = 3.3V Application Circuit.
VOUT
VIN
R2
100KΩ
AIC1622
C3
C1
L
22µH 47
µ
F
47µF
0.1µF
C2
0.1µF
C4
R1
200Ω
LOW BATTERY
OUTPUT
R4
R3
CLSEL
L
X
OUT
FB
GND
REF
LBI
BATT
LBO
SHDN
L: TDK SLF7045T-22OMR90
C1, C3: NIPPON Tantalum Capacitor 6MCM476MB2TER
VOUT
VIN
100KΩ
R1
200Ω
R2
22
µ
H 47µF
47µF
0.1µF
0.1µF
LOW BATTERY
OUTPUT
C2
C4
C3
C1
L
AIC1612 R6
R5
R4
R3
SHDN
CLSEL
LX
FB
LBO
GND
REF
LBI
BATT
OUT
L: TDK SLF7045T-22OMR90
C1, C3: NIPPON Tantalum Capacitor 6MCM476MB2TER
VOUT=VREF*(1+R5/R6)
Fig.35 VOUT = 5.0V Application Circuit. Fig.36 An Adjustable Output Application Circuit
AIC1612
14
Fig.37 Top layer Fig.38 Bottom layer Fig.39 Placement
FB
1
LBI
2
LBO
3
CLSEL
4
REF
5 SHDN 6
BATT 7
GND 8
L
X
9
OUT 10
AIC1612
R1
200
R5
R2 100K
R4
R6
R3
C3
0.1µF
C4
1µF
+C5
6V/100µF
+C1
6V/100
µ
F
L1
22
µ
H
JU3
JU2
VOUT
VIN
VOUT
VIN
VIN
VOUT
VIN
D1 is Optional
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)
Connect to OUT for 1.0A limit
Connect to GND for 0.8A limit Connect to GND for shutdown
Connect to VOUT for normal
JU1
+ C2
6V/100uF
+ C6
6V/100µF
+
C7
6V/100
µ
F
L1: TDK SLF7045T-22OMR90
C1~C2, C5~7: NIPPON Tantalum Capacitor 6MCM107MCTER
Fig.40 AIC1612 application circuit with small ripple voltage
Fig. 41 Efficiency (ref. to Fig.40)
Efficiency (%)
Output Current (mA)
0.01 0.1 1 10 100 1000
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
VOUT=5.0V
L=22µH
VIN=1.2V
VIN=2.4V
VIN=3.6V
CLSEL=OUT (ILIMIT =1A)
Fig. 42 Ripple Voltage (ref. to Fig.40)
Ripple Voltage (mV)
Output Current (mA)
0100 200 300 400 500 600 700
0
10
20
30
40
50
60
VOUT=5.0V
L=22µH
VIN=2.4V
VIN=3.6V
VIN=1.2V
CLSEL=OUT (ILIMIT =1A)
AIC1612
15
Fig. 43 Efficiency (ref. to Fig.40)
Efficiency (%)
Output Current (mA)
60
0.01 0.1 1 10 100 1000
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
VOUT=5.0V
L=22µH
VIN=2.4V
VIN=3.6V
VIN=1.2V
CLSEL=GND (ILIMIT =0.65A)
Fig. 44 Ripple Voltage (ref. to Fig.40)
Ripple Voltage (mV)
Output Current (mA)
0100 200 300 400 500
0
10
20
30
40
50
60
VOUT=5.0V
L=22µH
VIN=2.4V
VIN=3.6V
VIN=1.2V
CLSEL=GND (ILIMIT =0.65A)
Fig. 45 Efficiency (ref. to Fig.40)
Efficiency (%)
Output Current (mA)
0.01 0.1 1 10 100 1000
40
45
50
55
60
65
70
75
80
85
90
95
100
VIN=2.4V
VIN=1.2V
VOUT=3.3V
L=22µH
CLSEL=OUT (ILIMIT =1A)
Fig. 46 Ripple Voltage (ref. to Fig.40)
Ripple Voltage (mV)
Output Current (mA)
050 100 150 200 250 300 350 400 450 500 550 600
0
5
10
15
20
25
30
35
40
45
50
VIN=2.4V
VIN=1.2V VOUT=3.3V
L=22µH
CLSEL=OUT (ILIMIT =1A)
Fig. 47 Efficiency (ref. to Fig.40)
Efficiency (%)
Output Current (mA)
0.01 0.1 1 10 100 1000
40
45
50
55
60
65
70
75
80
85
90
95
100
VOUT=3.3V
L=22µH
VIN=2.4V
VIN=1.2V
CLSEL=GND (ILIMIT =0.65A)
Fig. 48 Ripple Voltage (ref. to Fig.40)
Ripple Voltage (mV)
Output Current (mA)
050 100 150 200 250 300 350 400
0
5
10
15
20
25
30
35
VOUT=3.3V
L=22µH
VIN=2.4V
VIN=1.2V
CLSEL=GND (ILIMIT =0.65A)
AIC1612
16
PHYSICAL DIMENSION
10 LEAD MSOP (unit: mm)
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 0.50
L 0.40 0.66
D
E
e
E1
b
A2
A1
C
L
Note:
Information provided by AIC is believed to be accurate and reliable. However, we cannot assume responsibility for
use of any circuitry other than circuitry entirely embodied in an AIC product; nor for any infringement of patents or
other rights of third parties that may result from its use. We reserve the right to change the circuitry and specifica-
tions without notice.
Life Support Policy: AIC does not authorize any AIC product for use in life support devices and/or systems. Life sup-
port devices or systems are devices or systems which, (I) are intended for surgical implant into the body or (ii) sup-
port or sustain life, and whose failure to perform, when properly used in accordance with instructions for use pro-
vided in the labeling, can be reasonably expected to result in a significant injury to the user.
