AIC1612 - Analog Integrations Corporation

AIC1612

High Efficiency Selectable Current Limit

Synchronous Step-Up DC/DC Converter



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. Sim-

ply consuming 20µA of quiescent current, these

devices offer a built-in synchronous rectifier 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 flexibility,

the peak current of internal switch is selectable

(0.65A or 1.0A). AIC1612 also features a circuit

that eliminates noise due to inductor 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 L

X

LBI

+

ON OFF

+

Low Battery

Detection

0.1µF

VIN

22µH

47µF

Selectable Current Limit

(1.0A or 0.65A) CLSEL

200Ω

BATT

Analog Integrations Corporation Si-Soft Research Center DS-1612P-03 010405

3A1, No.1, Li-Hsin Rd. I , Science Park , Hsinchu 300, Taiwan , R.O.C.

TEL: 886-3-5772500 FAX: 886-3-5772510 www.analog.com.tw 1

AIC1612



ORDERING INFORMATION

A

IC1612XXXX PIN CONFIGURATION

TOP VIEW

1

3

4

2

10

8

7

9

FB

LBI

LBO

CLSEL

REF

OUT

LX

GND

BATT

SHDN

56

Example: AIC1612COTR



In MSOP-10 Package & Taping

& Reel Packing Type

AIC1612POTR

 In MSOP-10 Lead Free Package

& Taping & Reel Packing Type

PACKING TYPE

TR: TAPE & REEL

PACKAGING TYPE

O: MSOP-10

C: Commercial

P: Lead Free Commercial



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

SHDN

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

Maximum Junction Temperature 125°C

Storage Temperature Range -65°C ~150°C

Lead Temperature (Soldering 10 Sec.) 260°C

Absolute Maximum Ratings are those values beyond which the life of a device may be impaired.



TEST CIRCUIT

Refer to Typical Application Circuit.

2

AIC1612



ELECTRICAL CHARACTERISTICS (VIN=2.0V, VOUT=3.3V, FB=VOUT, TA=25°C, unless

otherwise specified.) (Note1)

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 (Note2) 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

(Note3) 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

(Note4) 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

%

3

AIC1612



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: Specifications are production tested at TA=25°C. Specifications over the -40°C to 85°C operating tem-

perature range are assured by design, characterization and correlation with Statistical Quality Controls

(SQC).

Note 2: Start-up voltage operation is guaranteed without the addition of an external Schottky diode between the

input and output.

Note 3: Steady-state output current indicates that the device maintains output voltage regulation under load.

Note 4: Device is bootstrapped (power to the IC comes from OUT). This correlates directly with the actual bat-

tery supply.

4

AIC1612



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)

5

AIC1612



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)

6

AIC1612



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

A

IC1610 (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

7

AIC1612



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 Without Damping Ringing Function

8

AIC1612



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

9

AIC1612



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

LBO

+

-

+

-

+

-

+

-

+

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

LBI

CLSEL

SHDN

F/ F

Q

R

S

Q2

Q1

Reference Voltage

Mirror

Maximum On-Time

One Shot

Minimum Off-Time

One Shot

10

AIC1612



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 op-

erates with an input voltage down to 0.7V. Quies-

cent 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 typically 0.3Ω to improve overall effi-

ciency 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 con-

necting to GND to get 5.0V. CLSEL pin of AIC1612

offers a selectable current limit (1.0A or 0.65A). The

lower current limit allows 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 sig-

nificantly improves efficiency without an additional

external 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 regulation (<10mV). A bypass capacitor of

0.1µF is required for proper operation and good

performance.

11

AIC1612

Shutdown Low-Battery Detection

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.

AIC1612 contains an on-chip comparator with 50mV

internal hysteresis (REF, REF+50mV) for low bat-

tery detection. If the voltage at LBI falls below the in-

ternal 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 in-

ductors 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:

Current Limit Select Pin

AIC1612 allows a selectable inductor current limit of

either 1.0A or 0.65A. The flexibility contributes to

designs 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 damp-

ing switch supplies a path to quickly dissipate the

energy stored in inductor and reduces the ringing at

LX. Damping LX ringing does not reduce VOUT rip-

ple, 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 impact on efficiency. In principle, lower value of

R1 is needed to fully damp LX when VOUT /VIN ratio

is high.

η

























×

−

−= L2

VV

tI

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

Selecting the Output Voltage

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.

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.

12

AIC1612

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 ca-

pacitors 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 pow-

power and efficiency and minimize output ripple

voltage, use a ground plane and solder the IC’s

GND directly 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

L

X

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

22

µ

H

L: TDK SLF7045T-22OMR90

C1, C3: NIPPON Tantalum Capacitor 6MCM476MB2TER

VOUT=VREF*(1+R5/R6)

VOUT

VIN

100KΩ

R1

200Ω

R2

47µF

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

Fig.35 VOUT = 5.0V Application Circuit. Fig.36 An Adjustable Output Application Circuit

13

AIC1612



APPLICATION EXAMPLES (Continued)

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

0.1

µ

F

C4

1µF

+C5

6V/100µF

+C1

6V/100

µ

F

L1

22

µ

H

JU3

JU2

VOUT

VIN

VOUT

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)

14

AIC1612



APPLICATION EXAMPLES (Continued)

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)

15

AIC1612

e

θ

L

c

E

E1

D

A2

b

A1

0.50 BSC

0.40

0°

0.70

6°

4.90 BSC

0.13

2.90

0.75

0.15

0.05

0.23

3.10

0.95

0.30

0.15

S

Y

M

B

O

L

A

MSOP-10

MILLIMETERS

MIN.

1.10

MAX.

A2

A

0.25

SECTION A-A

BASE METAL

GAUGE PLANE

WITH PLATING

A1

b

c

D

eA

E1

E

SEE VIEW B

A



PHYSICAL DIMENSION (unit: mm)

 MSOP-10

θ

L

SEATING PLANE

VIEW B

Note: Note:

Information provided by AIC is believed to be accurate and reliable. However, we cannot assume responsibility for use of any cir-

cuitry 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 specifications without notice.

Information provided by AIC is believed to be accurate and reliable. However, we cannot assume responsibility for use of any cir-

cuitry 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 specifications without notice.

Life Support Policy: AIC does not authorize any AIC product for use in life support devices and/or systems. Life support devices or

systems are devices or systems which, (I) are intended for surgical implant into the body or (ii) support or sustain life, and whose

failure to perform, when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected

to result in a significant injury to the user.

Life Support Policy: AIC does not authorize any AIC product for use in life support devices and/or systems. Life support devices or

systems are devices or systems which, (I) are intended for surgical implant into the body or (ii) support or sustain life, and whose

failure to perform, when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected

to result in a significant injury to the user.

16