ETC AIC1641-30CW

AIC1641
LOW VOLTAGE STEP-UP DC/DC CONVERTER
SPEC NO: DS-1641-00 05/04/00
FEATURES
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DESCRIPTION
Guaranteed Start-Up from Below 0.9 V.
High Efficiency.
Low Quiescent Current.
Fixed Output Voltage: 2.7V, 3.0V, 3.3V, and 5V.
Logic Controlled Shutdown.
External Switch Driver for High Power Level Application.
The AIC1641 is a high efficiency step-up DC/DC
converter for applications using 1 to 4 battery cells.
Only three external components are required to deliver a fixed output voltage of 2.7V, 3.0V, 3.3V, or
5.0V.
Pulse Frequency Modulation scheme brings optimized performance for applications with light output
loading and low input voltage. The output ripple
APPLICATIONS
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and noise are lower compared with the circuit op-
Pagers.
Cameras.
Wireless Microphones.
Pocket Organizers.
Battery Backup Suppliers.
Portable Instruments.
erating in PSM mode. The AIC1641 starts up from
below 0.9V input to boost either 2.7V, 3.0V, 3.3V,
or 5.0V output with 1mA load.
Some useful features include, shutdown mode for
saving the life of battery. The PFM control circuit
operates in 100KHz (max.) switching rate, resulting
in smaller passive component size, which makes
the AIC1641 an ideal choice of DC/DC converter
for space conscious applications.
TYPICAL APPLICATION CIRCUIT
VOUT
+
C1
47µF
VOUT
D1
1N5819
L1
VIN
0.9V
EXT
CB
33µH
Q1
CE
GND
AIC1641
10nF
2SD1803
RB
300
One Cell Step-Up DC/DC Converter
ANALOG INTEGRATIONS CORPORATION
www.analog.com.tw
4F, 9 Industry E. 9th Road, Science-based Industrial Park , Hsinchu, Taiwan, R.O.C.
TEL: (8863)577-2500 FAX:(8863)577-2510
1
AIC1641
LOW VOLTAGE STEP-UP DC/DC CONVERTER
SPEC NO: DS-1641-00 05/04/00
ORDERING INFORMATION
AIC1641-XXCX
ORDER NUM BER
PACKAGE TYPE
O: MSOP8
S: SMALL OUTLINE
W : SOT89-5
AIC1641-27CS
AIC1641-30CS
AIC1641-33CS
AIC1641-50CS
(SO8)
OUTPUT VOLTAGE
27: 2.7V
30: 3.0V
33: 3.3V
50: 5.0V
PIN CONFIGURATION
VOUT 1
8 CE
EXT 2
7 NC
6 NC
NC 3
NC 4
AIC1641-27CS
AIC1641-30CS
AIC1641-33CS
AIC1641-50CS
(SO8)
5 GND
VOUT 1
8 CE
EXT 2
7 NC
6 NC
NC 3
NC 4
TOP VIEW
AIC1641-27CW
AIC1641-30CW
AIC1641-33CW
AIC1641-50CW
(SOT89-5)
5 GND
GND
EXT
5
1
NC
4
2
VOUT
3
CE
ABSOLUATE MAXIMUM RATINGS
Supply Voltage
……………………………………………………………………………….12V
CE input Voltage ……………………………………………………………………………….12V
EXT pin Voltage
…………………………………………………………….-0.3V to Vout+0.3V
EXT pin Current
………………………………………………………………………….± 50mA
Power Dissipation
……………………………………………………………………….500mW
Operating Temperature Range ………………………………………………….-40 °C to 85°C
Storage Temperature Range ………………………………………………… -65°C to 150 °C
Lead Temperature (Sordering 10 Sec.)
…………………………………………………260°C
TEST CIRCUIT
AIC1641
VOUT
2.5V
EXT
FOUT
CE
GND
Oscillator Test Circuit
ANALOG INTEGRATIONS CORPORATION
www.analog.com.tw
4F, 9 Industry E. 9th Road, Science-based Industrial Park , Hsinchu, Taiwan, R.O.C.
TEL: (8863)577-2500 FAX:(8863)577-2510
2
AIC1641
LOW VOLTAGE STEP-UP DC/DC CONVERTER
SPEC NO: DS-1641-00 05/04/00
"
ELECTRICAL CHARACTERISTICS
PARAMETER
Output Voltage
(Ta=25°°C, IO=10mA, Unless otherwise specified)
TEST CONDITIONS
SYMBOL
VIN=1.8V
VIN=1.8V
VOUT
VIN=2.0V
VIN=3.0V
Input Voltage
MIN.
TYP.
MAX.
2.633
2.700
2.767
2.925
3.000
3.075
3.218
3.300
3.382
4.875
5.000
5.125
IOUT=1mA, VIN:0→2V
VSTART
Hold-on Voltage
IOUT=1mA, VIN:2→0V
VHOLD
No-Load Input Current
IOUT=0mA
Supply Current 1
EXT at no load, VIN=VOUT x 0.5
0.8
IIN
V
8
V
0.9
V
0.6
V
VIN
Start-Up Voltage
UNIT
µA
18
45
50
Measurement of the IC input current
IDD1
µA
60
80
Supply Current 2
EXT at no load, VIN=VOUT + 0.5
7
EXT “H” On-Resistance
µA
IDD2
Measurement of the IC input current
300
VEXT=VOUT – 0.4V
200
REXTH
Ω
185
130
EXT “L” On-Resistance
110
VEXT= 0.4V
80
REXTL
Ω
70
60
Oscillator Duty Cycle
VIN=VOUT x 0.95
Measure the waveform at the EXT
pin
Max. Oscillator Freq.
65
75
85
%
FOSC
80
105
130
KHz
VIN=VOUT x 0.95
Measure the waveform at the EXT
pin
Chip Enable Pin Input
High Voltage
DUTY
1.2
VIN=VOUT x 0.95
VCEH : 0V→2.5V
Judge the oscillation at EXT pin
1.3
VCEH
1.4
V
2.1
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4F, 9 Industry E. 9th Road, Science-based Industrial Park , Hsinchu, Taiwan, R.O.C.
TEL: (8863)577-2500 FAX:(8863)577-2510
3
AIC1641
LOW VOLTAGE STEP-UP DC/DC CONVERTER
SPEC NO: DS-1641-00 05/04/00
"
ELECTRICAL CHARACTERISTICS
PARAMETER
(Continued)
TEST CONDITIONS
Chip Enable Pin Input
Low Voltage
MIN.
SYMBOL
TYP.
MAX.
UNIT
1.1
VIN=VOUT x 0.95
1.2
VCEL : 2.5V→0V
VCEL
V
1.3
Judge the stop at EXT pin
2.0
CE Pin Input Current
η
Efficiency
"
µA
0.5
Same as IDD1, VCE=VOUT x 0.95
80
%
TYPICAL PERFORMANCE CHARACTERISTICS
Inductor (L1) : 33µH (Pin Type)
Diode
Capacitor (C1) : 47µF (Tantalum Type)
(D1) : 1N5819 Schottky Type
Transistor (Q1) : 2SD1803
AIC1641-27 Loading Regulation (L=33uH)
90
2.75
85
Vin=2.0V
2.65
2.60
Vin=1.5V
Vin=1.8V
Vin=1.2V
2.55
Vin=2.0V
80
Efficiency (%)
2.70
Output Voltage (V)
AIC1641-27 Efficiency (L=33uH)
2.80
75
Vin=1.5V
65
2.50
60
2.45
55
Vin=0.9V
Vin=1.8V
70
Vin=1.2V
Vin=0.9V
50
2.40
0
50
100
150
200
250
300
350
400
450
0
500
50
100
150
AIC1641-30 Load Regulation (L=33uH)
250
300
350
400
450
500
AIC1641-30 Efficiency (L=33uH)
3.1
90
3.0
Vin=2.0V
85
Vin=2.0V
2.9
2.8
Vin=1.2V
2.7
Efficiency (%)
Output Voltage (V)
200
Output Current (mA)
Output Current (mA)
Vin=1.8V
Vin=1.5V
Vin=0.9V
2.6
80
Vin=1.8V
75
70
Vin=1.5V
65
2.5
Vin=0.9V
Vin=1.2V
60
2.4
0
50
100
150
200
250
300
350
400
450
0
50
100
150
200
250
300
350
400
450
Output Current (mA)
Output Current (mA)
ANALOG INTEGRATIONS CORPORATION
www.analog.com.tw
4F, 9 Industry E. 9th Road, Science-based Industrial Park , Hsinchu, Taiwan, R.O.C.
TEL: (8863)577-2500 FAX:(8863)577-2510
4
AIC1641
LOW VOLTAGE STEP-UP DC/DC CONVERTER
SPEC NO: DS-1641-00 05/04/00
"
TYPICAL PERFORMANCE CHARACTERISTICS (CONTINUED)
AIC1641-33 Efficiency (L=33uH)
AIC1641-33 Loading Regulation (L=33uH)
3.6
90
3.4
85
80
Vin=1.5V
3.0
Vin=2.0V
Efficiency (%)
Output Voltage (V)
3.2
2.8
2.6
Vin=0.9V
2.4
75
Vin=2.0V
70
Vin=1.5V
65
Vin=0.9V
60
55
2.2
50
2.0
0
50
100
150
200
250
300
350
0
400
50
100
150
AIC1641-50 Load Regulation (L=33uH)
90
5.0
85
300
350
400
80
Vin=2.0V
4.0
3.5
Vin=3.0V
Efficiency (%)
Output Voltage (V)
250
AIC1641-50 Efficiency (L=33uH)
5.5
4.5
Vin=1.5V
3.0
Vin=1.2V
2.5
100
70
Vin=2.0V
65
Vin=1.5V
Vin=1.2V
Vin=0.9V
55
1.5
0
Vin=3.0V
75
60
Vin=0.9V
2.0
200
300
400
500
600
50
700
0
100
200
Output Current (mA)
2.0
1.8
1.8
1.6
1.6
Input Voltage (V)
1.4
Start up
1.0
0.8
0.6
0.4
400
500
600
700
AIC1641-30 Start-up & Hold-on Voltage (L=33uH)
2.0
1.2
300
Output Current (mA)
AIC1641-27 Start-up & Hold-on Voltage (L=33uH)
Input Voltage (V)
200
Output Current (mA)
Output Current (mA)
1.4
1.2
Start up
1.0
0.8
0.6
Hold on
0.4
Hold on
0.2
0.2
0.0
0
20
40
60
80
100
120
140
160
180
200
0.0
0
20
40
60
Output Current (mA)
80
100
120
140
160
180
200
Output Current (mA)
ANALOG INTEGRATIONS CORPORATION
www.analog.com.tw
4F, 9 Industry E. 9th Road, Science-based Industrial Park , Hsinchu, Taiwan, R.O.C.
TEL: (8863)577-2500 FAX:(8863)577-2510
5
AIC1641
LOW VOLTAGE STEP-UP DC/DC CONVERTER
SPEC NO: DS-1641-00 05/04/00
"
TYPICAL PERFORMANCE CHARACTERISTICS (CONTINUED)
AIC1641-50 Start-up & Hold-on Voltage (L=33uH)
2.0
1.8
1.8
1.6
1.6
1.4
1.4
Input Voltage (V)
Input Voltage (V)
AIC1641-33 Start-up & Hold-on Voltage (L=33uH)
2.0
Start up
1.2
1.0
0.8
0.6
0.4
Start up
1.2
1.0
0.8
0.6
Hold on
0.4
Hold on
0.2
0.2
0.0
0.0
0
20
40
60
80
100
120
140
160
180
200
0
20
40
60
Output Current (mA)
80
100
120
140
160
180
200
Output Current (mA)
AIC1641 Switching Frequency vs Temperature
AIC1641 Output Voltage vs Temperature
135
6.0
130
Switching Frequency (kHz)
5.5
Output Voltage (V)
5.0
4.5
4.0
3.5
3.0
2.5
2.0
-40
125
120
115
110
105
100
95
90
-20
0
20
40
60
80
85
-40
100
-20
0
Temperature ( C)
60
80
100
AIC1641 Supply Current vs Temperature
AIC1641 Maximum Duty Cycle vs Temperature
80
79
75
78
70
Supply Current IDD1 (uA)
Maximum Duty Cycle (%)
40
Temperature ( C)
80
77
76
75
74
73
72
71
70
-40
20
o
o
65
60
55
50
45
40
35
-20
0
20
40
60
80
100
30
-40
-20
0
o
20
40
60
80
100
o
Temperature ( C)
Temperature ( C)
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4F, 9 Industry E. 9th Road, Science-based Industrial Park , Hsinchu, Taiwan, R.O.C.
TEL: (8863)577-2500 FAX:(8863)577-2510
6
AIC1641
LOW VOLTAGE STEP-UP DC/DC CONVERTER
SPEC NO: DS-1641-00 05/04/00
"
TYPICAL PERFORMANCE CHARACTERISTICS (CONTINUED)
AIC1641 EXT "H" On-Resistance
400
120
360
110
320
100
280
Resistance ()
Resistance ()
AIC1641 EXT "L" On-Resistance
130
90
80
70
240
200
160
60
120
50
80
40
-40
-20
0
20
40
60
80
40
-40
100
-20
0
20
40
60
80
100
o
o
Temperature ( C)
Temperature ( C)
BLOCK DIAGRAM
CE
1.25V REF.
VOUT
Chip Enable
1M
-
EXT
+
Enable
GND
OSC, 100KHz
PIN DESCRIPTIONS
NC -
Not Connected.
VOUT - IC supply pin. Connect VOUT to the regulator output.
CE -
Chip enable pin (Active High).
EXT - Push pull driver output for external power
switch.
GND – Ground Terminal. Must be low impedance;
sorder directly to ground plane.
ANALOG INTEGRATIONS CORPORATION
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4F, 9 Industry E. 9th Road, Science-based Industrial Park , Hsinchu, Taiwan, R.O.C.
TEL: (8863)577-2500 FAX:(8863)577-2510
7
AIC1641
LOW VOLTAGE STEP-UP DC/DC CONVERTER
SPEC NO: DS-1641-00 05/04/00
APPLICATION INFORMATION
GENERAL DESCRIPTION
AIC1641 PFM (pluse frequency modulation) control-
mode. Continuous conduction mode means that the
inductor current does not ramp to zero during each
cycle.
ler ICs combine a switch mode regulator, push pull
driver, precision voltage reference, and voltage detector in a single monolithic device. They offer both
VIN
extreme low quescient current, high efficiency, and
IIN
very low gate threshold voltage to ensure start-up
with low battery voltage ( 0.8V typ.). Designed to
ID
IOUT
SW
maximize battery life in protable products, and mini-
VOUT
+
EXT
Isw
Ico
mize switching losses by only switching as needed
service the load.
PFM controllers transfer a discreate amount of energy per cycle and regulate the output voltage by
VEXT
modulating switching frequency with the constant
turn-on time. Switching frequency depends on load,
input voltage, and inductor value, and it can range up
to 100KHz.
IIN
IPK
When the output voltage drops, the error comparator
enable 100kHz oscillator that turns on the MOSFET
around 7.5µs and 2.5µs off time. Turning on the
ISW
MOSFET allows inductor current to ramp up, storing
energy in a magnetic field. When MOSFET turns off
that forces inductor current through diode to the output capacitor and load. As the stored energy is de-
Charge Co.
ID
IOUT
pleted, the current ramp down until the diode turns
off. At this point, inductor may ring due to residual
VSW
TDIS
Discharge Co.
energy and stray capacitance. The output capacitor
stores charge when current flowing through the dit
ode is high, and release it when current is low,
thereby maintaining a steady voltage across the load.
As the load increases, the output capacitor dis-
Discontinuous Conduction Mode
charges faster and the error comparator initiates cycles sooner, increasing the switching frequency. The
maximum duty cycle ensure adequate time for energy tranfer to output during the second half each cycle.
Depending on circuit, PFM controller can operate in
either discontinuous mode or continuous conduction
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4F, 9 Industry E. 9th Road, Science-based Industrial Park , Hsinchu, Taiwan, R.O.C.
TEL: (8863)577-2500 FAX:(8863)577-2510
8
AIC1641
LOW VOLTAGE STEP-UP DC/DC CONVERTER
SPEC NO: DS-1641-00 05/04/00
≅
VEXT
1  VOUT + VD − VIN 


TON  VOUT + VD − VSW 
where Vsw = switch drop and proportion to output
current.
IIN
IPK
INDUCTOR SELECTION
ISW
ID
IOUT
VSW
t
Continuous Conduction Mode
t the boundry between continuous and discontinuous
mode, output current (IOB) is determined by
VIN

 1 VIN
IOB = 
TON(1 − x )

 VOUT + VD  2 L
x = (RON+Rs)TON/L.
TON = Switch ON time
In the discontinuous mode, the switching frequency
(fsw) is
VIN 2 × TON 2
In discontinuous mode operation, at the end of the
switch ON time, peak current and energy in the inductor build according to
VIN 
RON + Rs


IPK = 
TON) 
1 − exp( −
L
 RON + Rs 

≅
Ron= Switch turn on resistance, Rs= Inductor DC resistance
FSW =
Minimum and Maximum input voltage, output voltage and output current must be established before
and incuctor can be selected.
x
 VIN 

≅
(TON)1 − 
L
2




where Vd is the diode drop,
2(L)(VOUT + VD − VIN)(IOUT)
To operate as an efficient energy transfer element,
the inductor must fulfill three requirement. First, the
inductance must be low enough for the inductor to
store adquate energy under the worst case condition
of minimum input voltage and switch ON time. Second, the inductance must also be high enough so
maximum current rating of AIC1641 and inductor are
not exceed at the other worst case cindition of
maximum input voltage and ON time. Lastly, the inductor must have sufficiently low DC resistance so
excessive power is not lost as heat in the windings.
But unfotrunately this is inversely related to physical
size.
(1+ x VIN
TON
L
(simple lossless equation),
where x=(RON+Rs)TON/L
1
L × IPK 2
Power required from the inductor per cycle must be
equal or greater than
PL/fSW = (VOUT + VD − VIN)(IOUT)(
In the continuous mode, the switching frequency is
1
)
fsw
in order for the converter to regulate the output.
fsw=
VIN − VSW
x
1 (VOUT + VD − VIN )
)]
[1 + (
ON
OUT
D
SW
OUT
+
−
+ VD − VSW
2 V
T (V
V V )
When loading is over IOB, PFM controller operates in
continuous mode. Inductor peak current can be derived from
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TEL: (8863)577-2500 FAX:(8863)577-2510
9
AIC1641
LOW VOLTAGE STEP-UP DC/DC CONVERTER
SPEC NO: DS-1641-00 05/04/00
 VOUT + VD − VSW x 
 VIN − VSW 
 x
− IOUT + 
IPK = 
TON1 − 
−
IN
SW
V
V
2
2L




 2
 VOUT + VD − VSW x 
 VIN − VSW 
 x
− IOUT − 
IV = 
TON1 − 
−
IN
SW
L
V
V
2
2




 2
Valley current (Iv) is
Table 1 Indicates resistance and height for each coil.
Inductance ( µH )
Resistance ( Ω )
Rated Current (A)
Hieght
(mm)
47
0.25
0.7
4.5
100
0.50
0.5
47
0.25
0.7
100
0.50
0.5
Hold SMT Type PM75
33
0.11
1.2
5.0
Huan Feng PIN Type V0810
33
40m
2
10.0
Power Inductor Type
Sumida SMT Type CD54
Hold SMT Type PM54
CAPACITOR SELECTION
A poor choice for a output capacitor can result in poor
efficiency and hight output ripple. Ordinary aluminum
electrolytics, while inexpensive may have unacceptably poor ESR and ESL. There are low ESR aluminum
capacitors for switch mode DC-DC converters which
work much better than general porpuse unit. Tantalum
capacitors provide still better performance at more expensive. OS-CON capacitors have extremely low ESR
in a small size. If capacitance is reduced, output ripple
will increase.
Most of the input supply is supplied by the input bypasss capacitor, the capacitor voltage rating should be
at least 1.25 times greather than a maximum input
voltage.
DIODE SELECTION
Speed, forward drop, and leakage current are the
three main consideration in selecting a rectifier diode.
Best performance is obtained with Schottky retifier diode such 1N5819. Motorola makes MBR0530 in surface mount. For lower output power a 1N4148 can be
4.5
used although efficiency and start-up voltage will suffer substantially.
COMPONENT POWER DISSIPATION
Opeating in discontinuous mode, power loss in the
winding resistance of inductor can be approximate
equal to
PD L =
2  TON 
 VOUT + VD 

(Rs )
(POUT )
3 L 
 VOUT 
where POUT=VOUT * IOUT ; Rs=Inductor DC R;
VD = Diode drop.
The power dissipated in a switch loss is
PDsw =
2  TON 
 VOUT + VD − VIN 

(RON)
(POUT )
3 L 
VOUT


The power dissipated in rectifier diode is
 VD 
PDd = 
(POUT )
 VOUT 
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4F, 9 Industry E. 9th Road, Science-based Industrial Park , Hsinchu, Taiwan, R.O.C.
TEL: (8863)577-2500 FAX:(8863)577-2510
10
AIC1641
LOW VOLTAGE STEP-UP DC/DC CONVERTER
SPEC NO: DS-1641-00 05/04/00
PHYSICAL DIMENSIONS
!
MSOP 8 (unit: mm)
D
SYMBOL
MIN
MAX
A
0.76
0.97
A1
--
0.20
B
0.28
0.38
C
0.13
0.23
D
2.90
3.10
E
2.90
3.10
H
E
e
e
A
A1
C
B
!
0.65
H
4.80
5.00
L
0.40
0.66
SYMBOL
MIN
MAX
A
1.35
1.75
A1
0.10
0.25
B
0.33
0.51
C
0.19
0.25
D
4.80
5.00
E
3.80
4.00
L
8 LEAD PLASTIC SO (unit: mm)
D
H
E
e
e
A
A1
C
B
1.27(TYP)
H
5.80
6.20
L
0.40
1.27
L
ANALOG INTEGRATIONS CORPORATION
www.analog.com.tw
4F, 9 Industry E. 9th Road, Science-based Industrial Park , Hsinchu, Taiwan, R.O.C.
TEL: (8863)577-2500 FAX:(8863)577-2510
11
AIC1641
LOW VOLTAGE STEP-UP DC/DC CONVERTER
SPEC NO: DS-1641-00 05/04/00
!
SOT-89-5 (unit: mm)
D
A
b1
C
b
HE
E
LE
b
e1
e
!
SYMBOL
MIN
MAX
A
1.40
1.60
b
0.32
0.52
b1
1.40
1.80
C
0.30
0.50
D
4.40
4.60
E
2.40
2.60
e
300 (TYP)
e1
1.50 (TYP)
HE
4.20
5.00
LE
0.80
---
SOT-89-5 Marking
Part No.
AIC1641-27CW
AIC1641-30CW
AIC1641-33CW
AIC1641-50CW
Marking
BD27
BD30
BD33
BD50
ANALOG INTEGRATIONS CORPORATION
www.analog.com.tw
4F, 9 Industry E. 9th Road, Science-based Industrial Park , Hsinchu, Taiwan, R.O.C.
TEL: (8863)577-2500 FAX:(8863)577-2510
12