Datasheet

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Datasheet
AS1302
5V/30mA Adaptive Inductorless Boost Converter
1 General Description
2 Key Features
!
Up to 90% Efficiency
!
2.9V to 5.15V Input Voltage
!
Regulated 5V Output
!
Automatic Mode Switching
!
<1µA Shutdown Current
The AS1302 runs on a 1.2MHz fixed frequency and is
utilized with a low noise regulation scheme to allow
usage together with sensitive RF circuitry from the same
battery supply. Additionally to increase efficiency the
AS1302 switches to 49kHz at light loads.
!
Startup with Full Load (within 1ms)
!
Up to 30mA Load Current
!
Short Circuit Protection
!
Output Disconnected During Shutdown
Designed to reside in portable and space limited
equipment the 1.2MHz charge pump converts a 2.9V to
5.15V input to regulated 5V output with 3% accuracy.
!
Soft-Start
!
No Inductor Required
!
Small External Components Required
(COUT =2.2µF, CFLY =220nF)
!
Low Noise Fixed Frequency (1.2MHz, 49kHz)
Charge Pump:
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The AS1302 is a 30mA inductorless boost converter
using a double H-bridge charge-pump topology with two
external flying capacitors. The AS1302 charge pump
features 1:2 and 2:3 operation modes as well as a 1:1
operation mode where the input is directly connected to
the output.
The shutdown function reduces the supply current to
<1µA and disconnects the load from the output. The
integrated soft-start circuitry prevents high inrush
currents being drawn from the battery during start-up.
The AS1302 includes built-in under-voltage lockout,
short circuit-, and thermal protection circuitry.
The AS1302 is available in TDFN (3x3x0.8mm) 10-pin
and an extremely small 1.2x1.2mm WL-CSP 8-bumps
package with 0.4mm pitch.
!
- 1:1 Battery Feed Through Mode
- 2:3 Single Phase Mode
- 1:2 Single Phase Mode
Package Options:
- TDFN (3x3x0.8mm) 10-pin
- WL-CSP 8-bumps with 0.4mm Pitch
3 Applications
ca
The device is ideal for two or three AA cells or a single
Li-Ion battery cell to 5V conversion, mobile phones,
portable instruments, microprocessor based systems
and remote data-acquisition systems.
ch
ni
Figure 1. AS1302 - Typical Application Diagram
Te
VBATT
2.9V to 5.15V
CFLY1
220nF
C1+
C1-
VBATT
CBAT
2.2µF
On
Off
VOUT
VOUT = 5V
COUT
2.2µF
AS1302
EN
GND
C2+
C2220nF
CFLY2
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Revision 1.03
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AS1302
Datasheet - P i n A s s i g n m e n t s
4 Pin Assignments
GND 1
10 EN
C1- 2
GND
EN
A1
A2
A3
9 VBATT
AS1302
NC 3
C1+ 4
C1+
8 C27 NC
6 C2+
B3
C2
C3
VOUT C2+ C2WL-CSP 8-bumps
VBATT
lv
VOUT 5
B1
C1
GND
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TDFN (3x3x0.8mm) 10-pin
Pin Descriptions
C1-
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Figure 2. Pin Assignments (Through View)
Table 1. Pin Descriptions
Pin Name
C1GND
EN
C1+
VBATT
VOUT
A3
B1
B3
C1
C2
C3
Description
Connector 1-. Negative terminal of flying cap 1.
Ground.
Enable. (operating if EN = 1). Set this digital input to logic high for normal
operation. For shutdown, set to logic low.
Connector 1+. Positive terminal of flying cap 1.
+2.9V to 5.15V Input Voltage. Bypass this pin to GND with a ≥2.2µF low
ESR ceramic capacitor.
+5V Output Voltage. This pin must be bypassed with a ≥2.2µF low ESR
ceramic capacitor.
Connector 2+. Positive terminal of flying cap 2.
Connector 2-. Negative terminal of flying cap 2.
Te
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C2+
C2-
Pin Number
A1
A2
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Revision 1.03
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AS1302
Datasheet - A b s o l u t e M a x i m u m R a t i n g s
5 Absolute Maximum Ratings
Stresses beyond those listed in Table 2 may cause permanent damage to the device. These are stress ratings only,
and functional operation of the device at these or any other conditions beyond those indicated in Section 6 Electrical
Characteristics on page 4 is not implied. Exposure to absolute maximum rating conditions for extended periods may
affect device reliability.
Min
Max
Units
All pins to GND
-0.3
+7.0
V
Operating Temperature Range
-40
+85
ºC
Storage Temperature Range
-65
+125
ºC
2
kV
HBM MIL-Std. 883E 3015.7 methods
500
V
CDM JESD22-C101C methods
The reflow peak soldering temperature
(body temperature) specified is in
accordance with IPC/JEDEC J-STD020D “Moisture/Reflow Sensitivity
Classification for Non-Hermetic Solid
State Surface Mount Devices”.
The lead finish for Pb-free leaded
packages is matte tin (100% Sn).
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ESD
Notes
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Parameter
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Table 2. Absolute Maximum Ratings
+260
ºC
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Package Body Temperature
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Revision 1.03
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AS1302
Datasheet - E l e c t r i c a l C h a r a c t e r i s t i c s
6 Electrical Characteristics
VBATT = 2.9V to 5.15V, VOUT = 5V, COUT = CBAT = 2.2µF, CFLY1 = CFLY2 =220nF, TAMB = -40 to +85ºC. Typical values
are at TAMB = +25ºC and VIN = 3.3V, unless otherwise specified.
Table 3. Electrical Characteristics
Conditions
VBATT(on) Undervoltage Lockout
Rising VBATT
VBATT(off) Undervoltage Lockout
Falling VBATT
VBATT
Battery Supply Voltage
VOUT
Output Voltage Accurracy
IOUT = 0mA, 15mA
VBATT = 5.4V, IOUT = 10~30mA
ΔVO/ΔIO23 Load Regulation in 2:3 Mode
VBATT = 4.3V, IOUT = 10~30mA
ΔVO/ΔIO12 Load Regulation in 1:2 Mode
VBATT = 3.3V, IOUT = 10~30mA
Iinr
Ishort
Mode Switching Voltage
Load Current
2.8
V
5.15
V
5.15
V
2.5
5.0
3
mV/mA
3
5.1
2:3 / 1:2 mode, falling VBATT
3.6
Mode switching voltage hysteresis
150
30
V
mV
mA
VBATT = 3.6V, IOUT = 30mA
22
mVPP
VBATT = 3.6V, IOUT = 2mA
40
mVPP
150
mA
Short-Circuit Current
150
mA
Shutdown Current
Input Levels
1:2 mode, VBATT = 2.9V,
IOUT = 30mA
85
%
2:3 mode, VBATT = 3.8V,
IOUT = 30mA
85
%
VBATT = 3.4V (1:2 mode without load)
240
300
VBATT = 4.5V (2:3 mode without load)
170
230
VBATT = 5.3V (1:1 mode without load)
100
150
EN = 0V
0.01
1
µA
1.1
5.5
V
0.0
0.4
V
ca
Operating Quiescent Current
IOP11
Input High Level
VIL
Input Low Level
ch
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VIH
Oscillator Frequency
pin EN
µA
VBATT = 3.6V, IOUT = 30mA
0.9
1.2
1.5
MHz
VBATT = 3.6V, IOUT = 2mA
40
49
65
kHz
0.5
1
ms
Startup Time
Te
tSTART
V
2
IOP12
fOSC
2.9
Inrush Current
η23
Timing
2.8
1
Efficiency in Switching Mode
IOFF
Units
2
Output Voltage Ripple
η12
IOP23
Max
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Vripple
4.85
1:1 / 2:3 mode, falling VBATT
Vtgr11/23
IOUT
2.4
Typ
2.9
ΔVO/ΔIO11 Load Regulation in 1:1 Mode
Vtgr23/12
Min
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Parameter
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Symbol
Thermal Regulation
TOFF
Temperature Shutdown
Temperature rising
145
Hysteresis
10
ºC
1. The device is tested in a proprietary test mode.
2. The inrush current is limited by the internal soft-start circuitry.
Note: All limits are guaranteed. The parameters with min and max values are guaranteed with production tests or
SQC (Statistical Quality Control) methods.
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Revision 1.03
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AS1302
Datasheet - Ty p i c a l O p e r a t i n g C h a r a c t e r i s t i c s
7 Typical Operating Characteristics
VBATT = 3.3V, VOUT = 5V, COUT = CBAT = 2.2µF, CFLY1 = CFLY2 =220nF, TAMB = +25ºC, unless otherwise specified.
90
90
80
80
70
70
50
1:2
mode
40
2:3
mode
1:1
mode
60
50
30
30
20
20
10
1:2
mode
40
2:3
mode
10
0
0
2.6
3
3.4
3.8
4.2
4.6
5
5.4
2.6
3
3.4
Input Voltage (V)
100
4.2
4.6
5
5.4
Figure 6. Efficiency vs. Input Voltage; ILOAD = 30mA
100
90
90
80
70
60
50
1:2
mode
40
2:3
mode
30
1:1
mode
Efficiency (%)
80
Efficiency (%)
3.8
Input Voltage (V)
Figure 5. Efficiency vs. Input Voltage; ILOAD = 20mA
70
60
50
1:2
mode
40
2:3
mode
1:1
mode
30
20
20
10
0
2.6
3
ca
10
3.4
3.8
4.2
4.6
5
0
5.4
2.6
3
3.4
Input Voltage (V)
4.6
5
5.4
300
Vi n=3.4V (1:2 Mode)
275
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275
4.2
Figure 8. Quiescent Current vs. Temperature
ni
300
3.8
Input Voltage (V)
Figure 7. Quiescent Current vs. Input Voltage
Quiescent Current (µA)
250
225
200
Te
Quiescent Current (µA)
1:1
mode
lv
60
Efficiency (%)
100
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Figure 4. Efficiency vs. Input Voltage; ILOAD = 10mA
100
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Efficiency (%)
Figure 3. Efficiency vs. Input Voltage; ILOAD = 1mA
175
150
125
100
75
250
Vi n=4.5V (2:3 Mode)
Vi n=5.3V (1:1 Mode)
225
200
175
150
125
100
75
50
2.4
2.9
3.4
3.9
4.4
4.9
5.4
50
-45 -30 -15
Input Voltage (V)
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0
15
30
45
60
75
90
Temperature (°C)
Revision 1.03
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AS1302
Datasheet - Ty p i c a l O p e r a t i n g C h a r a c t e r i s t i c s
Figure 10. Efficiency vs. Output Current; VBATT = 3.3V
100
100
90
90
80
80
70
70
50
40
60
49kHz
40
30
30
20
20
10
10
0
0
0.1
1
10
100
0.1
Figure 11. Efficiency vs. Output Current; VBATT = 3.6V
100
Figure 12. Efficiency vs. Output Current; VBATT = 4V
90
80
70
60
Efficiency (%)
80
Efficiency (%)
10
100
90
49kHz 1.2MHz
50
40
30
70
60
49kHz 1.2MHz
50
40
30
20
20
10
10
0
0
0.1
1
10
100
0.1
Figure 13. Efficiency vs. Output Current; VBATT = 4.3V
90
90
80
Efficiency (%)
70
60
100
100
ch
80
10
Figure 14. Efficiency vs. Output Current; VBATT = 5.4V
ni
100
1
Output Current (mA)
ca
Output Current (mA)
49kHz 1.2MHz
50
Te
Efficiency (%)
1
Output Current (mA)
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Output Current (mA)
100
1.2MHz
50
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49kHz 1.2MHz
lv
60
Efficiency (%)
Efficiency (%)
Figure 9. Efficiency vs. Output Current; VBATT = 2.9V
40
60
50
40
30
30
20
20
10
10
0
permanent 1:1 Mode
70
0
0.1
1
10
100
0.1
Output Current (mA)
www.austriamicrosystems.com/DC-DC_Step-Up/AS1302
1
10
100
Output Current (mA)
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AS1302
Datasheet - Ty p i c a l O p e r a t i n g C h a r a c t e r i s t i c s
Figure 15. Output Voltage vs. Output Current
Figure 16. Output Voltage vs. Output Current
5.15
5.15
5.1
1.2MHz
5.05
5
4.95
5.05
5
4.95
4.9
Vi n = 2.9V
Vi n = 3.0V
Vi n = 3.3V
Vi n = 3.6V
Vi n = 4.3V
4.85
0.01
0.1
Vi n = 4.0V
1
10
4.85
0.01
100
0.1
Figure 17. Output Voltage vs. Input Voltage
10
100
Figure 18. Output Voltage vs. Temperature
5.15
1:2
mode
2:3
mode
5.1
1:1
mode
5.05
5
4.95
Iout = 4mA
4.9
Output Voltage (V)
5.1
Output Voltage (V)
1
Output Current (mA)
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Output Current (mA)
5.15
1.2MHz
lv
4.9
49kHz
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49kHz
Output Voltage (V)
Output Voltage (V)
5.1
5.05
5
4.95
4.9
Iout = 10mA
Iout = 0.1mA
Iout = 10mA
Iout = 20mA
Iout = 30mA
Iout = 30mA
4.85
2.9
3.2
3.5
3.8
4.1
4.4
4.7
5
5.3
4.85
-45 -30 -15
0
15
30
45
60
75
90
Temperature (°C)
ca
Input Voltage (V)
1
0.875
0.625
0.5
Te
Startup Time (ms)
ch
0.75
ni
Figure 19. Startup Time vs. Input Voltage; load=166Ω
0.375
0.25
0.125
0
2.9 3.15 3.4 3.65 3.9 4.15 4.4 4.65 4.9
Input Voltage (V)
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Revision 1.03
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AS1302
Datasheet - Ty p i c a l O p e r a t i n g C h a r a c t e r i s t i c s
50mA/Div
Figure 21. Inrush Current; no load
2V/Div
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2V/Div
50µs/Div
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200µs/Div
Figure 22. Switching Frequency vs. Input Voltage;
IOUT = 2mA
Figure 23. Switching Frequency vs. Input Voltage;
IOUT = 20mA
1.5
Switching Frequency (MHz)
Switching Frequency (kHz)
65
60
55
50
45
40
1.4
1.3
1.2
1.1
1
0.9
2.9
3.2
3.5
3.8
4.1
4.4
4.7
5
2.9
3.2
Switching Frequency (MHz)
ch
Switching Frequency (kHz)
Te
50
45
0
15
30
45
4.1
4.4
4.7
5
1.5
55
40
-45 -30 -15
3.8
Figure 25. Switching Frequency vs. Temperature;
IOUT = 20mA
ni
Figure 24. Switching Frequency vs. Temperature;
IOUT = 2mA
60
3.5
Input Voltage (V)
ca
Input Voltage (V)
65
lv
EN
EN
1V/Div
VOUT
VOUT
2V/Div
Iinr
Figure 20. Turn-ON / Turn-OFF Time @ load = 166Ω
60
75
90
1.4
1.3
1.2
1.1
1
0.9
-45 -30 -15
Temperature (°C)
www.austriamicrosystems.com/DC-DC_Step-Up/AS1302
0
15
30
45
60
75
90
Temperature (°C)
Revision 1.03
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AS1302
Datasheet - Ty p i c a l O p e r a t i n g C h a r a c t e r i s t i c s
500µs/Div
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500µs/Div
lv
50mV/Div
10mA
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IOUT
VOUT
Figure 29. Load Transient; Mode = 1:2,
IOUT = 20 to 4 to 20 mA
20mV/Div - BW=20MHZ
VOUT
1V/Div
VOUT
C2-
3.8V 4.8V
Figure 31. Output Ripple
5mV/Div
Te
VIN
ch
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Figure 30. Line Transient
5ms/Div
www.austriamicrosystems.com/DC-DC_Step-Up/AS1302
50mV/Div
500µs/Div
ca
500µs/Div
4mA
IOUT
VOUT
VOUT
50mV/Div
10mA
IOUT
30mA
Figure 28. Load Transient; Mode = 1:2,
IOUT = 30 to 10 to 30 mA
20mA
VOUT
50mV/Div
10mA
IOUT
30mA
Figure 27. Load Transient; Mode = 2:3,
IOUT = 30 to 10 to 30 mA
30mA
Figure 26. Load Transient; Mode = 1:1,
IOUT = 30 to 10 to 30 mA
10µs/Div
Revision 1.03
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AS1302
Datasheet - D e t a i l e d D e s c r i p t i o n
8 Detailed Description
Functional Description
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The AS1302 is a high efficiency and low noise switched capacitor DC-DC converter that is capable of boost operation.
It is equipped with two built-in coupled H-bridge type switch configurations. Based on the value of the output voltage
the system automatically initiates mode-switching to achieve the highest possible efficiency. The regulation of the
output voltage is achieved by a regulation loop, which modulates the current drive capability of the power transistors so
that the amount of charge transferred from the input to the output at each clock cycle is controlled and is equal to the
charge needed by the load.
Regulation Loop
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The AS1302 operates at a constant frequency. For the regulation loop power transistors, a resistor divider and an error
amplifier are used to keep the output voltage within the allowed limits. The error amplifier takes the feedback and
reference signals as inputs and generates the error voltage signal. The error voltage controls a driver that triggers the
gate voltage of the power transistor which modulates the current drive capability of the power amplifier. The modulated
transistor controls the charge transferred from the input to the output and therefore the regulation of the output is
realized. This regulation concept which is based on adjusting the amount of charge transferred, delivers the smallest
voltage ripple possible.
Figure 32. AS1302 - Functional Block Diagram
CFLY1
C1+
VBATT
+
CBAT
C1-
CFLY2
C2+
C2-
VOUT
Double-H Bridge
Topology
COUT
∫ i ( t ) dt
Vctrl
Vmode
Softstart
ca
Mode
Select
Ref
POR
State Machine
&
Control Logic
Temp
Bias
ni
EN
AS1302
GND
Te
ch
On
Off
CLK
Light/Heavy Load Monitor
To detetect the output current in the 2:3 and in the 1:2 mode, a current sense is used. The device switches to a lower
switching frequency (49kHz typ), due to a detected light-load condition. With this frequency an excellent light-load
efficiency is achieved and no audible noise is generated. If the load is increasing (typically more than 3mA), the device
operates at 1.2MHz.
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Revision 1.03
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AS1302
Datasheet - D e t a i l e d D e s c r i p t i o n
Switch Configuration
The AS1302 has nine built-in power switches in the shape of two coupled H-bridge topologies. The system features
1:2 and 2:3 operation modes as well as a 1:1 operation where the input is directly connected to the output.
Figure 33. 2:3 Operating Mode
Charging Phase
lv
Pumping Phase
VOUT
+5V
VOUT
+5V
SW1
SW1
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VBATT
+2.9V to 5.15V
al
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In 2:3 operation mode two flying capacitors are placed in series and each capacitor is charged to the half of the input
voltage. In pumping phase the flying capacitors are placed in parallel. The bottom-plates of the parallel flying
capacitors CFLY1 and CFLY2 are connected to the input voltage so that the voltage at the top-plates of the flying
capacitors is boosted to a voltage equal to VBATT + VBATT/2. By connecting the top-plates of the capacitors to the
output, the output voltage in the 2:3 mode can be up to one and a half of VBATT. If the top-plate voltage is higher than
5V, the regulation loop adapts the power transistor’s on-resistance to drop some voltage.
SW2
VBATT
+2.9V to 5.15V
CFLY1
SW2
CFLY1
CFLY2
CFLY2
SW3
SW3
SW4
SW4
In 1:2 operation both flying capacitors are placed in parallel to the input voltage, and therefore charged to the input
voltage. During pumping phase the input voltage is connected to the bottom of the charged flying capacitors. The
voltage at the top-plates of the parallel capacitors is now boosted to 2VBATT. By connecting the top-plates of the
capacitors to the output, the output can be charged to twice the voltage of VBATT. If the top-plate voltage is higher than
5V the regulation loop limits the charge transfer to the output.
Figure 34. 1:2 Operating Mode
ni
ca
Charging Phase
Te
ch
VBATT
+2.9V to 5.15V
Pumping Phase
VOUT
+5V
VOUT
+5V
SW1
SW2
CFLY1
CFLY2
SW1
VBATT
+2.9V to 5.15V
SW2
CFLY1
CFLY2
SW3
SW3
SW4
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SW4
Revision 1.03
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AS1302
Datasheet - D e t a i l e d D e s c r i p t i o n
Soft-start
The soft-start circuit prevents the supply from high inrush currents caused by the converter’s power-up sequence.
During the soft-start (0.5ms typ) the device limits the inrush current. The device is capable to power-up at the minimum
specified battery voltage and with the maximum load (ohmic equivalent) applied to the output.
Undervoltage Lockout, UVLO
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The AS1302 is equipped with an undervoltage lockout functionality. If the battery voltage drops below 2.5V (typ) the
device enters the undervoltage lockout condition. The device remains in this condition until the battery voltage is high
enough to enter the soft start sequence. An internal hysteresis of 300mV prevents ringing during startup. If the input
voltage increases to 2.8V (typ) again after such a condition the device turns-on automatically.
Shutdown Mode
lv
The AS1302 enters low-power shutdown mode when EN is set to logic low. In shutdown the charge-pump action is
halted, the output is completely disconnected from the input and VOUT will drop to 0V.
Note: For a stable operation trigger at least a rising edge on the EN pin to set the internal settings of the device after
VBATT power-up.
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Short-Circuit Protection
Short-circuit protection prevents damage to the device if the output is shorted to ground. Whenever the output voltage
is pulled significantly below VBATT, short-circuit protection is triggered and limits the current. As soon as VOUT recovers
the protection is released and the device enters soft-start mode.
Thermal Shutdown
The AS1302 offers thermal shutdown, which prevents damage due to an over-temperature condition. Thermal
shutdown will be initiated if the junction temperature exceeds 145°C. If the temperature drops below this value, the
thermal shutdown will be released automatically and the device resumes operation. A hysteresis prevents the thermal
shutdown from oscillating.
Efficiency Consideration
In the 2:3 operation mode the input current of the charge pump is approximately 1.5x the load current. In an ideal
charge pump the efficiency can be calculated by:
(EQ 1)
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V OUT
V OUT × I OUT
P OUT
η = ------------- = ------------------------------------------- = ------------------------V BATT × 1, 5I OUT
P IN
1, 5V BATT
V OUT
V OUT × I OUT
P OUT
η = ------------- = ------------------------------------- = ------------------P IN
2V BATT
V BATT × 2I OUT
(EQ 2)
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The same works for the 1:2 operation mode. The input current of the charge pump is approximately 2x the load
current. The efficiency of a charge pump in 1:2 operation mode can be calculated by:
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For typical and high output power conditions the quiescent current and the switching losses are negligible and (EQ 1)
and (EQ 2) are valid. Hence, with the same input Voltage the 2:3 operation mode will result into a higher efficiency than
the 1:2 operation mode.
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Revision 1.03
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AS1302
Datasheet - A p p l i c a t i o n I n f o r m a t i o n
9 Application Information
External Component Selection
The high internal oscillator frequency of 1.2MHz permits the use of small capacitors for both, the flying capacitors and
the output capacitors. For any given load the value of the flying- and output capacitors as well as their ESR are
affecting the output voltage performance.
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In general, the capacitor’s ESR is inversely proportional to its physical size. Larger capacitances and higher voltage
ratings tend to reduce ESR. The ESR is a function of the frequency too, so it must be rated at the devices operating
frequency. Another factor affecting capacitor ESR is temperature.
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Note: Many capacitors have a huge capacity variation over temperature. This can be compensated by choosing a
capacitor with a better thermal coefficient or by choosing a larger nominal value to ensure proper operation
over temperature.
Input Capacitor
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It is not critical which type of input bypass capacitor CBAT and output filter capacitor COUT is used, but it will affect the
performance of the charge pump. Low ESR capacitors should be used to minimize VOUT ripple. Multi-layer ceramic
capacitors are recommended since they have extremely low ESR and are available in small footprints.
A 2.2µF input bypass low ESR capacitor such as tantalum or ceramic is recommended to reduce noise and supply
transients. During startup and mode change it supplies a part of the peak input current drawn by the device.
Output Capacitor
The output capacitor is charged to VOUT during the pumping phase. The ESR of the output capacitor introduces spikes
in the output voltage waveform whenever the charge pump charges COUT. These spikes contribute to the ripple voltage of VOUT. Therefore, ceramic or tantalum low ESR capacitors are recommended for COUT to minimize the output
voltage ripple.
Table 4. Recommended Input and Output Capacitors
Part Number
GRM188R61C225KE15
C
TC Code
Rated Voltage
Dimensions
2.2µF
X5R
16V
0603
2.2µF
X7R
25V
0805
GRM188R60J475KE19
4.7µF
X5R
6.3V
0603
GRM188R60J106ME47
10µF
X5R
6.3V
0603
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GRM21BR71E225KA73
Figure 35. Load Regulation Comparision with different
Capacitors
2.2µF 16V 0603
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5
4.95
4.7µF 6.3V 0603
10µF 6.3V 0603
60
40
20
2.2µF 16V 0603
4.9
2.2µF 25V 0805
1.2MHz
80
Output Ripple (mV)
5.05
49kHz
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Output Voltage (V)
5.1
Figure 36. Output Ripple vs. Output Current
Comparision with different Capacitors
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5.15
Manufacturer
Murata
www.murata.com
2.2µF 25V 0805
4.7µF 6.3V 0603
10µF 6.3V 0603
4.85
0
0
5
10
15
20
25
30
0
Load Current (mA)
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5
10
15
20
25
30
Load Current (mA)
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AS1302
Datasheet - A p p l i c a t i o n I n f o r m a t i o n
Flying Capacitor Selection
To ensure the required output current and avoid high peak currents the values of the flying capacitors CFLY1 and CFLY2
are very critical. A 220nF capacitor is sufficient for most applications. Dependent on the operation mode the AS1302
alternately charges and discharges the CFLY1/2 . While the ESR of the output capacitor produces a part of the output
voltage ripple, the ESR of the flying capacitors directly adds to the charge pump’s output source resistance. Therefore
low ESR capacitors, e.g. tantalum or ceramic, are recommended for the flying capacitors as well.
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Due to different materials for ceramic capacitors the on the material depending temperature and voltage coefficients
have to be considered. The capacitance of a X7R ceramic capacitor is more stable than a Z5U or Y5V ceramic
capacitor over the whole temperature range from -40°C to +85°C. As an additional effect a Z5U or Y5V ceramic
capacitor will loose about the half of his nominal capacitance when the rated voltage is applied.
Table 5. Recommended Flying Capacitors
C
TC Code
Rated Voltage
Dimensions
Manufacturer
Murata
www.murata.com
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Part Number
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It is important to choose the ceramic capacitor according to the minimum available capacitance over the operating
voltage and the bias voltage. This information is stated in the datasheets of the capacitor manufacturer.
GRM188R71E224KA88
220nF
X7R
25V
0603
GRM155R61A224KE19
220nF
X5R
10V
0402
Layout Consideration
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To achieve the best performance of the AS1302 a careful board layout is necessary to reduce the impact of the high
switching frequency and the high transient currents which are produced by the device. For a proper regulation under all
conditions a true ground plane and short connections to all external capacitors are needed.
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AS1302
Datasheet - P a c k a g e D r a w i n g s a n d M a r k i n g s
10 Package Drawings and Markings
The device is available in a TDFN (3x3x0.8mm) 10-pin and WL-CSP 8-bumps package.
Figure 37. TDFN (3x3x0.8mm) 10-pin Package Diagram
D2
SEE
DETAIL B
A
D
D2/2
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2x
E
E2
E2/2
L
aaa C
PIN 1 INDEX AREA
(D/2 xE/2)
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K
PIN 1 INDEX AREA
(D/2 xE/2)
aaa C
N N-1
2x
e
TOP VIEW
e
DETAIL B
(ND-1) X e
b
bbb
C
ddd
C A B
BTM VIEW
Terminal Tip
A3
ccc C
A
C
SIDE VIEW
A1
SEATING
PLANE
0.08 C
Datum A or B
ODD TERMINAL SIDE
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Table 6. TDFN (3x3x0.8mm) 10-pin Package Dimensions
Symbol
Min
Typ
Max
A
0.70
0.75
0.80
A1
0.00
0.02
0.05
A3
0.20 REF
L1
0.03
0.15
L2
0.13
aaa
0.15
bbb
0.10
ccc
0.10
ddd
0.05
eee
0.08
ggg
0.10
Symbol
D BSC
E BSC
D2
E2
L
θ
k
b
e
N
ND
Min
2.20
1.40
0.30
0º
0.20
0.18
Typ
3.00
3.00
0.40
0.25
0.50
10
5
Max
2.70
1.75
0.50
0.30
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Note:
1.
2.
3.
4.
Figure 37 is shown for illustration only.
N is the total number of terminals.
All dimensions are in millimeters, angle is in degrees.
Dimensioning and tolerancing conform to ASME Y14.5M-1994.
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Revision 1.03
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AS1302
Datasheet - P a c k a g e D r a w i n g s a n d M a r k i n g s
Figure 38. WL-CSP 8-bumps Package Diagram
Bottom view
Ball side
Top through view
205±20
CCC
20µm
270
±10
400
1210±20.00
200 typ.
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40 typ.
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20
350 typ.
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205±20
1210±20.00
600±30
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Notes:
ccc Coplanarity
All dimensions in µm
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AS1302
Datasheet - O r d e r i n g I n f o r m a t i o n
11 Ordering Information
The device is available as the standard products shown in Table 7.
Table 7. Ordering Information
Marking
AS1302-BWLT
ASQ7
AS1302-BTDT
ASQ7
Description
5V/30mA Adaptive Inductorless Boost
Converter
5V/30mA Adaptive Inductorless Boost
Converter
Delivery Form
Package
Tape and Reel
WL-CSP 8-bumps
Tape and Reel
TDFN (3x3x0.8mm)
10-pin
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Ordering Code
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Note: All products are RoHS compliant and Pb-free.
Buy our products or get free samples online at ICdirect: http://www.austriamicrosystems.com/ICdirect
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For further information and requests, please contact us mailto:[email protected]
or find your local distributor at http://www.austriamicrosystems.com/distributor
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AS1302
Datasheet
Copyrights
Copyright © 1997-2010, austriamicrosystems AG, Tobelbaderstrasse 30, 8141 Unterpremstaetten, Austria-Europe.
Trademarks Registered ®. All rights reserved. The material herein may not be reproduced, adapted, merged,
translated, stored, or used without the prior written consent of the copyright owner.
All products and companies mentioned are trademarks or registered trademarks of their respective companies.
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Disclaimer
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Devices sold by austriamicrosystems AG are covered by the warranty and patent indemnification provisions appearing
in its Term of Sale. austriamicrosystems AG makes no warranty, express, statutory, implied, or by description regarding
the information set forth herein or regarding the freedom of the described devices from patent infringement.
austriamicrosystems AG reserves the right to change specifications and prices at any time and without notice.
Therefore, prior to designing this product into a system, it is necessary to check with austriamicrosystems AG for
current information. This product is intended for use in normal commercial applications. Applications requiring
extended temperature range, unusual environmental requirements, or high reliability applications, such as military,
medical life-support or life-sustaining equipment are specifically not recommended without additional processing by
austriamicrosystems AG for each application. For shipments of less than 100 parts the manufacturing flow might show
deviations from the standard production flow, such as test flow or test location.
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The information furnished here by austriamicrosystems AG is believed to be correct and accurate. However,
austriamicrosystems AG shall not be liable to recipient or any third party for any damages, including but not limited to
personal injury, property damage, loss of profits, loss of use, interruption of business or indirect, special, incidental or
consequential damages, of any kind, in connection with or arising out of the furnishing, performance or use of the technical data herein. No obligation or liability to recipient or any third party shall arise or flow out of
austriamicrosystems AG rendering of technical or other services.
Contact Information
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Headquarters
austriamicrosystems AG
Tobelbaderstrasse 30
A-8141 Unterpremstaetten, Austria
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Tel: +43 (0) 3136 500 0
Fax: +43 (0) 3136 525 01
For Sales Offices, Distributors and Representatives, please visit:
http://www.austriamicrosystems.com/contact
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