AMSCO AS1322B-BTTT

AS1322
D a ta S he e t
L o w Vo l ta g e , M i c r o p o w e r, D C - D C St e p - U p C o n v e r t e r s
1 General Description
2 Key Features
The AS1322A and the AS1322B are synchronous, fixed
frequency, very high-efficiency DC-DC boost converters
capable of supplying 3.3V at 150mA from a single AAsupply. Compact size and minimum external parts
requirements make these devices perfect for modern
portable devices.
High-speed switching frequency (1.2MHz) and internally
compensated PWM current mode design provide highlyreliable DC-DC conversion, especially when driving
white LEDs.
The converters are available as the standard products
listed in Table 1.
!
95% Efficiency
!
Single-Cell Operation
!
Delivers 160mA @ 3.3V (from Single AA Cell)
!
Delivers 220mA @ 5.0V (from Two AA Cells)
!
Delivers 570mA @ 3.3V (from Two AA Cells)
!
Low Start-Up Voltage: 0.85V
!
High-Speed Fixed-Frequency: 1.2MHz
!
Internal PMOS Synchronous Rectifier
!
Automatic Powersave Operation (AS1322A)
Table 1. Standard Products
Model
Light Load Switching
AS1322A
Automatic Powersave Operation
!
Continuous Switching at Light Loads (AS1322B)
AS1322B
Continuous Switching
!
Anti-Ringing Control Minimizes EMI
!
Logic Controlled Shutdown (< 1µA)
!
Output Range: 2.5 to 5.0V
!
6-pin TSOT-23 Package
The devices contain two internal MOSFET switches:
one NMOS switch and one PMOS synchronous rectifier.
Anti-ringing control circuitry reduces EMI by damping
the inductor in discontinuous mode, and the devices
exhibit extremely low quiescent current (< 1µA) in shutdown.
In shutdown mode the battery is connected to the output
and VOUT is held at approximately VIN - 0.6V.
The AS1322 is available in a 6-pin TSOT-23 package.
3 Applications
The AS1322 is ideal for low-power applications where
ultra-small size is critical as in medical diagnostic equipment, hand-held instruments, pagers, digital cameras,
remote wireless transmitters, MP3 players, LCD bias
supplies, cordless phones, GPS receivers, and PC
cards.
Figure 1. Typical Application Diagram – Single Cell to 3.3V Synchronous Boost Converter
L1
4.7µH
1
SW
5
6
AA Battery
C1
10µF
On
Off
VIN
VOUT
R1
1.02MΩ
1%
AS1322
4
3
SHDNN
FB
2 GND
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C2
10µF
VOUT
3.3V
160mA
Revision 1.07
R2
604kΩ
1%
1 - 17
AS1322
Data Sheet
- Pin Assignments
4 Pin Assignments
Figure 2. Pin Assignments (Top View)
SW 1
GND 2
6 VIN
AS1322
FB 3
5 VOUT
4 SHDNN
Pin Descriptions
Table 2. Pin Descriptions
Pin
Name
Pin
Number
SW
1
GND
2
FB
3
SHDNN
4
VOUT
5
VIN
6
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Description
Switch Pin. Connect an inductor between this pin and VIN. Keep the PCB
trace lengths as short and wide as is practical to reduce EMI and voltage
overshoot. If the inductor current falls to zero, or pin SHDNN is low, an
internal 100Ω anti-ringing switch is connected from this pin to VIN to
minimize EMI.
Note: An optional Schottky diode can be connected between this pin and
VOUT.
Signal and Power Ground. Provide a short, direct PCB path between this
pin and the negative side of the output capacitor(s).
Feedback Pin. Feedback input to the gm error amplifier. Connect a resistor
divider tap to this pin. The output voltage can be adjusted from 2.5 to 5V by:
VOUT = 1.23V[1 + (R1/R2)]
Shutdown Pin. Logic controlled shutdown input.
1 = Normal operation, 1.2MHz typical operating frequency.
0 = Shutdown; quiescent current <1µA. If SHDNN is undefined, pin SW may
ring.
Note: In a typical application, SHDNN should be connected to VIN through a
1MΩ pull-up resistor.
Output Voltage Sense Input and Drain of the Internal PMOS
Synchronous Rectifier. Bias is derived from VOUT when VOUT exceeds VIN.
PCB trace length from VOUT to the output filter capacitor(s) should be as
short and wide as is practical. VOUT is held at approximately VIN - 0.6V
during shutdown.
Input Voltage. The AS1322 gets its start-up bias from VIN unless VOUT
exceeds VIN, in which case the bias is derived from VOUT. Thus, once
started, operation is completely independent from VIN. Operation is only
limited by the output power level and the internal series resistance of the
supply.
Revision 1.07
2 - 17
AS1322
Data Sheet
- Absolute Maximum Ratings
5 Absolute Maximum Ratings
Stresses beyond those listed in Table 3 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.
Table 3. Absolute Maximum Ratings
Parameter
Min
Max
Units
VIN to GND
-0.3
7
V
SHDNN, SW to GND
-0.3
7
V
FB to GND
-0.3
5
V
VOUT
-0.3
7
V
Operating Temperature Range
-40
+85
ºC
Storage Temperature Range
-65
+125
ºC
Package Body Temperature
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+260
Revision 1.07
ºC
Notes
The reflow peak soldering temperature
(body temperature) specified is in
accordance with IPC/JEDEC J-STD020C “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).
3 - 17
AS1322
Data Sheet
- Electrical Characteristics
6 Electrical Characteristics
TAMB = -40 to +85ºC, VIN = +1.2V, VOUT = +3.3, VSHDNN = +1.2V (unless otherwise specified). Typ values @ TAMB = +25ºC.
Table 4. Electrical Characteristics
Symbol
Parameter
Conditions
Min
Minimum Start-Up Voltage
ILOAD = 1mA
1
Typ
Max
Units
0.85
1
V
0.65
0.85
V
5
V
1.268
V
Minimum Operating Voltage
SHDNN = VIN
Output Voltage Adjust Range
TAMB = 25ºC
2.5
VFB
Feedback Voltage
TAMB = TMIN to TMAX
1.192
IFB
Feedback Input Current
IQPWS
Quiescent Current
(Powersave Operation)
VFB = 1.4V , AS1322A only
30
50
µA
IQSHDNN
Quiescent Current (Shutdown)
VSHDNN = 0V
0.01
1
µA
VFB = 1.25V
2
1.23
1
3
3
nA
IQ
Quiescent Current (Active)
VFB = 1.4V , AS1322B only
150
300
µA
INMOSSWL
NMOS Switch Leakage
VSW = 5V
0.1
5
µA
IPMOSSWL
PMOS Switch Leakage
VSW = 0V
0.1
5
µA
RONNMOS
NMOS Switch On Resistance
VOUT = 3.3V
0.35
0.8
VOUT = 5V
0.20
0.7
RONPMOS
PMOS Switch On Resistance
VOUT = 3.3V
0.45
0.8
VOUT = 5V
0.30
0.7
INMOS
NMOS Current Limit
VIN = 2.5V
850
mA
IPS
Powersave Operation Current
Threshold
3
mA
%
Max Duty Cycle
fSW
Switching Frequency
VSHDNNH
SHDNN Input High
VSHDNNL
SHDNN Input Low
ISHDNN
SHDNN Input Current
AS1322A only
2
VFB = 1V, TAMB = TMIN to TMAX
80
87
TAMB = 25ºC
0.95
1.2
1.5
TAMB = TMIN to TMAX
0.85
1.2
1.5
1
VSHDNN = 5.0V
Ω
Ω
MHz
V
0.01
0.35
V
1
µA
1. Minimum VIN operation after start-up is only limited by the battery’s ability to provide the necessary power as it
enters a deeply discharged state.
2. Specification is guaranteed by design and not 100% production tested.
3. IQPWS is measured at VOUT. Multiply this value by VOUT/VIN to get the equivalent input (battery) current.
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Revision 1.07
4 - 17
AS1322
Data Sheet
- 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
Figure 3. Powersave mode threshold vs. VIN,
VOUT = 3.0V
Figure 4. Efficiency vs. Output Current,
VOUT = 3.3V
100
90
25
Efficiency (%) .
Output Current (mA)
.
30
20
15
10
5
VIN = 2.4V
80
VIN = 1.5V
70
VIN = 1.0V
60
50
40
30
0
0.5 0.75
1
1.25 1.5 1.75
2
1
2.25 2.5
10
3.36
3.5
3.34
3
3.32
3.3
3.28
3.26
2.5
2
1.5
1
0.5
0
-25
0
25
50
75
100
0
0.5
1
Temperature (°C)
1.5
900
1.4
.
1000
800
1.3
Output Current (mA)
Startup Voltage (V) .
2
2.5
3
3.5
Figure 8. Output Current vs. Battery Voltage;
VOUT = 3.3V, 3% Tolerance
1.6
700
1.2
1.1
1
5V
3.3V
0.8
1.5
Battery Voltage (V)
Figure 7. Startup Voltage vs. Output Current;
0.9
1000
Figure 6. Output Voltage vs. Battery Voltage;
VOUT = 3.3V, IOUT = 10mA
Output Voltage (V) .
Output Voltage (V) .
Figure 5. Output Voltage vs. Temperature;
VOUT = 3.3V, IOUT = 10mA
3.24
-50
100
Output Current (mA)
Battery Voltage (V)
0.7
600
500
400
300
200
100
0.6
0
0.1
1
10
100
0.5
Output Current (mA)
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1
1.5
2
2.5
3
Battery Voltage (V)
Revision 1.07
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AS1322
Data Sheet
- 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 9. Output Current vs. Battery Voltage;
VOUT = 5.0V, 3% Tolerance
Figure 10. No Load Battery Current vs. VBATT
VOUT = 3.3V, TAMB = 25ºC
900
1000
Battery Current (µA) .
.
800
Output Current (mA)
700
600
500
400
300
200
100
100
0
10
0.5
1
1.5
2
2.5
3
3.5
4
1.2 1.4 1.6 1.8
Battery Voltage (V)
2
2.2 2.4 2.6 2.8
Figure 12. SW Pin Fixed Frequency Continuous Current
VIN = 1.3V, VOUT = 3.3V, L = 10µH, C = 10µF, IOUT = 100mA
1V/Div
100ns/Div
100ns/Div
1mA
VOUT(AC)
40mA
IOUT
100mA
60mA 100mV/Div
Figure 14. Fixed Frequency vs. Powersave Operation
VIN = 1.3V, VOUT = 3.3V, L = 10µH, C = 10µF
100mV/Div
Figure 13. VOUT Transient Response.
VIN = 1.3V, VOUT = 3.3V, L = 10µH, C = 10µF
VOUT(AC)
0V
VSW
0V
VSW
1V/Div
Figure 11. SW Pin Antiringing Operation
VIN = 1.3V, VOUT = 3.3V, L = 10µH, C = 10µF, IOUT = 5mA
IOUT
3
Battery Voltage (V)
100µs/Div
10ms/Div
Parts used for measurments: 10µH (MOS6020-103ML) Inductor, 10µF (GRM31CR70J106KA01L) CIN and COUT
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Revision 1.07
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AS1322
Data Sheet
- Detailed Description
8 Detailed Description
The AS1322/AS1322B can operate from a single-cell input voltage (VIN) below 1V, and feature fixed frequency
(1.2MHz) and current mode PWM control for exceptional line- and load-regulation. With low RDS(ON) and gate charge
internal NMOS and PMOS switches, the devices maintain high-efficiency from light to heavy loads.
Modern portable devices frequently spend extended time in low-power or standby modes, switching to high powerdrain only when certain functions are enabled. The AS1322A and the AS1322B are ideal for portable devices since
they maintain high-power conversion efficiency over a wide output power range, thus increasing battery life in these
types of devices.
In addition to high-efficiency at moderate and heavy loads, the AS1322A includes an automatic powersave mode that
improves efficiency of the power converter at light loads. The powersave mode is initiated if the output load current
falls below a factory programmed threshold (see Figure 3 on page 5).
Note: The AS1322B does not support powersave mode and provides continuous operation at light loads, eliminating
low-frequency VOUT ripple at the expense of light load efficiency.
Figure 15. Block Diagram
L1
4.7µH
1.5V
Single
Cell
6
VIN
CIN
1µF
Start Up
OSC
A
B
1
SW
PWM
Control
Slope
Compensator
VOUT
CFF*
Current
Sense
Σ
3.3V
Output
5
0.45Ω
0.35Ω
Sync Drive
Control
1.2MHz
Ramp
Generator
2.3V
–
VOUT
Good
+
A/B
MUX
AS1322
+
PWM –
Comp
–
4
SHDNN
Shutdown
Control
Powersave
Shutdown
Powersave
Operation
Control
RC
80kΩ
CC
150pF
3
–
gm Error
Amp
+
COUT
4.7µF
FB
CP2
2.5pF
1.23V
Ref
2
R1
1.02MΩ
1%
R2
640kΩ
1%
GND
* Optional
Low-Voltage Start-Up
The AS1322 requires VIN of only 0.85V (typ) or higher to start up. The low-voltage start-up circuitry controls the internal
NMOS switch up to a maximum peak inductor current of 850mA (typ), with 1.5ms (approx.) off-time during start-up,
allowing the devices to start up into an output load.
With a VOUT > 2.3V, the start-up circuitry is disabled and normal fixed-frequency PWM operation is initiated. In this
mode, the AS1322 operates independent of VIN, allowing extended operating time as the battery can drop to several
tenths of a volt without affecting output regulation. The limiting factor for the application is the ability of the battery to
supply sufficient energy to the output.
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AS1322
Data Sheet
- Detailed Description
Low-Noise Fixed-Frequency Operation
Oscillator
The AS1322 switching frequency is internally fixed at 1.2MHz allowing the use of very small external components.
Error Amplifier
The integrated error amplifier is an internally compensated trans-conductance (gm) type (current output). The internal
1.23V reference voltage is compared to the voltage at pin FB to generate an error signal at the output of the error
amplifier. A voltage divider from VOUT to GND programs the output voltage from 2.5 to 5V via pin FB as:
VOUT = 1.23V(1 + (R1/R2))
(EQ 1)
Current Sensing
A signal representing the internal NMOS-switch current is summed with the slope compensator. The summed signal is
compared to the error amplifier output to provide a peak current control command for the PWM. Peak switch current is
limited to approximately 850mA independent of VIN or VOUT.
Zero Current Comparator
The zero current comparator monitors the inductor current to the output and shuts off the PMOS synchronous rectifier
once this current drops to 20mA (approx.). This prevents the inductor current from reversing polarity and results in
improved converter efficiency at light loads.
Anti-Ringing Control
Anti-ringing control circuitry prevents high-frequency ringing on pin SW as the inductor current approaches zero. This
is accomplished by damping the resonant circuit formed by the inductor and the capacitance on pin SW (CSW).
Powersave Operation (AS1322A)
In light load conditions, the integrated powersave feature removes power from all circuitry not required to monitor
VOUT. When VOUT has dropped approximately 1% from nominal, the AS1322A powers up and begins normal PWM
operation.
COUT (see Figure 15 on page 7) recharges, causing the AS1322A to re-enter powersave mode as long as the output
load remains below the powersave threshold. The frequency of this intermittent PWM is proportional to load current;
i.e., as the load current drops further below the powersave threshold, the AS1322A turns on less frequently. When the
load current increases above the powersave threshold, the AS1322A will resume continuous, seamless PWM operation.
Notes:
1. An optional capacitor (CFF) between pins VOUT and FB in some applications can reduce VOUTp-p ripple and input
quiescent current during powersave mode. Typical values for CFF range from 15 to 220pF.
2. In powersave mode the AS1322A draws only 30µA from the output capacitor(s), greatly improving converter efficiency.
Shutdown
When pin SHDNN is low the AS1322 is switched off and <1µA current is drawn from battery; when pin SHDNN is high
the device is switched on. If SHDNN is driven from a logic-level output, the logic high-level (on) should be referenced
to VOUT to avoid intermittently switching the device on.
Note: If pin SHDNN is not used, it should be connected directly to pin OUT. VOUT is held at approximately VIN - 0.6V
during shutdown.
In shutdown the battery input is connected to the output through the inductor and the internal synchronous rectifier PFET. Due to the body diode of the internal synchronous rectifier PFET, VOUT is held at approximately VIN - 0.6V during
shutdown. This allows the input battery to provide backup power for devices such as an idle microcontroller, memory,
or real-time-clock, without the usual diode forward drop. In this way a separate backup battery is not needed.
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8 - 17
AS1322
Data Sheet
- Application Information
9 Application Information
The AS1322 is perfectly suited for LED matrix displays, bar-graph displays, instrument-panel meters, dot matrix displays, set-top boxes, white goods, professional audio equipment, medical equipment, industrial controllers to name a
few applications.
Along with Figure 1 on page 1, Figures 16-19 depict a few of the many applications for which the AS1322 converters
are perfectly suited.
Figure 16. Single AA Cell to 3.3V Synchronous Boost Converter with Load Disconnect in Shutdown
L1
4.7µH
D1
1 SW
AA
Battery
C1
4.7µF
On
Off
VOUT
3.3V, 160mA
5
6
VOUT
VIN
AS1322
4
C2
4.7µF
R3
510kΩ
R1
1.02MΩ
1%
3
SHDNN
FB
R2
604kΩ
1%
2 GND
Q1
R3
510kΩ
Figure 17. Single Lithium Cell to 5V, 250mA
2Ω
100nF
L1
4.7µH
Optional
Snubber
D1
1 SW
5
6
Lithium
Battery
VOUT
VIN
C1
4.7µF
On
Off
AS1322
4
C2
4.7µF
C3
100pF
3
SHDNN
FB
2 GND
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R1
1.02MΩ 1%
Revision 1.07
R2
332kΩ 1%
9 - 17
AS1322
Data Sheet
- Application Information
Figure 18. Single AA Cell to ±3V Synchronous Boost Converter
L1
4.7µH
C3
1µF
1 SW
AA
Battery
C1
4.7µF
On
Off
VOUT1
3V, 90mA
5
6
VOUT
VIN
C2
4.7µF
R1
1.02MΩ
1%
AS1322
3
4
D1
FB
SHDNN
D2
C4
10µF
R2
750kΩ
1%
2 GND
VOUT2
-3V, 10mA
Figure 19. Single AA Cell to 2.5V Synchronous Boost Converter
L1
4.7µH
D1
1
SW
5
6
AA
Battery
C1
10µF
On
Off
R1
1.02MΩ
1%
AS1322
C2
10µF
3
4
FB
SHDNN
2
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VOUT
2.5V, 230mA
VOUT
VIN
GND
R2
1.02MΩ
1%
Revision 1.07
10 - 17
AS1322
Data Sheet
- Application Information
External Component Selection
Inductor Selection
The fast switching frequency (1.2MHz) of the AS1322 allows for the use of small surface mount or chip inductor for the
external inductor (see Figure 15 on page 7).
The required minimum values for the external inductor are:
!
3.3µH for applications ≤ 3.6V
!
4.7µH for applications > 3.6V
Larger inductor values allow greater output current capability by reducing the inductor ripple current. Increasing the
inductance above 10µH will increase size while providing negligible improvement in output current capability.
The approximate output current capability of the AS1322 versus inductor value is given in:
V IN ⋅ D
I OUT ( MAX ) = η ⋅ ⎛ I P – ------------------⎞ ⋅ ( 1 – D )
⎝
f ⋅ L ⋅ 2⎠
(EQ 2)
Where:
η is the estimated efficiency;
IP is the peak current limit value (0.6A);
VIN is the input voltage;
D is the steady-state duty ratio = (VOUT - VIN)/VOUT;
f is the switching frequency (1.2MHz typ);
L is the inductor value.
The inductor current ripple is typically set for 20 to 40% of the maximum inductor current (IP). High-frequency ferrite
core inductor materials reduce frequency dependent power losses compared to less expensive powdered iron types,
which result in improved converter efficiency.
2
The inductor should have low ESR to reduce the I R power losses, and must be able to handle the peak inductor current without saturating. Molded chokes and some chip inductors normally do not have enough core to support the peak
inductor currents of the AS1322 (850mA typ). To minimize radiated noise, use a toroid, pot core, or shielded bobbin
inductor.
Table 5. Recommended Inductors
Part Number
L
DCR
MOS6020-103ML
10µH
93mΩ
1A
6.8x6.0x2.4mm
MOS6020-472ML
4.7µH
50mΩ
1.5A
6.8x6.0x2.4mm
MOS6020-332ML
3.3µH
46mΩ
1.8A
6.8x6.0x2.4mm
CDRH4D18-100
10µH
200mΩ
0.61A
6.9x5.0x2.0mm
CDRH4D18-6R8
6.8µH
200mΩ
0.76A
6.9x5.0x2.0mm
CR43-6R8
6.8µH
131.2mΩ
0.95A
4.8x4.3x3.5mm
CDRH4D18-4R7
4.7µH
162mΩ
0.84A
6.9x5.0x2.0mm
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Current Rating Dimensions (L/W/T)
Revision 1.07
Manufacturer
Coilcraft
www.coilcraft.com
Sumida
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11 - 17
AS1322
Data Sheet
- Application Information
Figure 20. Efficiency Comparison of Different Inductors, VIN = 1.5V, VOUT = 3.3V
90
92
85
90
80
88
Efficiency (%)
Efficiency (%)
75
70
65
60
10uH - Coi l cr af t (M OS6020-103M L)
55
10uH - Sumi da(CDRH4D18-100)
84
82
10uH - Coi l cr af t (M OS6020-103M L)
80
6. 8uH - Sumi da(CDRH4D18-6R8)
50
86
10uH - Sumi da(CDRH4D18-100)
6. 8uH - Sumi da(CDRH4D18-6R8)
6. 8uH - Sumi da(CR43-6R8)
6. 8uH - Sumi da(CR43-6R8)
4. 7uH - Coi l cr af t (M OS6020-472M L)
45
78
4. 7 uH - Sumi da(CDRH4D18-4R7)
4. 7uH - Coi l c r af t (M OS6020-472M L)
4. 7 uH - Sumi da(CDRH4D18-4R7)
3. 3 uH - Coi l cr af t (M OS6020-332M L)
3. 3 uH - Coi l c r af t (M OS6020-332M L)
40
S
76
0.1
1
10
10
Output Current (mA)
i
8
Output Current (mA)
100
Output Capacitor Selection
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 2.2 to 10µF output capacitor is sufficient for most
applications. Larger values up to 22µF may be used to obtain extremely low output voltage ripple and improve transient response.
An additional phase lead capacitor may be required with output capacitors larger than 10µF to maintain acceptable
phase margin. X5R and X7R dielectric materials are recommended due to their ability to maintain capacitance over
wide voltage and temperature ranges.
Table 6. Recommended Output Capacitor
Part Number
C
JMK212BJ226MG-T
22µF ±20%
TC Code Rated Voltage
X5R
6.3V
Dimensions (L/W/T)
2x1.3x1.3mm
Manufacturer
Taiyo Yuden
www.t-yuden.com
Input Capacitor Selection
Low ESR input capacitors reduce input switching noise and reduce the peak current drawn from the battery. Ceramic
capacitors are recommended for input decoupling and should be located as close to the device as is practical. A 4.7µF
input capacitor is sufficient for most applications. Larger values may be used without limitations.
Table 7. Recommended Input Capacitor
Part Number
C
GRM31CR70J106KA01L 10µF ±10%
TC Code Rated Voltage Dimensions (L/W/T)
X7R
6.3V
3.2x1.6x1.6mm
Manufacturer
Murata
www.murata.com
Diode Selection
A Schottky diode should be used to carry the output current for the time it takes the PMOS synchronous rectifier to
switch on. For VOUT < 4.5V a Schottky diode is optional, although using one will increase device efficiency by 2 to 3%.
Note: Do not use ordinary rectifier diodes, since the slow recovery times will compromise efficiency.
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Revision 1.07
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AS1322
Data Sheet
- Application Information
PCB Layout Guidelines
The high-speed operation of the AS1322 requires proper layout for optimum performance. Figure 21 shows the recommended component layout.
!
A large ground pin copper area will help to lower the device temperature.
!
A multi-layer board with a separate ground plane is recommended.
!
Traces carrying large currents should be direct.
!
Trace area at pin FB should be as small as is practical.
!
The lead-length to the battery should be as short as is practical.
Figure 21. Recommended Single-Layer Component Placement
Optional
1 SW
VIN 6
AS1322
VIN
CIN
R2
2 GND
VOUT 5
SHDNN
3
FB SHDNN
R1
4
COUT
VOUT
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Revision 1.07
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AS1322
Data Sheet
- Package Drawings and Markings
10 Package Drawings and Markings
The device is available in a 6-pin TSOT-23 package.
Figure 22. 6-pin TSOT-23 Package
3
A
4
A
3
4
6
7
Notes:
1. Dimensioning and tolerancing conform to ASME Y14.5M - 1994.
2. Dimensions are in millimeters.
3. Dimension D does not include mold flash, protrusions, or gate burrs. Mold flash, protrusions, and gate burrs shall
not exceed 0.15mm per end. Dimension E1 does not include interlead flash or protrusion. Interlead flash or protrusion shall not exceed 0.15mm per side. Dimensions D and E1 are determined at datum H.
4. The package top can be smaller than the package bottom. Dimensions D and E1 are determined at the outermost
extremes of the plastic body exclusive of mold flash, tie bar burrs, gate burrs, and interlead flash, but include any
mistmatches between the top of the package body and the bottom. D and E1 are determined at datum H.
5. Datums A and B are to be determined at datum H.
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Revision 1.07
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AS1322
Data Sheet
- Package Drawings and Markings
6. These dimensions apply to the flat section of the lead between 0.08 and 0.15mm from the lead tip.
7. Dimension b does not include dambar protrusion. Allowable dambar protrusion shall be 0.08mm total in excess of
the b dimension at the maximum material condition. The dambar cannot be located on the lower radius of the foot.
Minimum space between the protrusion and an adjacent lead shall not be less than 0.77mm.
Symbol
A
A1
A2
b
b1
c
c1
D
E
E1
e
e1
L
L1
L2
N
R
R1
θ
θ1
aaa
bbb
ccc
ddd
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Min
Typ
0.01
0.84
0.30
0.31
0.12
0.08
0.05
0.87
0.30
0.35
0.15
0.13
2.90BSC
2.80BSC
1.60BSC
0.95BSC
1.90BSC
0.40
0.60REF
0.25BSC
6
0.10
0.10
0º
Max
1.00
0.10
0.90
0.45
0.39
0.20
0.16
Notes
6,7
6,7
6
6
3,4
3,4
3,4
0.50
0.25
4º
8º
4º
10º
12º
Tolerances of Form and Position
0.15
0.25
0.10
0.20
Revision 1.07
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AS1322
Data Sheet
- Ordering Information
11 Ordering Information
The device is available as the standard products listed in Table 8.
Table 8. Ordering Information
Model
Marking
Descriptiom
Delivery Form
Package
AS1322A-BTTT
ASKQ
Low Voltage, Micropower, DC-DC Step-Up
Converter with Automatic Powersave Operation
Tape and Reel
6-pin TSOT-23
AS1322B-BTTT
ASKZ
Low Voltage, Micropower, DC-DC Step-Up
Converter with Continuous Switching
Tape and Reel
6-pin TSOT-23
All devices are RoHS compliant and free of halogene substances.
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Revision 1.07
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AS1322
Data Sheet
Copyrights
Copyright © 1997-2007, austriamicrosystems AG, Schloss Premstaetten, 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.
Disclaimer
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 lifesustaining 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.
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
Headquarters
austriamicrosystems AG
A-8141 Schloss Premstaetten, Austria
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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