A7220M8VR [AITSEMI]
DC-DC CONVERTER BUCK (STEP-DOWN);型号: | A7220M8VR |
厂家: | AiT Semiconductor |
描述: | DC-DC CONVERTER BUCK (STEP-DOWN) DC-DC转换器 |
文件: | 总12页 (文件大小:479K) |
中文: | 中文翻译 | 下载: | 下载PDF数据表文档文件 |
A7220
AiT Semiconductor Inc.
www.ait-ic.com
DC-DC CONVERTER BUCK (STEP-DOWN)
4.3V TO 18V INPUT, 2A SYNCHRONOUS STEP-DOWN
CONVERTER WITH FAST TRANSIENT RESPONSE
DESCRIPTION
FEATURES
The A7220 is a current mode synchronous
buck converter, and has proprietary
2A Output Current
High Efficient Integrated FETs Optimized for portable
application:
95mΩ (High side) and 90mΩ (Low side)
High Efficiency
Up to 95% Efficiency @ 5V Input, 3.3V Output
Up to 93% Efficiency @ 12V Input, 3.3V Output
Wide Input Voltage Range: 4.3V to 18V @ 2A loading
Wide Output Voltage Range: 0.918V to 14V @2A
loading ( 32W output @max)
Low Output Ripple and Allows Ceramic Output Capacitor
Thermal Shutdown Protection
340KHz Switching Frequency(fsw)
Cycle By Cycle Over Current Limit
+/-1.5% High Accuracy Feedback Voltage
Available in SOP8 and package
a
W-mode™® Gm curvature circuit that enables
fast transient response, enables the device to
adopt to both low ESR output capacitors, such
as POSCAP or SP-CAP, and ultra-low ESR
ceramic capacitors.
The A7220 operates from 4.3V to 18V VIN
input, and the output voltage can be
programmed between 0.918V to 14V with 2A
output current, and +/-1.5% high accuracy
output voltage.
Due to 95mΩ (High side) and 90mΩ (Low
side) integrated FETs, the A7220 works in high
efficiency (up to 94% @12V Input, 3.3V output)
The A7220 is available in SOP8 Package.
APPLICATION
Wide Range of Applications for Low Voltage System
ORDERING INFORMATION
Digital TV Power Supply
High Definition Blu-ray Disc Players
Networking Home Terminal
Digital STB
Package Type
SOP8
Part Number
A7220M8R
A7220M8VR
Ideal for Portable Applications
M
R: Tape & Reel
Note
TYPICAL APPLICATION
V: Halogen free Package
AiT provides all RoHS products
Suffix “ V “ means Halogen free Package
REV3.0
- JUL 2010 RELEASED, FEB 2012 UPDATED -
- 1 -
A7220
AiT Semiconductor Inc.
www.ait-ic.com
DC-DC CONVERTER BUCK (STEP-DOWN)
4.3V TO 18V INPUT, 2A SYNCHRONOUS STEP-DOWN
CONVERTER WITH FAST TRANSIENT RESPONSE
PIN DESCRIPTION
Top View
Pin #
1
Symbol
BS
Function
Supply input for high-side NFET gate driver (boost terminal). Connect
capacitor from this pin to SW pin. An internal PN diode is connected
between VREG to BS pin.
2
3
IN
Power input and connected to high side NFET drain
Switch node connection between high-side NFET and low-side NFET.
Also serve as inputs to current comparators.
SW
4
5
GND
FB
Signal ground pin, also serve as ground returns for low-side NFET.
Converter feedback input. Connect with feedback resistor divider.
Compensation Node. Used to compensate control loop. Connect a
series RC network from COMP to G. In some cases, an additional
capacitor is required
6
COMP
7
8
EN
SS
Enable control input
Soft-start control. A external capacitor should be connected to GND.
REV3.0
- JUL 2010 RELEASED, FEB 2012 UPDATED -
- 2 -
A7220
AiT Semiconductor Inc.
www.ait-ic.com
DC-DC CONVERTER BUCK (STEP-DOWN)
4.3V TO 18V INPUT, 2A SYNCHRONOUS STEP-DOWN
CONVERTER WITH FAST TRANSIENT RESPONSE
ABSOLUTE MAXIMUM RATINGS
IN
-0.3V to 20V
-0.3V to 25V
-2V to 20V
BS
SW
Voltage Range
SW (10 ns transient)
-2.5V to 21V
-0.3V to 5.5V
-0.3V to 8V
FB,SS,COMP
EN
TJ, Operation Junction
TSTG, Storage temperature
-40℃ to +150℃
-55℃ to +150℃
Stresses above 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 the Electrical Characteristics are not implied. Exposure to absolute maximum
rating conditions for extended periods may affect device reliability.
REV3.0
- JUL 2010 RELEASED, FEB 2012 UPDATED -
- 3 -
A7220
AiT Semiconductor Inc.
www.ait-ic.com
DC-DC CONVERTER BUCK (STEP-DOWN)
4.3V TO 18V INPUT, 2A SYNCHRONOUS STEP-DOWN
CONVERTER WITH FAST TRANSIENT RESPONSE
ELECTRICAL CHARACTERISTICS
Over operating free-air temperature range(unless otherwise noted) VIN=12V, TA=25℃
Parameter
Operating-non-switching supply
current
Symbol
Conditions
VIN current, TA=25℃,
EN=1.8V,VFB=1.0V
VEN=0V
Min
Typ.
Max
2.0
Unit
mA
IIN
-
1.3
Shut Down Supply Current
Feedback Voltage
Feedback Overvoltage
Threshold
ISDN
VFB
-
2
4
μA
V
4.3V ≤VIN≤18V
0.900
0.913
0.926
OVP
Aea
Gea
-
-
-
1.1
1000
900
-
-
-
V
Error Amplifier Voltage Gain
Error Amplifier
V/V
μA/V
ΔIC=+/-10μA
Transconductance
High Side Switch ON Resistance RDS(on)_1
Low Side Switch ON Resistance RDS(on)_2
High Side Switch Leakage
-
-
95
90
-
-
mΩ
mΩ
ILEAKGAE VEN=0V, VSW=0V
-
-
10
μA
Current
High Side Switch Current Limit
Low Side Switch Current Limit
COMP Voltage to Current Sense
Transconductance
ILM_H
ILM_L
Minimum Duty Cycle
From Drain to Source
2.8
-
3.5
1.0
-
-
A
A
Gcs
-
-
-
-
3.5
340
100
-
-
-
A/V
KHz
KHz
Switching Frequency
Short Circuit Switching
Frequency
Fsw_1
Fsw_2
VFB=0V
Maximum Duty Cycle
Minimum ON Time
Dmax
TON_min
VEN_1
VFB=1.0V
90
220
1.5
-
-
%
ns
V
EN Threshold Voltage
EN Threshold voltage’s
Hysteresis
VEN Rising
1.1
-
2.0
VHys_1
100
-
mV
EN Lockout Threshold Voltage
EN Lockout Hysteresis
Input Under Voltage Lockout
Threshold
VEN_2
VHys_2
1.8
-
2.0
2.2
-
V
210
mV
VUVLO
VIN Rising
3.0
3.6
4.2
V
REV3.0
- JUL 2010 RELEASED, FEB 2012 UPDATED -
- 4 -
A7220
AiT Semiconductor Inc.
www.ait-ic.com
DC-DC CONVERTER BUCK (STEP-DOWN)
4.3V TO 18V INPUT, 2A SYNCHRONOUS STEP-DOWN
CONVERTER WITH FAST TRANSIENT RESPONSE
Parameter
Conditions
Symbol
VHys_3
ISS
Min
Typ.
600
Max
4.55
Unit
mV
μA
Input Under Voltage Lockout
Threshold Hysteresis
Soft-Start Current
VSS=0V
4.25
4.40
Setting Feedback Voltage by
Using Soft-Start Voltage
Only when VSS <
0.85V by adding
resistor on SS pin
VSS=
VSS+30
mV
VFB-SS
mV
Iss*RSS=4.4μA*RSS
CSS=0.1μF
Soft-Start Period
TSS
15
ms
℃
Thermal Shutdown
TSD
160
REV3.0
- JUL 2010 RELEASED, FEB 2012 UPDATED -
- 5 -
A7220
AiT Semiconductor Inc.
www.ait-ic.com
DC-DC CONVERTER BUCK (STEP-DOWN)
4.3V TO 18V INPUT, 2A SYNCHRONOUS STEP-DOWN
CONVERTER WITH FAST TRANSIENT RESPONSE
TEST CIRCUIT
VIN=12V,VOUT=3.3V, L=10μH, CIN=10μF, COUT=22μF, TA=+25℃
1. Fast Transient Response (20A/μs) 2. Startup through Enable
3. 1A Load Operation
4. 2A Load Operation
5. Shutdown through Enable
6. Short Circuit Recovery
REV3.0
- JUL 2010 RELEASED, FEB 2012 UPDATED -
- 6 -
A7220
AiT Semiconductor Inc.
www.ait-ic.com
DC-DC CONVERTER BUCK (STEP-DOWN)
4.3V TO 18V INPUT, 2A SYNCHRONOUS STEP-DOWN
CONVERTER WITH FAST TRANSIENT RESPONSE
APPLICATION INFORMATION
APPLICATION SCHEMATIC (1)
With Electrolytic Capacitor
Figure 1
Compatible with main competitors without any external component change
RECOMMENDED COMPONENT SELECTION
VOUT
1.0V
1.2V
1.8V
2.5V
3.3V
5.0V
1.0V
1.2V
1.8V
2.5V
3.3V
5.0V
COUT
22Μf Ceramic X2
22μF Ceramic X2
22μF Ceramic X2
22μF Ceramic X2
22μF Ceramic X2
22μF Ceramic X2
47μF SP Cap
R1
R2
R3(comp)
50Ω
C4(comp)
10nF
C5(optional) L(inductor)
1.0K
10K
15K
10K
6.8K
10K
6.8K
10K
15K
10K
6.8K
10K
6.8K
OPEN
OPEN
OPEN
OPEN
OPEN
OPEN
OPEN
OPEN
OPEN
OPEN
OPEN
OPEN
3.3μH
3.3μH
4.7μH
6.8μH
10μH
22μH
3.3μH
3.3μH
4.7μH
6.8μH
10μH
22μH
4.7K
100Ω
300Ω
1.5KΩ
2.2KΩ
2.7KΩ
50Ω
10nF
9.7K
3.3nF
3.3nF
3.3nF
3.3nF
10nF
12.0K
26.1K
30.0K
1.0K
47μF SP Cap
4.7K
100Ω
300Ω
1.5KΩ
2.2KΩ
2.7KΩ
10nF
47μF SP Cap
9.7K
3.3nF
3.3nF
3.3nF
3.3nF
47μF SP Cap
12.0K
26.1K
30.0K
47μF SP Cap
47μF SP Cap
REV3.0
- JUL 2010 RELEASED, FEB 2012 UPDATED -
- 7 -
A7220
AiT Semiconductor Inc.
www.ait-ic.com
DC-DC CONVERTER BUCK (STEP-DOWN)
4.3V TO 18V INPUT, 2A SYNCHRONOUS STEP-DOWN
CONVERTER WITH FAST TRANSIENT RESPONSE
VOUT
1.0V
1.2V
1.8V
2.5V
3.3V
5.0V
12V
COUT
R1
R2
R3(comp)
50Ω
C4(comp)
10nF
C5(optional)
150pF
150pF
150pF
150pF
150pF
150pF
150pF
L(inductor)
3.3μH
3.3μH
4.7μH
6.8μH
10μH
470μF/6.3V/Electrolytic
470μF/6.3V/Electrolytic
470μF/6.3V/Electrolytic
1.0K
4.7K
9.7K
10K
15K
10K
6.8K
10K
6.8K
5.1K
100Ω
10nF
300Ω
3.3nF
3.3nF
3.3nF
3.3nF
3.3nF
470μF/6.3V/Electrolytic 12.0K
470μF/6.3V/Electrolytic 26.1K
1.5KΩ
2.2KΩ
2.7KΩ
3.3KΩ
470μF/10V/Electrolytic
470μF/25V/Electrolytic
30.0K
62.0K
22μH
47μH
REV3.0
- JUL 2010 RELEASED, FEB 2012 UPDATED -
- 8 -
A7220
AiT Semiconductor Inc.
www.ait-ic.com
DC-DC CONVERTER BUCK (STEP-DOWN)
4.3V TO 18V INPUT, 2A SYNCHRONOUS STEP-DOWN
CONVERTER WITH FAST TRANSIENT RESPONSE
APPLICATION SCHEMATIC (2)
Fast Transient Response Without Electrolytic Capacitor
Figure 2
RECOMMENDED COMPONENT SELECTION
VOUT
1.0V
1.2V
1.8V
2.5V
3.3V
5.0V
1.0V
1.2V
1.8V
2.5V
3.3V
5.0V
COUT
R1
R2
R3(comp)
3.0KΩ
3.0KΩ
3.0KΩ
3.0KΩ
3.0KΩ
3.0KΩ
3.0KΩ
3.0KΩ
3.0KΩ
3.0KΩ
3.0KΩ
3.0KΩ
C4(comp)
1.0nF
1.0nF
1.0nF
1.0nF
1.0nF
1.0nF
1.0nF
1.0nF
1.0nF
1.0nF
1.0nF
1.0nF
Cff
L(inductor)
2.2μH
2.2μH
3.3μH
4.7μH
6.8μH
22μH
22μF Ceramic X2
22μF Ceramic X2
22μF Ceramic X2
22μF Ceramic X2
22μF Ceramic X2
22μF Ceramic X2
47μF SP Cap
2.0K
20K
20K
20K
20K
20K
20K
20K
20K
20K
20K
20K
20K
2.2nF
1.0nF
680pF
680pF
680pF
390pF
2.2nF
1.0nF
680pF
680pF
680pF
390pF
6.3K
19.4K
34.5K
52.2K
89.5K
2.0K
2.2μH
2.2μH
3.3μH
4.7μH
6.8μH
22μH
47μF SP Cap
6.3K
47μF SP Cap
19.4K
34.5K
52.2K
89.5K
47μF SP Cap
47μF SP Cap
47μF SP Cap
REV3.0
- JUL 2010 RELEASED, FEB 2012 UPDATED -
- 9 -
A7220
AiT Semiconductor Inc.
www.ait-ic.com
DC-DC CONVERTER BUCK (STEP-DOWN)
4.3V TO 18V INPUT, 2A SYNCHRONOUS STEP-DOWN
CONVERTER WITH FAST TRANSIENT RESPONSE
APPLICATION NOTES
a) C2 ceramic capacitor as close as possible to the chip PIN2 and PIN4 placed;
b) When using 47μH inductors, each switching and transmission of energy, the output of the
need for greater capacitance, so that the large-signal. The feedback loop is stable. 47μH
inductor, the output is required with greater than or equal to 330μF electrolytic capacitor
for energy Bulk.
c) The current path is as short as possible and as far as possible with the chip in the same
PCB level. Played the hole cross-layer connections to avoid the high current path.
d) If feasible, cost and high efficiency design, should make full use of ceramic capacitors or
smaller ESR (such as: 30mohm) electrolytic Capacity, efficiency can be effectively
increased by 1%.
e) EN pin (pin 7) on the pull-up resistor is not less than 100KΩ.
f) If more than one chip share the same input capacitance of the need to adjust of 8
Jiaoruan starting capacitor capacitance value of time-delayed start of each chip to
regulate avoid multiple chip start to impact on the power input capacitance. Delay Time:
delay 15ms per 100nF capacitor.
REV3.0
- JUL 2010 RELEASED, FEB 2012 UPDATED -
- 10 -
A7220
AiT Semiconductor Inc.
www.ait-ic.com
DC-DC CONVERTER BUCK (STEP-DOWN)
4.3V TO 18V INPUT, 2A SYNCHRONOUS STEP-DOWN
CONVERTER WITH FAST TRANSIENT RESPONSE
PACKAGE INFORMATION
Dimension in SOP8 (Unit: mm)
Symbol
Min
Max
A
A1
A2
b
1.350
0.100
1.350
0.330
0.170
4.700
3.800
5.800
1.750
0.250
1.550
0.510
0.250
5.100
4.000
6.200
c
D
E
E1
e
1.270(BSC)
0.400
0°
L
1.270
8°
θ
REV3.0
- JUL 2010 RELEASED, FEB 2012 UPDATED -
- 11 -
A7220
AiT Semiconductor Inc.
www.ait-ic.com
DC-DC CONVERTER BUCK (STEP-DOWN)
4.3V TO 18V INPUT, 2A SYNCHRONOUS STEP-DOWN
CONVERTER WITH FAST TRANSIENT RESPONSE
IMPORTANT NOTICE
AiT Semiconductor Inc. (AiT) reserves the right to make changes to any its product, specifications, to
discontinue any integrated circuit product or service without notice, and advises its customers to obtain the
latest version of relevant information to verify, before placing orders, that the information being relied on is
current.
AiT Semiconductor Inc.'s integrated circuit products are not designed, intended, authorized, or warranted to
be suitable for use in life support applications, devices or systems or other critical applications. Use of AiT
products in such applications is understood to be fully at the risk of the customer. As used herein may
involve potential risks of death, personal injury, or servere property, or environmental damage. In order to
minimize risks associated with the customer's applications, the customer should provide adequate design and
operating safeguards.
AiT Semiconductor Inc. assumes to no liability to customer product design or application support. AiT
warrants the performance of its products of the specifications applicable at the time of sale.
REV3.0
- JUL 2010 RELEASED, FEB 2012 UPDATED -
- 12 -
相关型号:
©2020 ICPDF网 联系我们和版权申明