AMS4122 [ADMOS]
SINGLE 4A/DUAL 2A BUCK CONVERTER IN SO8; 4A单/双2A降压转换器采用SO8
| 型号： | AMS4122 |
| 厂家： | 
ADVANCED MONOLITHIC SYSTEMS |
| 描述： | SINGLE 4A/DUAL 2A BUCK CONVERTER IN SO8 |
| 文件： | 总6页 (文件大小：534K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
Advanced
Monolithic
Systems
AMS4122
SINGLE 4A/DUAL 2A BUCK CONVERTER IN SO8
RoHS compliant
FEATURES
APPLICATIONS
• 2 Independent Asynchronous Buck Converters in SO-8
• Internally compensated
• Built in soft start
• Enable with Zero current shut down
• 400KHz switching per output
• Audio Power Amplifiers
• Portable (Notebook) Computers
• Point of regulation for high performance electronics
• Consumer Electronics
• Desktop Computers
• Interleaved oscillator to reduced supply ripple
• Simply re-configures to 2 phase single output
• Up to 4A output in 2 phase mode
• Independent hiccup current limit
• LCD TVs and LCD monitors
• Distributed Power Systems
• Battery Chargers
• Pre-Regulator for Linear Regulators
GENERAL DESCRIPTION
AMS4122 is a dual switching regulator capable to deliver 2A for each channel. Internally Compensated internal Soft Start
makes AMS4122 one of the simplest and easiest switching regulators to use with the minimum external components. Each
regulator has independent hiccup current limit. The Enable pin turns both devices on when a voltage of 2.5V or higher it is
applied to EN pin. Since both devices share one single package the thermal protection turns off both devices when the die
temperature exceeds approximately 135°C. Both regulators are adjustable using a 0.600V reference for low output voltage
settings. The oscillators are 180° phase to each other to reduce the ripples on the input power supply and minimize the power
dissipation on the package. The device can be easily configured for Two Phase single output switching regulator capable of 5A
output load. By applying a 2.5V or greater on feedback pin of the second switching regulator the device enters in Two Phase
Mode. The first benefit of having a Two Phase device is reducing the output ripples by a factor of four as the single phase. The
second benefit is higher output current capability at overall low cost. AMS4122 combined with AMS4123 (2A Switching
Regulator + 1A LDO in SO-8) makes complete solution for LCD TV power requirements.
ORDERING INFORMATION
Package Type
SOIC EDP
TEMP. RANGE
PINCONNECTIONS
AMS4122S
-25°C to 125°C
8L SOIC
TYPICAL APPLICATION
SO Package (S)
1
2
8
7
6
5
SW1
SW2
PVIN
GND
F/B2
AVIN
3
4
EN
F/B1
Top View
Advanced Monolithic Systems, Inc. www.advanced-monolithic.com Phone (925) 443-0722 Fax (925) 443-0723
AMS4122
PIN DESCRIPTION
Pin Number
NAME
DESCRIPTION
1
2
3
SW2
This connects the inductor the Internal Switch2
Input Power Pin for SW2 from unregulated power supply
PVIN SW2
GND
Ground Pin connected to PCB ground plane. This pin is also the ground for internal
voltage reference.
4
F/B2
Feedback2. A resistor network of two resistors is used to set-up the output voltage
connected between Output2 to GND. The node between the two resistors is connected to
Feedback2 pin. In Two Phase Mode F/B2 should be connected to a voltage 2.5V or
higher
5
F/B1
Feedback1. A resistor network of two resistors is used to set-up the output voltage
connected between Output1 to GND. The node between the two resistors is connected to
Feedback1 pin.
6
7
8
EN
Enable. A voltage greater than 2.5V at this pin enables both devices operation.
Input Power Pin for SW1 and Analog Input Voltage that powers up the chip
This connects the inductor the Internal Switch1
PVIN SW1/AVIN
SW1
RECOMMANDED OPERATING CONDITIONS: The minimum input voltage should be 4.5V, however the device will
function as low as 4.0V. The maximum operating voltage should be 16V, the device will work at 17V but the switching loss is
higher. The best performance is at 1.5A output load per channel; however it works well with 2A load per channel. The minimum
supply voltage is Vout +1Vfor 1A load and Vout +1.1V for 2A load but higher than 4.0V. There is an internal UVLO that will
turn off the device if the input voltage is below 4.0V. When the input voltage exceeds 12V the output load current should be
maintain below 1.5A, due to switching loss the device will have lower performance.
Advanced Monolithic Systems, Inc. www.advanced-monolithic.com Phone (925) 443-0722 Fax (925) 443-0723
AMS4122
ABSOLUTE MAXIMUM RATINGS
VIN
F/B
EN
4.0V to 20V
-0.3 to +12.0V
-0.3V to +20V
Junction Temperature
Storage Temperature
Lead temperature
+150ºC
-65ºC to +150ºC
260ºC
ELECTRICAL CHARACTERISTICS
Electrical Characteristics at TA= 25 °C and VIN=12V (unless otherwise noted).
PARAMETER TEST CONDITIONS
Feedback voltage F/B-1 and F/B-2
AMS4122
Typ.
Units
Min.
Max.
0.590
0.6
2
0.610
2.5
V
A
V
<º
A
Full Load Output Current
Feedback2 (note 1)
Measured on each channel (note 4)
Two Phase Mode
1.3
180
4
2.5
Dual Output Mode
Phase Shift between Outputs
Current Limit
171
360
189
Per Output
Dual Phase Single Output Mode
Note(2)
Phase current match
Oscillator Frequency
Maximum Duty Cycle
Enable Threshold
10
%
KHz
%
400
440
100
2.5
120
0.7
V
Enable Hysteresis
mV
Enable Pull-up Current
µA
Under Voltage Lockout
Threshold Rising
3.5
V
Under Voltage Lockout
Threshold Hysteresis
150
100
1.5
mV
nA
Supply Current (Shutdown)
Supply Current (Quiescent)
Thermal Shutdown
VEN ≤ 0.4V
VEN ≥ 2.8V; VFB = 1.5V
1.9
mA
135
2.5
°C
W
Total Power dissipation
Note (3)
Notes: 1) When a 1.3V or greater is applied to F/B2, the device enters in Two Phase Mode of operation.
2) The oscillators for each switching regulator are shifted by 180º of each-other to accommodate dual phase operation and reduce the ripples in the input
power supply.
3) The power dissipation for SO-8 EDP package is limited to 2.5W rated at 25°C ambient temperatures. The thermal resistance Junction to Case is
45°C/W. Total power dissipation for both switching regulators should be taken in consideration when calculating the output current for each regulator.
4) The load current is specified for two output configuration. In two phase single output the maximum load current is double.
Advanced Monolithic Systems, Inc. www.advanced-monolithic.com Phone (925) 443-0722 Fax (925) 443-0723
AMS4122
TYPICAL PERFORMANCE WAVEFORM
AMS4122 DUAL OUTPUT Vin=12V
Low Output Current
AMS4122 DUAL OUTPUT Vin=12V
Full Load Output Current
DUAL OUTPUT Vin=7V
Full Load Output Current
DUAL PHASE
Full Load Output Current
Advanced Monolithic Systems, Inc. www.advanced-monolithic.com Phone (925) 443-0722 Fax (925) 443-0723
AMS4122
TYPICAL APPLICATION
2 Phase Single Output Application
VOUT = VREF (1+ R1/R2)
Dual Output Application
VOUT1 = VREF (1+ R1/R2)
VOUT2 = VREF (1+ R3/R4)
Advanced Monolithic Systems, Inc. www.advanced-monolithic.com Phone (925) 443-0722 Fax (925) 443-0723
AMS4122
PACKAGE DIMENSIONS inches (millimeters) unless otherwise noted.
8 LEAD SOIC PLASTIC PACKAGE (S)
0.189-0.197*
(4.801-5.004)
0.123 (3.12)
0.137 (3.48)
8
7 6
5
8
7
6
5
0.228-0.244
(5.791-6.197)
0.150-0.157**
(3.810-3.988)
0.090 (2.28)
0.102 (2.59)
1
2
3
4
1
2
3
4
0.010-0.020
(0.254-0.508)
x45°
0.053-0.069
(1.346-1.752)
0.004-0.010
(0.101-0.254)
0.008-0.010
(0.203-0.254)
0°-8 ° TYP
0.014-0.019
(0.355-0.483)
0.050
(1.270)
TYP
0.016-0.050
(0.406-1.270)
S(SO- 8 ) AMS DRW# 042293
*DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH
SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE
0.024(0.61)
0.063(1.60)
0.050(1.27)
**DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD
FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE
0.105(2.67)
0.213(5.41)
0.138 (3.50)
RECOMMENDED LAYOUT PATTERN
Advanced Monolithic Systems, Inc. www.advanced-monolithic.com Phone (925) 443-0722 Fax (925) 443-0723
相关型号：
©2020 ICPDF网 联系我们和版权申明