EEWORLDEEWORLDEEWORLD

Part Number

Search

AS3842

Description
1 A SWITCHING CONTROLLER, 500 kHz SWITCHING FREQ-MAX, PDSO14
CategoryPower/power management   
File Size158KB,20 Pages
ManufacturerETC
Download Datasheet View All

AS3842 Overview

1 A SWITCHING CONTROLLER, 500 kHz SWITCHING FREQ-MAX, PDSO14

SEMICONDUCTOR
AS384x
Current Mode Controller
Description
The AS3842 family of control ICs provide pin-for-pin replacement of the
industry standard UC3842 series of devices. The devices are
redesigned to provide significantly improved tolerances in power sup-
ply manufacturing. The 2.5 V reference has been trimmed to 1.0%
tolerance. The oscillator discharge current is trimmed to provide guar-
anteed duty cycle clamping rather than specified discharge current.
The circuit is more completely specified to guarantee all parameters
impacting power supply manufacturing tolerances.
In addition, the oscillator and flip-flop sections have been enhanced to
provide additional performance. The R
T
/C
T
pin now doubles as a syn-
chronization input that can be easily driven from open collector/open
drain logic outputs. This sync input is a high impedance input and can
easily be used for externally clocked systems. The new flip-flop topol-
ogy allows the duty cycle on the AS3844/5 to be guaranteed between
49 and 50%. The AS3843/5 requires less than 0.5 mA of start-up cur-
rent over the full temperature range.
Features
¥
¥
¥
¥
¥
¥
¥
¥
2.5 V bandgap reference trimmed to
1.0% and temperature-compensated
Standard temperature range extended
to 105¡C
AS3842/3 oscillations trimmed for
precision duty cycle clamp
AS3844/5 have exact 50% max duty
cycle clamp
Advanced oscillator design simplifies
synchronization
Improved specs on UVLO and
hysteresis provide more predictable
start-up and shutdown
Improved 5 V regulator provides better
AC noise immunity
Guaranteed performance with current
sense pulled below ground
Top view
Pin Configuration Ñ
PDIP (N)
COMP
V
FB
I
SENSE
R
T
/C
T
1
2
3
4
8
7
6
5
8L SOIC (D8)
V
REG
V
CC
OUT
GND
COMP
V
FB
I
SENSE
R
T
/C
T
1
2
3
4
8
7
6
5
14L SOIC (D14)
V
REG
V
CC
OUT
GND
COMP
NC
V
FB
NC
I
SENSE
NC
R
T
/C
T
1
2
3
4
5
6
7
14
V
REG
13
NC
12
V
CC
11
V
C
10
OUT
9
8
PWR G
GND
Ordering Information
AS384X
Circuit Type:
Current Mode Controller (See Table A)
Package Style
D8 = 8 Pin Plastic SOIC
D14 = 14 Pin Plastic SOIC
N = 8 Pin Plastic DIP
D8
13
Packaging Option:
T = Tube
13 = Tape and Reel (13" Reel Dia)
Table A
Model
AS3842
AS3843
AS3844
AS3845
V
CC(min)
10
7.6
10
7.6
V
CC(on)
16
8.4
16
8.4
Duty Cycle
Typ.
97%
97%
49.5%
49.5%
I
CC
0.5 mA
0.3 mA
0.5 mA
0.3 mA
ASTEC Semiconductor
1
[Preparing for the 2011 National Competition], I have the final say on my own test questions!
Original intention of the activity : Recently, I often see people asking for help on how to solve the national competition questions in the forum. In fact, just like preparing for the college entrance...
EEWORLD社区 Electronics Design Contest
A balanced MLCC solution
[i=s]This post was last edited by paulhyde on 2014-9-15 09:23[/i] [font=Verdana]An X2Y capacitor is a balanced MLCC solution with three different electrical signal paths inside and four external conne...
dtcxn Electronics Design Contest
Please help, M4F232 about timer
When I initialized the program, as long as it executed the initialization part, the program would have problems. I blocked the initialization and the program was fine. The initialization function is v...
风神懿 Microcontroller MCU
ActiveSync cannot connect when customizing your system!
I would like to ask you, I used PB to burn the system, but activesync cannot connect the board to the PC. The phenomenon is that the PC shows: Unable to recognize USB device. What do you think is the ...
missingwind Embedded System
EEWORLD University ---- Altera and Micron lead the industry - FPGA and HMC interoperability demonstration
Altera and Micron lead the industry—FPGA and HMC interoperability demonstration : https://training.eeworld.com.cn/course/2104...
chenyy FPGA/CPLD
DSP Selection
The company has a product that needs a DSP chip with CAN UART ADC and preferably LCD driver. Does anyone know what chip is available?...
wanggq DSP and ARM Processors

EEWorld
subscription
account

EEWorld
service
account

Automotive
development
circle

Robot
development
community

Index Files: 1209  635  1731  1352  2825  25  13  35  28  57 
Datasheet   0 1 2 3 4 5 6 7 8 9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Room 1530, 15th Floor, Building B, No. 18 Zhongguancun Street, Haidian District, Beijing Telephone: (010) 82350740 Postal Code: 100190
Copyright © 2005-2026 EEWORLD.com.cn, Inc. All rights reserved 京ICP证060456号 京ICP备10001474号-1 电信业务审批[2006]字第258号函 京公网安备 11010802033920号