参数资料
型号: TOP244PN-TL
厂商: POWER INTEGRATIONS INC
元件分类: 稳压器
英文描述: 2.16 A SWITCHING REGULATOR, 140 kHz SWITCHING FREQ-MAX, PDIP7
封装: PLASTIC, DIP-8/7
文件页数: 18/52页
文件大小: 457K
代理商: TOP244PN-TL
TOP242-250
25
H
9/02
Processor Controlled Supply Turn On/Off
A low cost momentary contact switch can be used to turn the
TOPSwitch-GX power on and off under microprocessor
control that may be required in some applications such as
printers. The low power remote off feature allows an elegant
implementation of this function with very few external
components as shown in Figure 45. Whenever the push button
momentary contact switch P1 is closed by the user, the
optocoupler U3 is activated to inform the microprocessor of
this action. Initially, when the power supply is off (M pin is
floating), closing of P1 turns the power supply on by shorting
the M pin of the TOPSwitch-GX to SOURCE through a diode
(remote on). When the secondary output voltage VCC is
established, the microprocessor comes alive and recognizes that
the switch P1 is closed through the switch status input that is
driven by the optocoupler U3 output. The microprocessor then
sends a power supply control signal to hold the power supply
in the on-state through the optocoupler U4. If the user presses
the switch P1 again to command a turn off, the microprocessor
detects this through the optocoupler U3 and initiates a shut-
down procedure that is product specific. For example, in the
case of the inkjet printer, the shutdown procedure may include
safely parking the print heads in the storage position. In the
case of products with a disk drive, the shutdown procedure
may include saving data or settings to the disk. After the shut-
down procedure is complete, when it is safe to turn off the
power supply, the microprocessor releases the M pin by
turning the optocoupler U4 off. If the manual switch and the
optocouplers U3 and U4 are not located close to the M pin, a
capacitor C
M may be needed to prevent noise coupling to the
pin when it is open.
The power supply could also be turned on remotely through a
local area network or a parallel or serial port by driving the
optocoupler U4 input LED with a logic signal. Sometimes it is
easier to send a train of logic pulses through a cable (due to AC
coupling of cable, for example) instead of a DC logic level as
a wake up signal. In this case, a simple RC filter can be used to
generate a DC level to drive U4 (not shown in Figure 45). This
remote on feature can be used to wake up peripherals such as
printers, scanners, external modems, disk drives, etc., as needed
from a computer. Peripherals are usually designed to turn off
automatically if they are not being used for a period of time, to
save power.
U1
U2
U4
U3
CM
P1
P1 Switch
Status
Power
Supply
ON/OFF
Control
External
Wake-up
Signal
PI-2561-033001
VCC
(+5 V)
RETURN
CONTROL
MICRO
PROCESSOR/
CONTROLLER
LOGIC
INPUT
LOGIC
OUTPUT
High Voltage
DC Input
+
-
TOPSwitch-GX
DM
SF
C
1N4148
U4
LTV817A
6.8 k
1 nF
100 k
6.8 k
U3
LTV817A
27 k
1N4148
47 F
Figure 45. Remote ON/OFF using Microcontroller.
相关PDF资料
PDF描述
TOP250YN-TL 10.08 A SWITCHING REGULATOR, 140 kHz SWITCHING FREQ-MAX, PZFM6
TOP244RN-TL 2.16 A SWITCHING REGULATOR, 140 kHz SWITCHING FREQ-MAX, PSSO6
TOP244Y-TL 2.16 A SWITCHING REGULATOR, 140 kHz SWITCHING FREQ-MAX, PZFM6
TOP246Y-TL 4.32 A SWITCHING REGULATOR, 140 kHz SWITCHING FREQ-MAX, PZFM6
TOP245YN-TL 2.88 A SWITCHING REGULATOR, 140 kHz SWITCHING FREQ-MAX, PZFM6
相关代理商/技术参数
参数描述
TOP244P-TL 制造商:POWERINT 制造商全称:Power Integrations, Inc. 功能描述:TOPSwitch-GX Family Extended Power, Design Flexible, EcoSmart, Integrated Off-line Switcher
TOP244R 制造商:POWERINT 制造商全称:Power Integrations, Inc. 功能描述:TOPSwitch-GX Family Extended Power, Design Flexible, EcoSmart, Integrated Off-line Switcher
TOP244R- 制造商:POWERINT 制造商全称:Power Integrations, Inc. 功能描述:TOPSwitch-GX Family Extended Power, Design Flexible, EcoSmart, Integrated Off-line Switcher
TOP244RN- 制造商:POWERINT 制造商全称:Power Integrations, Inc. 功能描述:TOPSwitch-GX Family Extended Power, Design Flexible, EcoSmart, Integrated Off-line Switcher
TOP244RN-TL 制造商:POWERINT 制造商全称:Power Integrations, Inc. 功能描述:TOPSwitch-GX Family Extended Power, Design Flexible, EcoSmart, Integrated Off-line Switcher