參數(shù)資料
型號(hào)： SP3238EECY-L
元件分類(lèi)： RS-232
英文描述： 5V High-Speed RS-232 Transceivers with 0.1uF Capacitors
中文描述： 5V的高速RS - 232收發(fā)器與0.1uF電容
文件頁(yè)數(shù)： 15/20頁(yè)
文件大?。?/td> 248K
代理商： SP3238EECY-L
15
Date: 02/24/05
SP3238EE Intelligent +3.0V to +5.5V RS-232 Transceiver
Copyright 2005 Sipex Corporation
AUTO ON-LINE
Circuitry
The SP3238EE
device has a patent pending
AUTO ON-LINE
circuitry on board that saves
power in applications such as laptop computers,
palmtop (PDA) computers, and other portable
systems.
The SP3238EE device incorporates an
AUTO ON-LINE
circuit that automatically
enables itself when the external transmitters are
enabled and the cable is connected. Conversely,
the
AUTO ON-LINE
circuit also disables
most of the internal circuitry when the device is
not being used and goes into a standby mode
where the device typically draws 1
μ
A. This
function is externally controlled by the ONLINE
pin. When this pin is tied to a logic LOW, the
AUTO ON-LINE
function is active. Once
active, the device is enabled until there is no
activity on the receiver inputs. The receiver
input typically sees at least +3V, which are
generated from the transmitters at the other end
of the cable with a +5V minimum. When the
external transmitters are disabled or the cable is
disconnected, the receiver inputs will be pulled
down by their internal 5k
resistors to ground.
When this occurs over a period of time, the
internal transmitters will be disabled and the
device goes into a shutdown or standby mode.
When ONLINE is HIGH, the
AUTO ON-
LINE
mode is disabled.
The
AUTO ON-LINE
circuit has two stages:
1) Inactive Detection
2) Accumulated Delay
The first stage, shown in Figure 17, detects an
inactive input. A logic HIGH is asserted on
R
INACT if the cable is disconnected or the
external transmitters are disabled. Otherwise,
R
INACT will be at a logic LOW. This circuit
is duplicated for each of the other receivers.
The second stage of the
AUTO ON-LINE
circuitry, shown in Figure 18, processes all the
receiver's R
INACT signals with an accumu-
lated delay that disables the device to a 1
μ
A
supply current.
The STATUS pin goes to a logic LOW when the
cable is disconnected or when the external trans-
mitters are disabled.
When the drivers or internal charge pump are
disabled, the supply current is reduced to 1
μ
A.
This can commonly occur in hand-held or
portable applications where the RS-232 cable is
disconnected or the RS-232 drivers of the
connected peripheral are turned off.
The
AUTO ON-LINE
mode can be disabled
by the SHUTDOWN pin. If this pin is a logic
LOW, the
AUTO ON-LINE
function will not
operate regardless of the logic state of the
ONLINE pin.
Table 2 summarizes the logic of
the
AUTO ON-LINE
operating modes and
the truth table logic of the driver and receiver
outputs.
The STATUS pin outputs a logic LOW signal
when there is no valid RS-232 signal present on
any receiver input. This pin goes to a
logic HIGH when the external transmitters are
enabled and the cable is connected.
When the SP3238E
device is shut down, the
charge pump is turned off. V+ charge pump
output decays to V
, the V- output decays to
GND. The decay time will depend on the size of
capacitors used for the charge pump. Once in
shutdown, the time required to exit the shut
down state and have valid V+ and V- levels is
typically 200ms.
For easy programming, the STATUS pin can be
used to indicate DTR or a Ring Indicator signal.
Tying ONLINE and SHUTDOWN together
will bypass the
AUTO ON-LINE
circuitry so
this connection acts like a shutdown input pin.
相關(guān)PDF資料
PDF描述
SP3238E Intelligent +3.0V to +5.5V RS-232 Transceivers(智能+3.0V 至 +5.5V RS-232收發(fā)器（5發(fā)3收）)
SP3238ECA 5V High-Speed RS-232 Transceivers with 0.1uF Capacitors
SP3238ECY 2.7V-5.5V, 12 bit, 3MSPS, Serial ADC 6-SOT-23 -40 to 125
SP3238EEY 5V High-Speed RS-232 Transceivers with 0.1uF Capacitors
SP3238EEA 5V High-Speed RS-232 Transceivers with 0.1uF Capacitors
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
SP3238EECY-L/TR 制造商:SIPEX 制造商全稱(chēng):Sipex Corporation 功能描述:Intelligent +3.0V to +5.5V RS-232 Transceiver
SP3238EEEA 制造商:SIPEX 制造商全稱(chēng):Sipex Corporation 功能描述:Intelligent +3.0V to +5.5V RS-232 Transceiver
SP3238EEEA/TR 制造商:SIPEX 制造商全稱(chēng):Sipex Corporation 功能描述:Intelligent +3.0V to +5.5V RS-232 Transceiver
SP3238EEEA-L 制造商:SIPEX 制造商全稱(chēng):Sipex Corporation 功能描述:Intelligent +3.0V to +5.5V RS-232 Transceiver
SP3238EEEA-L/TR 制造商:SIPEX 制造商全稱(chēng):Sipex Corporation 功能描述:Intelligent +3.0V to +5.5V RS-232 Transceiver
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。

采購(gòu)需求

(若只采購(gòu)一條型號(hào)，填寫(xiě)一行即可)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

*型號(hào) *數(shù)量 廠(chǎng)商 批號(hào) 封裝
添加更多采購(gòu)

我的聯(lián)系方式

*
*
*