MAX3232CSE+ Datasheet

  • MAX3232CSE+

  • TRANSCEIVER RS-232, 3232, SOIC16; Interface Type:RS-232; No....

  • 752.80KB

  • 17页

  • Maxim   Maxim

扫码查看芯片数据手册

上传产品规格书

PDF预览

3.0V to 5.5V, Low-Power, up to 1Mbps, True RS-232
Transceivers Using Four 0.1碌F External Capacitors
MAX3222/MAX3232/MAX3237/MAX3241
RS-232 Receivers
V
CC
V
CC
Rx
PROTECTION
DIODE
UART
Tx
GND
SHDN = GND
PREVIOUS
RS-232
The receivers convert RS-232 signals to CMOS-logic out-
put levels. The MAX3222/MAX3237/MAX3241 receivers
have inverting three-state outputs. In shutdown, the
receivers can be active or inactive (Table 1).
The complementary outputs on the MAX3237 (R1OUTB)
and the MAX3241 (R1OUTB, R2OUTB) are always active,
regardless of the state of
EN
or
SHDN.
This allows for
Ring Indicator applications without forward biasing other
devices connected to the receiver outputs. This is ideal
for systems where V
CC
is set to 0V in shutdown to
accommodate peripherals, such as UARTs (Figure 2).
5k
MAX3222/MAX3237/MAX3241
Shutdown Mode
Supply current falls to less than 1碌A in shutdown mode
(SHDN = low). When shut down, the device鈥檚 charge
pumps are turned off, V+ is pulled down to V
CC
, V- is
pulled to ground, and the transmitter outputs are dis-
abled (high impedance). The time required to exit shut-
down is typically 100碌s, as shown in Figure 3. Connect
SHDN
to V
CC
if the shutdown mode is not used.
SHDN
has no effect on R_OUT or R_OUTB.
a)
OLDER RS-232: POWERED-DOWN UART DRAWS CURRENT FROM
ACTIVE RECEIVER OUTPUT IN SHUTDOWN.
V
CC
TO
碌P
LOGIC
TRANSITION
DETECTOR
MAX3222/MAX3237/MAX3241
Enable Control
The inverting receiver outputs (R_OUT) are put into a
high-impedance state when
EN
is high. The complemen-
tary outputs R1OUTB and R2OUTB are always active,
regardless of the state of
EN
and
SHDN
(Table 1).
EN
has no effect on T_OUT.
MAX3237
MAX3241
R1OUTB
V
CC
Rx
PROTECTION
DIODE
UART
Tx
GND
T1IN
SHDN = GND
R1OUT
EN = V
CC
5k
T1OUT
R1IN
__________Applications Information
Capacitor Selection
The capacitor type used for C1鈥揅4 is not critical for
proper operation; polarized or nonpolarized capacitors
can be used. The charge pump requires 0.1碌F capaci-
tors for 3.3V operation. For other supply voltages, refer to
Table 2 for required capacitor values. Do not use values
lower than those listed in Table 2. Increasing the capaci-
tor values (e.g., by a factor of 2) reduces ripple on the
transmitter outputs and slightly reduces power consump-
tion. C2, C3, and C4 can be increased without changing
C1鈥檚 value. However, do not increase C1 without also
increasing the values of C2, C3, and C4, to maintain the
proper ratios (C1 to the other capacitors).
When using the minimum required capacitor values,
make sure the capacitor value does not degrade exces-
sively with temperature. If in doubt, use capacitors with a
higher nominal value. The capacitor鈥檚 equivalent series
resistance (ESR), which usually rises at low tempera-
tures, influences the amount of ripple on V+ and V-.
b)
NEW MAX3237/MAX3241: EN SHUTS DOWN RECEIVER OUTPUTS (EXCEPT FOR
B OUTPUTS), SO NO CURRENT FLOWS TO UART IN SHUTDOWN. B OUTPUTS
INDICATE RECEIVER ACTIVITY DURING SHUTDOWN WITH EN HIGH.
Figure 2. Detection of RS-232 Activity when the UART and
Interface are Shut Down; Comparison of MAX3237/MAX3241
(b) with Previous Transceivers (a).
8
_______________________________________________________________________________________

MAX3232CSE+ 产品属性

  • Lead (SnPb) Finish for COTSObsolescence Mitigation Program

  • 50

  • 集成电路 (IC)

  • 接口 - 驱动器,接收器,收发器

  • -

  • 收发器

  • 2/2

  • RS232

  • 3 V ~ 5.5 V

  • 表面贴装

  • 16-SOIC(0.154",3.90mm 宽)

  • 16-SOIC

  • 管件

MAX3232CSE+相关型号PDF文件下载

您可能感兴趣的PDF文件资料

热门IC型号推荐

扫码下载APP,
一键连接广大的电子世界。

在线人工客服

买家服务:
卖家服务:
技术客服:

0571-85317607

网站技术支持

13606545031

客服在线时间周一至周五
9:00-17:30

关注官方微信号,
第一时间获取资讯。

建议反馈
返回顶部

建议反馈

联系人:

联系方式:

按住滑块,拖拽到最右边
>>
感谢您向阿库提出的宝贵意见,您的参与是维库提升服务的动力!意见一经采纳,将有感恩红包奉上哦!