参数资料
型号: CPC7591MC
厂商: CLARE INC
元件分类: 通信及网络
中文描述: SPECIALTY TELECOM CIRCUIT, PDSO16
封装: MLP-16
文件页数: 3/17页
文件大小: 391K
代理商: CPC7591MC
CPC7591
R01
www.clare.com
11
2.2.2 Hot Plug and Power Up Circuit Design
Considerations
There are six possible start up scenarios that can
occur during power up. They are:
1.
All inputs defined at power up & LATCH = 0
2.
All inputs defined at power up & LATCH = 1
3.
All inputs defined at power up & LATCH = Z
4.
All inputs not defined at power up & LATCH = 0
5.
All inputs not defined at power up & LATCH = 1
6.
All inputs not defined at power up & LATCH = Z
Under all of the start up situations listed above the
CPC7591 will hold all of it’s switches in the all-off state
during power up. When VDD requirements have been
satisfied the LCAS will complete it’s start up procedure
in one of three conditions.
For start up scenario 1 the CPC7591 will transition
from the all-off state to the state defined by the inputs
when VDD is valid.
For start up scenarios 2, 3, 5, and 6 the CPC7591 will
power up in the all-off state and remain there until the
LATCH pin is pulled low. This allows for an indefinite
all-off state for boards inserted into a powered system
but are not configured for service or boards that need
to wait for other devices to be configured first.
Start up scenario 4 will start up with all switches in the
all-off state but upon the acceptance of a valid VDD the
LCAS will revert to either the talk state or the ringing
state and there after may randomly change states
based on input pin leakage currents and loading.
Because the LCAS state after power up can not be
predicted with this start up condition it should never be
utilized.
On designs that do not wish to individually control the
LATCH pins of multiple-port cards it is possible to bus
many (or all) of the LATCH pins together to create a
single board level input enable control.
2.3 Switch Logic
2.3.1 Start-up
The CPC7591 uses smart logic to monitor the VDD
supply. Any time the VDD is below an internally set
threshold, the smart logic places the control logic to
the all-off state. An internal pullup on the LATCH pin
locks the CPC7591 in the all-off state following
start-up until the LATCH pin is pulled down to a logic
low. Prior to the assertion of a logic low at the LATCH
pin, the switch control inputs must be properly
conditioned.
2.3.2 Switch Timing
The CPC7591 provides, when switching from the
ringing state to the talk state, the ability to control the
release timing of the ringing switches SW3 and SW4
relative to the state of the break switches SW1 and
SW2 using simple TTL logic-level inputs. The two
available techniques are referred to as
make-before-break and break-before-make operation.
When the switch contacts of SW1 and SW2 are closed
(made) before the ringing switch contacts of SW3 and
SW4 are opened (broken), this is referred to as
make-before-break operation. Break-before-make
operation occurs when the ringing contacts of SW3
and SW4 are opened (broken) before the switch
contacts of SW1 and SW2 are closed (made). With
the CPC7591, make-before-break and
break-before-make operations can easily be
accomplished by applying the proper sequence of TTL
logic-level inputs to the device.
2.3.3 Make-Before-Break Operation
To use make-before-break operation, change the logic
inputs from the ringing state directly to the talk state.
Application of the talk state opens the ringing return
switch, SW3, as the break switches SW1 and SW2
close. The ringing switch, SW4, remains closed until
the next zero-crossing of the ringing current. While in
the make-before-break state, ringing potentials in
excess of the CPC7591 protection circuitry thresholds
will be diverted away from the SLIC. This operational
sequence is shown below in the “Make-Before-Break
相关PDF资料
PDF描述
CPC7591BCTR
CPC7591MCTR
CPC7595ZC
CPC7595BBTR
CPC7595ZCTR
相关代理商/技术参数
参数描述
CPC7591MCTR 功能描述:固态继电器-PCB安装 4-pole, high hold current, MLP LCAS, T/R RoHS:否 制造商:Omron Electronics 控制电压范围: 负载电压额定值:40 V 负载电流额定值:120 mA 触点形式:1 Form A (SPST-NO) 输出设备:MOSFET 封装 / 箱体:USOP-4 安装风格:SMD/SMT
CPC7592 制造商:CLARE 制造商全称:Clare, Inc. 功能描述:Line Card Access Switch
CPC7592_12 制造商:IXYS 制造商全称:IXYS Corporation 功能描述:Line Card Access Switch
CPC7592BA 功能描述:固态继电器-PCB安装 6-pole SOIC LCAS RoHS:否 制造商:Omron Electronics 控制电压范围: 负载电压额定值:40 V 负载电流额定值:120 mA 触点形式:1 Form A (SPST-NO) 输出设备:MOSFET 封装 / 箱体:USOP-4 安装风格:SMD/SMT
CPC7592BATR 功能描述:固态继电器-PCB安装 6-pole SOIC LCAS, T/R RoHS:否 制造商:Omron Electronics 控制电压范围: 负载电压额定值:40 V 负载电流额定值:120 mA 触点形式:1 Form A (SPST-NO) 输出设备:MOSFET 封装 / 箱体:USOP-4 安装风格:SMD/SMT