参数资料
型号: LTC4252-1IMS#PBF
厂商: Linear Technology
文件页数: 15/36页
文件大小: 328K
描述: IC CNTRLR HOTSWAP NEGVOLT 10MSOP
标准包装: 50
类型: 热交换控制器
应用: 通用
内部开关:
工作温度: -40°C ~ 85°C
安装类型: 表面贴装
封装/外壳: 10-TFSOP,10-MSOP(0.118",3.00mm 宽)
供应商设备封装: 10-MSOP
包装: 管件
LTC4252-1/LTC4252-2
LTC4252A-1/LTC4252A-2
15
425212fe
For more information www.linear.com/LTC4252-1
applicaTions inForMaTion
and R2 = 32.4k gives a typical operating range of 43.2V
to 82.5V . The undervoltage shutdown and overvoltage
recovery thresholds are then 39.2V and 74.4V . 1% divider
resistors are recommended to preserve threshold accuracy.
The R1-R2 divider values shown in the Typical Application
set a standing current of slightly more than 100礎 and
define an impedance at UV/OV of 30k? In most applica-
tions, 30k?impedance coupled with 300mV UV hysteresis
makes the LTC4252 insensitive to noise. If more noise
immunity is desired, add a 1nF to 10nF filter capacitor
from UV/OV to V
EE
.
Separate UV and OV pins are available in the 10-pin MS
package and can be used for a different operating range
such as 35.5V to 76V as shown in Figure 3. Other combi-
nations are possible with different resistor arrangements.
UV/OV COMPARATORS (LTC4252A)
A UV hysteretic comparator detects undervoltage condi-
tions at the UV pin, with the following thresholds:
   UV low-to-high (V
UV
) = 3.08V
   UV high-to-low (V
UV
 V
UVHST
) = 2.756V
An OV hysteretic comparator detects overvoltage condi-
tions at the OV pin, with the following thresholds:
   OV low-to-high (V
OV
) = 5.09V
   OV high-to-low (V
OV
 V
OVHST
) = 4.988V
The UV and OV trip point ratio is designed to match the
standard telecom operating range of 43V to 71V when
connected together as in Figure 2. A divider (R1, R2) is
used to scale the supply voltage. Using R1 = 390k and R2
= 30.1k gives a typical operating range of 43V to 71V . The
undervoltage shutdown and overvoltage recovery thresh-
olds are then 38.5V and 69.6V respectively. 1% divider
resistors are recommended to preserve threshold accuracy.
The R1-R2 divider values shown in Figure 2 set a standing
current of slightly more than 100礎 and define an impedance
at UV/OV of 28k? In most applications, 28k?impedance
coupled with 324mV UV hysteresis makes the LTC4252A
insensitive to noise. If more noise immunity is desired, add
a 1nF to 10nF filter capacitor from UV/OV to V
EE
.
The UV and OV pins can be used for a wider operat-
ing range such as 35.5V to 76V as shown in Figure 4.
Other combinations are possible with different resistor
arrangements.
UV/OV OPERATION
A low input to the UV comparator will reset the chip and pull
the GATE and TIMER pins low. A low-to-high UV transition
will initiate an initial timing sequence if the other interlock
425212 F04
48RTN
UV
OV
V
EE
V
IN
SENSE
SS
TIMER
GATE
PWRGD
DRAIN
LTC4252A-1
R1
464k
1%
R3
34k
1%
R2
10k
1%
C
T
0.68礔
C
SS
68nF
C
C
10nF
48V
R
S
0.02
Q1
IRF530S
R
C
10
R5
2.2k
Q2
R
IN
10k
1/2W
1
9
8
10
3
2
7
6
4
5
C2
10nF
C
IN
1礔
C
L
100礔
48RTN
(SHORT PIN)
+
R
D
 1M
LOAD
EN
R4
22k
*
* M0C207
Q2: MMBT5551LT1
**DIODES, INC
 
RECOMMENDED FOR HARSH ENVIRONMENTS
D
IN
 
DDZ13B
**
Figure 4. 48V/2.5A Application with Wider Input Operating Range
相关PDF资料
PDF描述
MAX8510EXK21+T IC REG LDO 2.1V .12A SC70-5
TDC106K050WSG-F CAP TANT 10UF 50V 10% RADIAL
R-783.3-1.0 CONV DC/DC 1A 3.3V OUT SIP VERT
MAX8510EXK29+T IC REG LDO 2.85V .12A SC70-5
V300C5H100BL CONVERTER MOD DC/DC 5V 100W
相关代理商/技术参数
参数描述
LTC4252-1IMSTR 制造商:LINER 制造商全称:Linear Technology 功能描述:Negative Voltage Hot Swap Controllers
LTC4252-1IMSTRPBF 制造商:LINER 制造商全称:Linear Technology 功能描述:Negative Voltage Hot Swap Controllers
LTC4252-2 制造商:LINER 制造商全称:Linear Technology 功能描述:Negative Voltage Hot Swap Controllers in SOT-23
LTC4252-2A 制造商:LINER 制造商全称:Linear Technology 功能描述:Negative Voltage Diode-OR Controller
LTC42522CMS 制造商:Linear Technology 功能描述: