LTC4252A-1CMS#TRPBF Linear Technology, LTC4252A-1CMS#TRPBF Datasheet - Page 14

• Manufacturer Part Number: LTC4252A-1CMS#TRPBF
• Description: IC CNTRLR HOTSWAP NEGVOLT 10MSOP
• Manufacturer: Linear Technology
• Type: Hot-Swap Controllerr

Specifications of LTC4252A-1CMS#TRPBF

• Applications: General Purpose
• Internal Switch(s): No
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 10-TFSOP, 10-MSOP (0.118", 3.00mm Width)
• Family Name: LTC4252A-1
• Package Type: MSOP
• Operating Temperature (min): 0C
• Operating Temperature (max): 70C
• Operating Temperature Classification: Commercial
• Product Depth (mm): 3mm
• Product Height (mm): 0.86mm
• Product Length (mm): 3mm
• Mounting: Surface Mount
• Pin Count: 10
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

APPLICATIONS INFORMATION
LTC4252-1/LTC4252-2
LTC4252A-1/LTC4252A-2
SHUNT REGULATOR
A fast responding shunt regulator clamps the V
(VZ). Power is derived from –48RTN by an external current
limiting resistor, R
supply transients and contributes a short delay at start-up.
To meet creepage requirements R
more series connected units. This introduces a wider total
spacing than is possible with a single component while at
the same time ballasting the potential across the gap under
each resistor. The LTC4252 is fundamentally a low voltage
device that operates with –48V as its reference ground. To
further protect against arc discharge into its pins, the area
in and around the LTC4252 and all associated components
should be free of any other planes such as chasis ground,
return, or secondary-side power and ground planes.
V
accomodate external loading such as the PWRGD opto-
coupler shown in Figure 23. As an alternative to running
higher current, simply buffer V
as shown in Figure 3. Another method shown in Figure
19 cascodes the PWRGD output.
V
package, and is tested to survive a 100μs, 100mA pulse. To
protect V
clamp V
V
14
IN
IN
EE
may be biased with additional current up to 30mA to
is rated handle 30mA within the thermal limits of the
and all V
IN
IN
to V
against damage from higher amplitude spikes,
EE
-referred components to the sense resistor
EE
IN
with a 13V Zener diode. Star connect
(SHORT PIN)
. A 1μF decoupling capacitor, C
–48RTN
–48RTN
–48V
* M0C207
Q2: MMBT5551LT1
4.75k
38.3k
Figure 3. – 48V/2.5A Application with Different Input Operating Range
432k
1%
1%
1%
R1
R2
R3
IN
IN
with an emitter follower
may be split into two or
C2
10nF
**DIODES, INC
†
RECOMMENDED FOR HARSH ENVIRONMENTS
C
330nF
IN
T
pin to 13V
10
IN
9
8
3
OV
TIMER
UV
SS
filters
C
68nF
SS
LTC4252-1
V
V
EE
IN
5
1
R
10k
1/2W
IN
Kelvin terminal as illustrated in Figure 3, keeping trace
lengths between V
INTERNAL UNDERVOLTAGE LOCKOUT (UVLO)
A hysteretic comparator, UVLO, monitors V
age. The thresholds are defined by V
V
(V
UVLO function at V
UV/OV pin(s). These are completely separate functions.
UV/OV COMPARATORS (LTC4252)
An UV hysteretic comparator detects undervoltage condi-
tions at the UV pin, with the following thresholds:
An OV hysteretic comparator detects overvoltage condi-
tions at the OV pin, with the following thresholds:
The UV and OV trip point ratio is designed to match the
standard telecom operating range of 43V to 82V when con-
nected together as in the typical application. A divider (R1,
R2) is used to scale the supply voltage. Using R1 = 402k
PWRGD
SENSE
DRAIN
LKH
GATE
LKO
UV low-to-high (V
UV high-to-low (V
OV low-to-high (V
OV high-to-low (V
D
DDZ13B
IN
. When V
†
– V
2
7
6
4
**
LKH
IN
) it is disabled and GATE is pulled low. The
22k
C
1μF
R4
IN
rises above V
R
IN
D
, C
1M
IN
Q2
UVHI
UVLO
OVHI
OVLO
R5
2.2k
IN
R
10Ω
should not be confused with the
C
C
18nF
100μF
, D
C
) = 3.225V
) = 6.150V
) = 2.925V
) = 5.550V
425212 F03
*
C
IN
L
+
LKO
and V
Q1
IRF530S
R
0.02Ω
the chip is enabled; below
S
EN
LOAD
EE
LKO
as short as possible.
and its hysteresis,
IN
for undervolt-
425212fc