RT2855A/B
Parameter
R
DS(ON)
Switch On
Resistance
Current Limit
Current Limit
Thermal Shutdown
Thermal Shutdown Threshold
On-Time Timer Control
On-Time
Minimum Off-Time
Soft-Start
SS Charge Current
SS Discharge Current
UVLO
UVLO Threshold
Hysteresis
Power Good
PGOOD Threshold
PGOOD Sink Current
OVP Trip Threshold
OVP Prop Delay
UVP Trip Threshold
UVP Hysteresis
UVP Prop Delay
UVP Enable Delay
t
UVPEN
Relative to Soft-Start Time
V
FB
Rising
V
FB
Falling
PGOOD = 0.5V
OVP Detect
85
--
2.5
114
--
65
--
--
--
90
85
5
120
5
70
10
250
t
SS
x 1.7
95
--
--
126
--
75
--
--
--
%
mA
%
s
%
s
ms
Wake Up V
REG5
3.6
0.18
3.85
0.35
4.1
0.47
V
V
SS
= 0V
V
SS
= 0.5V (Latch Mode)
V
SS
= 0.5V (Hiccup Mode)
5
0.1
--
6
0.2
0.5
7.5
--
--
A
mA
A
t
ON
t
OFF(MIN)
V
IN
= 12V, V
OUT
= 1.05V
V
FB
= 0.7V, T
A
= 25C
--
--
135
260
--
310
ns
ns
T
SD
Shutdown Temperature
--
--
150
20
--
--
Thermal Shutdown Hysteresis
T
SD
C
I
LIM
5
6
7
A
High Side
Low Side
R
DS(ON)_H
R
DS(ON)_L
T
A
= 25C (V
BOOT
V
SW
) = 5.5V
T
A
= 25C
--
--
70
30
--
--
m
Symbol
Test Conditions
Min
Typ
Max
Unit
Output Under Voltage and Over Voltage Protection
Note 1.
Stresses beyond those listed
“Absolute
Maximum Ratings” may cause permanent damage to the device. These are
stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in
the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions may
affect device reliability.
Note 2.
θ
JA
is measured at T
A
= 25°C on a high effective thermal conductivity four-layer test board per JEDEC 51-7.
θ
JC
is
measured at the exposed pad of the package.
Note 3.
The device is not guaranteed to function outside its operating conditions.
Copyright
©
2015 Richtek Technology Corporation. All rights reserved.
is a registered trademark of Richtek Technology Corporation.
DS2855A/B-01
September 2015
www.richtek.com
9
RICHTEK [ RICHTEK TECHNOLOGY CORPORATION ]
