RT7253A
Absolute Maximum Ratings
(Note 1)
Supply Voltage, V
IN
-------------------------------------------------------------------------------------------------
−0.3V
to 18.7V
Input Voltage, SW ---------------------------------------------------------------------------------------------------
−0.3V
to (V
IN
+ 0.3V)
V
BOOT
- V
SW
-----------------------------------------------------------------------------------------------------------
−0.3V
to 6V
Other Pin Voltages -------------------------------------------------------------------------------------------------
−0.3V
to 6V
Power Dissipation, P
D
@ T
A
= 25°C
SOP-8 (Exposed Pad) --------------------------------------------------------------------------------------------- 1.333W
Package Thermal Resistance (Note 2)
SOP-8 (Exposed Pad),
θ
JA
---------------------------------------------------------------------------------------- 75°C/W
SOP-8 (Exposed Pad),
θ
JC
--------------------------------------------------------------------------------------- 15°C/W
Lead Temperature (Soldering, 10 sec.) ------------------------------------------------------------------------- 260°C
Junction Temperature ----------------------------------------------------------------------------------------------- 150°C
Storage Temperature Range --------------------------------------------------------------------------------------
−65°C
to 150°C
ESD Susceptibility (Note 3)
HBM (Human Body Mode) ---------------------------------------------------------------------------------------- 2kV
MM (Machine Mode) ------------------------------------------------------------------------------------------------ 200V
Recommended Operating Conditions
(Note 4)
Supply Voltage, V
IN
------------------------------------------------------------------------------------------------- 4.5V to 17V
Junction Temperature Range --------------------------------------------------------------------------------------
−40°C
to 125°C
Ambient Temperature Range --------------------------------------------------------------------------------------
−40°C
to 85°C
Electrical Characteristics
(V
IN
= 12V, T
A
= 25°C, unless otherwise specified)
Parameter
Shutdown Supply Current
Supply Current
Feedback Voltage
Error Amplifier
Transconductance
High Side Switch
On-Resistance
Low Side Switch
On-Resistance
High Side Switch Leakage
Current
Upper Switch Current Limit
Lower Switch Current Limit
COMP to Current Sense
Transconductance
Oscillation Frequency
Short Circuit Oscillation
Frequency
Maximum Duty Cycle
Minimum On Time
Symbol
V
EN
= 0V
Test Conditions
Min
--
--
0.788
--
--
--
Typ
0.5
0.8
0.8
940
120
120
0
5.1
1.3
4.7
340
100
93
100
Max
3
1.2
0.812
--
--
--
10
--
--
--
380
--
--
--
Unit
μA
mA
V
μA/V
mΩ
mΩ
μA
A
A
A/V
kHz
kHz
%
ns
V
EN
= 3 V, V
FB
= 0.9V
V
FB
G
EA
R
DS(ON)1
R
DS(ON)2
V
EN
= 0V, V
SW
= 0V
Min. Duty Cycle, V
BOOT
−V
SW
= 4.8V
From Drain to Source
G
CS
f
OSC1
f
OSC2
D
MAX
t
ON
V
FB
= 0V
V
FB
= 0.7V
4.5V
≤
V
IN
≤
17V
ΔI
C
= ± 10μA
--
--
--
--
300
--
--
--
To be continued
www.richtek.com
4
DS7253A-02 March 2011
RICHTEK [ RICHTEK TECHNOLOGY CORPORATION ]
