Preliminary
Absolute Maximum Ratings
RT9261B
Output Voltage -------------------------------------------------------------------------------------------------------- 8V
LX Pin Voltage --------------------------------------------------------------------------------------------------------- 8V
EN Pin Voltage
(1)
------------------------------------------------------------------------------------------------------
−
0.3 to V
OUT
+0.3V
LX Pin Output Current ----------------------------------------------------------------------------------------------- 400mA
Power Dissipation, P
D
@ T
A
= 25°C
SOT-89 ------------------------------------------------------------------------------------------------------------------ 0.5W
SOT-23-5 ---------------------------------------------------------------------------------------------------------------
0.25W
Package Thermal Resistance
SOT-89,
θ
JC
------------------------------------------------------------------------------------------------------------ 100° C/W
SOT-89,
θ
JA
------------------------------------------------------------------------------------------------------------ 300° C/W
SOT-23-5,
θ
JA
---------------------------------------------------------------------------------------------------------- 250° C/W
Operating Temperature Range -------------------------------------------------------------------------------------
−
20 to +85°C
Storage Temperature Range ---------------------------------------------------------------------------------------
−
65°C to 150°C
Lead Temperature (Soldering, 10 sec.) -------------------------------------------------------------------------- 260°C
Notes: (1) Applicable to RT9261B-xxCB
Electrical Characteristics
Parameter
Output Voltage Accuracy
Input Voltage
Start-up Voltage
Hold-on Voltage
Input Current 1
(1) (2)
(Refer to Figure 1)
Symbol
ΔV
OUT
V
IN
V
ST
V
HO
I
OUT
= 1mA, V
IN
: 0
→
2V
I
OUT
= 1mA, V
IN
: 2
→
0V
To be measured at V
IN
in
continuous switching
To be measured at V
OUT
in
switch off condition
Test Conditions
Min
-2
--
--
0.7
--
--
--
--
--
120
160
--
140
140
65
--
LX switch on
0.65
Typ
--
--
0.8
--
24
36
6.5
18
20
--
--
--
190
190
75
80
0.8
Max Units
+2
7
1
--
36
45
10
36
45
--
--
0.5
240
320
85
--
1.0
mA
μA
kHz
kHz
%
%
V
%
V
V
V
μA
μA
V
OUT
≤
3.5V
(1)
(2)
3.5V
<
V
OUT
≤
5V
Input Current 2
Input Current 3
V
OUT
≤
3.5V
(1)
3.5V
<
V
OUT
≤
5V
LX Switching Current
LX Leakage Current
Maximum Oscillator Frequency
Oscillator Duty Cycle
Efficiency
V
LX
Voltage Limit
Notes:
(2)
To be measured at V
IN
in no
load (guaranteed by I
1
and I
2
)
I
SWITCHING
V
LX
= 0.4V
I
LEAKAGE
F
MAX
D
OSC
V
LX
= 6V
V
OUT
= 2.5V to 5V
V
OUT
= 1.5V to 2.4V
On (V
LX
“L”) side
μA
V
OUT
≤
3.5V
(1)
(2)
3.5V
<
V
OUT
≤
5V
(1) V
IN
= 1.8V, V
SS
= 0V, I
OUT
= 1mA, Topt = 25° C, and use External Circuit of Typical Application
(2) V
IN
= 3V, V
SS
= 0V, I
OUT
= 1mA, Topt= 25°C, and External Circuit of Typical Application
DS9261B-12 March 2007
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