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SLUS846 – SEPTEMBER 2008
ELECTRICAL CHARACTERISTICS
over operating free-air temperature range,
−40°C
< T
A
< 125°C, T
J
= T
A
, VCC = 12 V, GND = 0 V, R
RT
= 4.7 kΩ, R
DT
= 16.9
kΩ, C
VCC
= 1
µF,
(unless otherwise noted)
SYMBOL
Bias Supply (VCC)
VCC current, disabled
VCC current, enabled
VCC current, UVLO
UVLO turn-on threshold
V
UVLO
UVLO turn-off threshold
UVLO hysteresis
OVP turn-off threshold
V
OVP
OVP turn-on threshold
OVP hysteresis
Dead Time (DT)
T
DT
Oscillator
F
SW(min)
K
ICO
Minimum switching frequency at
GD1, GD2
Switching frequency gain/I (RT)
GD1, GD2 on time mismatching
F
SW_BM
Switching frequency starting burst
mode
Switching frequency to come out of
burst mode
F
SW(start)
Switching frequency at soft start
SS = 5 V
SS = 5 V
-40°C to 125°C
-20°C to 105°C
Measure at SS rising
Measured at SS falling
Measured at SS
Measured between SS (falling) and
GD2 (falling)
V
SS
= 0.5 V
V
SS
= 1.35 V
-40°C to 125°C
-20°C to 105°C
R
RT
= 4.7 kΩ, I
RT
= 0 to 1 mA
40.04
40.45
60
-50
300
280
122
125
1.1
0.85
0.15
250
-225
-5.5
500
-175
-5
350
330
142.5
142.5
1.2
1
41.70
41.70
80
43.36
42.95
100
50
400
380
162
160
1.3
1.1
0.35
750
-125
-4.5
ns
µA
V
kHz
kHz
Hz/µA
ns
Dead time
R
DT
= 16.9 kΩ
390
420
450
ns
SS = 0 V
SS = 5 V, C
GD1
= C
GD2
= 1 nF
VCC = 9 V
Measured at VCC rising
Measured at VCC falling
Measured at VCC
Measured at VCC rising
Measured at VCC falling
Measured at VCC
9.9
8.9
0.7 1
18
16
1.5
20
18
2
2.5
1
5
100
10.5
9.5
1.5
7.5
400
11.1
10.1
1.3
22
20
2.5
V
mA
µA
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNITS
External Disable/Soft Start
Enable threshold
Disable threshold
Disable hysteresis
Disable prop. delay
I
SS
Source current on ISS pin
Source current on ISS pin
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