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Symbol
Parameter
Conditions
Min
Typ
Max
Units
OSCILLATOR (RT)
f
SW
Switching Frequency
R
T
= 36 k
Ω
164
207
250
kHz
R
T
= 12 k
Ω
525
597
669
V
RT-SYNC
Sync Threshold
3.5
V
PWM COMPARATOR
V
CP-BASE
COMP to PWM Offset - No
Slope Compensation
750
900
1050
mV
SLOPE COMPENSATION (SLOPE)
Δ
V
CP
Slope Compensation
Amplitude
Additional COMP to PWM Offset -
SLOPE sinking 100 µA
85
mV
CURRENT LIMIT (IS)
V
LIM
Current Limit Threshold
215
245
275
mV
V
LIM
Delay to Output
35
75
ns
t
ON-MIN
Leading Edge Blanking Time
140
240
340
HIGH SIDE TRANSCONDUCTANCE AMPLIFIER
Input Bias Current
10
µA
Transconductance
20
mA/V
Input Offset Current
-1.5
0
1.5
µA
Input Offset Voltage
-5
0
5
mV
Transconductance
Bandwidth
I
CSH
= 100 µA
500
kHz
GATE DRIVER (GATE)
R
SRC-GATE
GATE Sourcing Resistance
GATE = High
2.0
6.0
Ω
R
SNK-GATE
GATE Sinking Resistance
GATE = Low
1.3
4.5
UNDER-VOLTAGE LOCKOUT and DIM INPUT (nDIM)
V
TH-nDIM
nDIM / UVLO Threshold
1.185
1.240
1.285
V
I
HYS-nDIM
nDIM Hysteresis Current
13
20
27
µA
DIM DRIVER (DDRV)
R
SRC-DDRV
DDRV Sourcing Resistance
DDRV = High
13.5
30.0
Ω
R
SNK-DDRV
DDRV Sinking Resistance
DDRV = Low
3.5
10.0
nDIM rising to DDRV rising
700
ns
nDIM rising to DDRV falling
360
SOFT-START (SS)
I
SS
Soft-start current
10
µA
THERMAL CONTROL
V
S
V
S
Voltage
I
VS
= 0A
2.40
2.45
2.50
V
I
VS
= 1 mA
TREF input bias current
V
TREF
= 1.5V
V
TSENSE
= 1.5V
0.1
µA
TSENSE Input Bias Current V
TREF
= 1.5V
V
TSENSE
= 1.5V
0.1
I
TGAIN-MAX
TGAIN Maximum Sourcing
Current
V
TGAIN
= 2V
200
600
I
TF
CSH Current with High-side
Amplifier Disabled
R
TGAIN
= 10
k
Ω
V
TREF
= 1.5V
V
TSENSE
= 0.5V
100
V
TREF
= 1.5V
V
TSENSE
= 1.4V
10
V
TREF
= 1.5V
V
TSENSE
= 1.5V
2
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LM3424