Symbol
ΔISS
VFB_F
Parameter
Conditions
Min
Typ
Max
3
Units
Difference Between SS1 and
SS2 Currents
µA
FB1 and FB2 Frequency Fold-
back Threshold
0.35
V
Thermal Characteristics
Typical Value
TSSOP LLP
Symbol
Description
Conditions
Unit
Junction-to-Ambient Thermal Mount package on a standard board (Note 5) and
θJA
θJC
28
3
26
Resistance (Note 4)
test per JESD51-7 standard.
°C/W
Junction-to-Case-Bottom
Thermal Resistance
2.8
Thermal Shutdown
Threshold
TSD
Junction temperature rises.
165
15
°C
Thermal Shutdown
Hysteresis
TSD_HYS
Junction temperature falls from above TSD.
Note 1: Absolute maximum ratings indicate limits beyond which damage to the device may occur. Operating Ratings are conditions under which the device is
intended to be functional, but specific performance is not guaranteed. For guaranteed performance limits and associated test conditions, see Electrical
Characteristics table.
Note 2: EN1 and EN2 pins should never be higher than VIN + 0.3V.
Note 3: The human body model is a 100pF capacitor discharged through a 1.5 kΩ resistor into each pin. Test method is per JESD-22-A114.
Note 4: Value is highly board-dependent. For comparison of package thermal performance only. Not recommended for prediction of junction temperature in real
applications. See THERMAL CONSIDERATIONS for more information.
Note 5: A standard board refers to a four-layer PCB with the size 4.5”x3”x0.063”. Top and bottom copper is 2 oz. Internal plane copper is 1 oz. For details refer
to JESD51-7 standard.
5
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