LM2622
Electrical Characteristics
(Continued)
Note 3:
The human body model is a 100 pF capacitor discharged through a 1.5kΩ resistor into each pin. The machine model is a 200pF capacitor discharged
directly into each pin.
Note 4:
All limits guaranteed at room temperature (standard typeface) and at temperature extremes (bold typeface). All room temperature limits are 100%
production tested. All limits at temperature extremes are guaranteed via correlation using standard Statistical Quality Control (SQC) methods. All limits are used to
calculate Average Outgoing Quality Level (AOQL).
Note 5:
Typical numbers are at 25˚C and represent the most likely norm.
Note 6:
Duty cycle affects current limit due to ramp generator.
Note 7:
Current limit at 0% duty cycle. See TYPICAL PERFORMANCE section for Switch Current Limit vs. V
IN
Note 8:
Bias current flows into FB pin.
Note 9:
Junction to ambient thermal resistance (no external heat sink) for the MSO8 package with minimal trace widths (0.010 inches) from the pins to the circuit.
See ’Scenario ’A’’ in the Power Dissipation section.
Note 10:
Junction to ambient thermal resistance for the MSO8 package with minimal trace widths (0.010 inches) from the pins to the circuit and approximately
0.0191 sq. in. of copper heat sinking. See ’Scenario ’B’’ in the Power Dissipation section.
Note 11:
Junction to ambient thermal resistance for the MSO8 package with minimal trace widths (0.010 inches) from the pins to the circuit and approximately
0.0465 sq. in. of copper heat sinking. See ’Scenario ’C’’ in the Power Dissipation section.
Note 12:
Junction to ambient thermal resistance for the MSO8 package with minimal trace widths (0.010 inches) from the pins to the circuit and approximately
0.2523 sq. in. of copper heat sinking. See ’Scenario ’D’’ in the Power Dissipation section.
Note 13:
Junction to ambient thermal resistance for the MSO8 package with minimal trace widths (0.010 inches) from the pins to the circuit and approximately
0.0098 sq. in. of copper heat sinking on the top layer and 0.0760 sq. in. of copper heat sinking on the bottom layer, with three 0.020 in. vias connecting the planes.
See ’Scenario ’E’’ in the Power Dissipation section.
Typical Performance Characteristics
Efficiency vs. Load Current
(V
OUT
= 8V, f
S
= 600 kHz)
Efficiency vs. Load Current
(V
OUT
= 8V, f
S
= 1.3 MHz)
10127326
10127325
Switch Current Limit vs. Temperature
(V
IN
= 3.3V, V
OUT
= 8V)
Switch Current Limit vs. V
IN
10127320
10127322
5
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