LM2574 Ver la hoja de datos (PDF) - Micrel
Número de pieza
componentes Descripción
Lista de partido
LM2574 Datasheet PDF : 8 Pages
| |||
LM2574
Electrical Characteristics
Symbol
Parameter
Device Parameters, Adjustable Regulator
IB
Feedback Bias Current
Condition
VOUT = 5V
Min Typ
50
Device Parameters, Fixed and Adjustable Regulators
fo
Oscillator Frequency
Note 8
VSAT
Saturation Voltage
IOUT = 0.5A(4)
47
52
42
0.8
DC
Max Duty Cycle (ON)
ICL
Current Limit
Note 5
Peak Current, tON ≤ 3µs(4)
IL
Output Leakage Current
VIN, Note 6, Output = 0V
Note 6, Output = –1V
IQ
Quiescent Current
Note 6
ISTBY
Standby Quiescent Current
ON/OFF Pin = 5V (OFF)
θJA
Thermal Resistance
N Package, Junction to Ambient(7)
On/Off Control, Fixed and Adjustable Regulators Test Circuit Figures 2, 3
VIH
ON/OFF Input Level
VOUT = 0V
VIL
ON/OFF Input Level
VOUT = 5V
93
98
0.7
1.0
0.65
7.5
5
50
85
2.2
1.4
2.4
1.2
IIH
ON/OFF Logic Current
IIL
ON/OFF Logic Current
ON/OFF = 5V (OFF)
ON/OFF = 0V (ON)
Notes:
4. Output (pin 2) sourcing current. No diode, inductor, or capacitor connected to input.
5. Feedback (pin 4) removed from output and connected to 0V.
6. Feedback (pin 4) removed from output and connected to 12V to force the output transistor OFF.
7. Junction-to-ambient thermal resistance with approximately 1 square inches of PC board copper surrounding the leads.
Test Circuit
CIN
22µF
FB
VIN
LM2574
(adjustable)
OUT
PWR SIG ON/
GND GND OFF
330µH
11DQ06
CO U T
220µF
3.09k
1k
4
0.01
Micrel, Inc.
Max Units
100
nA
500
nA
58
kHz
63
kHz
1.2
V
1.4
V
%
1.6
A
1.8
2
mA
30
10
mA
200
µA
°C/W
V
V
1.0
V
0.8
V
30
µA
10
µA
Figure 2. Adjustable Regulator Test Circuit
CIN
22µF
FB
VIN
LM2574–
3.3, 5, 12
OUT
P W R SIG ON/
GND GND OFF
330µH
11DQ06
CO U T
220µF
Figure 3. Fixed Regulator Test Circuit
M9999-072805
4
July 2005
Share Link: 