1.0A Step-Down Switching Regulator
TC2575
ELECTRICAL CHARACTERISTICS: (Unless otherwise specified, VIN = 12V for the 3.3V, 5.0V, and Adjustable
version,VIN = 25V for the 12V version. ILOAD = 200mA. For typical values TJ = 25°C, for min/max values TJ is the operat-
ing junction temperature range that applies (Note 2), unless otherwise noted.
Symbol
Parameter
Test Conditions
Min
Typ
Max
Units
TC2575-ALL OUTPUT VOLTAGE VERSIONS
Ib
Feedback Bias Current
VOUT = 5.0V (Adjustable Version Only)
TJ = 25°C
nA
—
—
25
—
100
200
TJ = –40°C to +125°C
fOSC
Oscillator Frequency (Note 3)
Saturation Voltage
TJ = 25°C
TJ = 0 to +125°C
TJ = –40 to +125°C
—
47
42
52
—
—
—
58
63
kHz
V
VSAT
IOUT = 1.0A, (Note 4)
TJ = 25°C
TJ = –40 to +125°C
—
—
1.0
—
1.2
1.3
DC
ICL
Max Duty Cycle (“on”) [Note 5]
94
98
—
%
A
Current Limit Peak Current
(Notes 3 and 4)
TJ = 25°C
TJ = –40 to +125°C
1.7
1.4
2.3
—
3.0
3.2
IL
Output Leakage Current
(Notes 6 and 7), TJ = 25°C
mA
mA
µA
V
Output = 0 V
Output = – 1.0 V
—
—
0.8
6.0
2.0
20
IQ
Quiescent Current (Note 6)
TJ = 25°C
TJ = –40 to +125°C
—
—
5.0
—
9.0
11
ISTBY
Standby Quiescent Current,
ON/OFF Pin = 5.0 V (“off”)
TJ = 25°C
TJ = –40 to +125°C
—
—
80
—
200
400
VIH
ON/OFF Pin Logic Input Level
(Test Figure 2)
VOUT = 0V
TJ = 25°C
TJ = –40 to +125°C
2.2
2.4
1.4
—
—
—
VIL
IIH
IIL
Nominal Output Voltage
VOUT = Nominal Output Voltage
TJ = 25°C
TJ = –40 to +125°C
V
—
—
1.2
—
1.0
0.8
ON/OFF Pin Input Current
(Test Figure 2)
µA
µA
ON/OFF Pin = 5.0V (“off”),
TJ = 25°C
—
—
15
0
30
ON/OFF Pin Input Current
ON/OFF Pin = 0V (“on”),
5.0
TJ = 25°C
NOTES: 3. The oscillator frequency reduces to approximately 18kHz in the event of an output short or an overload which causes the regulated
output voltage to drop approximately 40% from the nominal output voltage. This self protection feature lowers the average power
dissipation of the IC by lowering the minimum duty cycle from 5% down to approximately 2%.
4. Output (Pin 2) sourcing current. No diode, inductor or capacitor connected to the output pin.
5. Feedback (Pin 4) removed from output and connected to 0V.
6. Feedback (Pin 4) removed from output and connected to +12V for the Adjustable, 3.3V, and 5.0V versions, and 25V for the 12V,
to force the output transistor "OFF".
7. VIN = 40 V.
3
TC2575-1 3/13/00