U3848 Datasheet, PDF (4/12 Pages) Unisonic Technologies – HIGH PERFORMANCE CURRENT MODE PWM CONTROLLERS

UC3848
LINEAR INTEGRATED CIRCUIT

„ ABSOLUTE MAXIMUM RATINGS (TaĢ25°C, V_CC=15V, unless otherwise specified)
PARAMETER
SYMBOL
RATINGS
UNIT
Supply Voltage
V_CC
26
V
Input Voltage to FB Pin
V_FB
-0.3 ~ 6.2
V
Input Voltage to CS Pin
V_CS
-0.3 ~ 2.8
V
Junction Temperature
T_J
+150
°C
Operating Temperature
T_OPR
-40 ~ +125
°C
Storage Temperature
T_STG
-50 ~ +150
°C
Note Absolute maximum ratings are those values beyond which the device could be permanently damaged.




Absolute maximum ratings are stress ratings only and functional device operation is not implied.
„ RECOMMENDED OPERATING CONDITIONS
PARAMETER
SYMBOL
Supply Voltage
V_CC
RATINGS
8.2 ~ 21
UNIT
V
„ ELECTRICAL CHARACTERISTICS (TaĢ25°C, V_CC=15V, unless otherwise specified)
PARAMETER
SYMBOL TEST CONDITIONS
MIN TYP MAX
SUPPLY SECTION
Start Up Current
I_STR V_CC=12.5V
27
45
Supply Current with switch
OFF
ON
I_OFF V_SS = 0, I_FB = 0
I_ON V_SS = 5V, I_FB = 0
3.7 5.5
4.0 6.0
UNDER-VOLTAGE LOCKOUT SECTION
Start Threshold Voltage
V_THD(ON)
11.8 12.6 13.4
Min. Operating Voltage
V_CC(MIN)
7.6 8.1 8.6
Hysteresis
V_CC(HY)
4.5
INTERNAL VOLTAGE REFERENCE
Reference Voltage
V_REF measured at pin V_REF
6.1 6.3 6.6
CONTROL SECTION
Switch Frequency
Normal
Power-Saving
F_(SW)
V_FB = 4V
V_FB = 1V
61
68
75
17
20
24
Duty Cycle
MAX
MIN
D_MAX
D_MIN
V_FB < 0.5V
65
70
75
0
V_FB Operating Level
MIN
MAX
V_MIN
V_MAX
0.5
4.4
Feedback Resistor
R_FB
2.6 3.8 5.0
C_SS=0.05uF
6
Soft-Start Time
T_{SS CSS=0.1uF}
12
C_SS=1uF
120
PROTECTION SECTION
OVP threshold
V_(OVP) V_SS < 3.5V, V_FB > 5V
15.2 16 16.8
OLP threshold
V_FB(OLP) V_SS > 5.4V
4.4 4.6 4.9
OTP threshold
T_(THR)
120 135 150
OVP Disable threshold
V_SS(DEACT) V_FB > 5V, V_CC > 17V
3.7 3.9 4.2
OLP Enable threshold
V_SS(ACT) V_FB > 5V
4.9 5.1 5.4
Spike Blanking time
T_SB
7.2
CURRENT LIMITING SECTION
LEB
t_LEB
220
DRIVER OUTPUT SECTION
Output Voltage Low State
V_OL I_SOURCE = 200 mA
2.5
Output Voltage High State
V_OH I_SINK = 200 mA
12.2
Output Voltage Rise Time
t_R C_L = 1.0 nF
300 400
Output Voltage Fall Time
t_F C_L = 1.0 nF
50
90
UNIT
µA
mA
mA
V
V
V
V
kHz
kHz
%
%
V
V
kΩ
ms
ms
ms
V
V
°C
V
V
µs
ns
V
V
ns
ns
UNISONIC TECHNOLOGIES CO., LTD
www.unisonic.com.tw
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QW-R103-033,C