UC2844NG View Datasheet(PDF) - ON Semiconductor
Part Name
Description
View to exact match
UC2844NG Datasheet PDF : 16 Pages
| |||
UC3844, UC3845, UC2844, UC2845
ELECTRICAL CHARACTERISTICS (VCC = 15 V, (Note 4), RT = 10 k, CT = 3.3 nF, TA = Tlow to Thigh (Note 5), unless otherwise noted.)
UC284X
UC384X
Characteristics
Symbol
Min Typ Max Min Typ Max Unit
ERROR AMPLIFIER SECTION (continued)
Unity Gain Bandwidth (TJ = 25°C)
Power Supply Rejection Ratio (VCC = 12 V to 25 V)
Output Current
Sink (VO = 1.1 V, VFB = 2.7 V)
Source (VO = 5.0 V, VFB = 2.3 V)
Output Voltage Swing
High State (RL = 15 k to ground, VFB = 2.3 V)
Low State (RL = 15 k to Vref, VFB = 2.7 V)
CURRENT SENSE SECTION
Current Sense Input Voltage Gain (Notes 6 & 7)
Maximum Current Sense Input Threshold (Note 6)
Power Supply Rejection Ratio
VCC = 12 V to 25 V (Note 6)
Input Bias Current
Propagation Delay (Current Sense Input to Output)
OUTPUT SECTION
Output Voltage
Low State (ISink = 20 mA)
(ISink = 200 mA)
High State (ISink = 20 mA)
(ISink = 200 mA)
Output Voltage with UVLO Activated
VCC = 6.0 V, ISink = 1.0 mA
Output Voltage Rise Time (CL = 1.0 nF, TJ = 25°C)
Output Voltage Fall Time (CL = 1.0 nF, TJ = 25°C)
UNDERVOLTAGE LOCKOUT SECTION
Startup Threshold
UCX844
UCX845
BW
PSRR
ISink
ISource
VOH
VOL
0.7 1.0
−
0.7 1.0
−
MHz
60
70
−
60
70
−
dB
mA
2.0
12
−
2.0
12
−
−0.5 −1.0
−
−0.5 −1.0
−
V
5.0 6.2
−
5.0 6.2
−
−
0.8 1.1
−
0.8 1.1
AV
Vth
PSRR
2.85 3.0 3.15 2.85 3.0 3.15 V/V
0.9 1.0 1.1 0.9 1.0 1.1
V
−
70
−
dB
−
70
−
IIB
tPLH(IN/OUT)
−
−2.0 −10
−
150 300
−
−2.0 −10
mA
−
150 300
ns
VOL
VOH
VOL(UVLO)
tr
tf
V
−
0.1 0.4
−
0.1 0.4
−
1.6 2.2
−
1.6 2.2
12 13.5
−
13 13.5
−
12 13.4
−
12 13.4
−
V
−
0.1 1.1
−
0.1 1.1
−
50 150
−
50
150
ns
−
50 150
−
50
150
ns
Vth
V
15
16
17 14.5 16 17.5
7.8 8.4 9.0 7.8 8.4 9.0
Minimum Operating Voltage After Turn−On
UCX844
UCX845
VCC(min)
V
9.0
10
11
8.5
10
11.5
7.0 7.6 8.2 7.0 7.6 8.2
PWM SECTION
Duty Cycle
Maximum
Minimum
DCmax
DCmin
%
46
48
50
47
48
50
−
−
0
−
−
0
TOTAL DEVICE
Power Supply Current (Note 4)
Startup:
(VCC = 6.5 V for UCX845A,
(VCC 14 V for UCX844) Operating
ICC
mA
−
0.5 1.0
−
0.5 1.0
−
12
17
−
12
17
Power Supply Zener Voltage (ICC = 25 mA)
VZ
30
36
−
30
36
−
V
4. Adjust VCC above the Startup threshold before setting to 15 V.
5. Low duty cycle pulse techniques are used during test to maintain junction temperature as close to ambient as possible.
Tlow = 0°C for UC3844, UC3845
−25°C for UC2844, UC2845
Thigh = +70°C for UC3844, UC3845
+85°C for UC2844, UC2845
6. This parameter is measured at the latch trip point with VFB = 0 V.
7. Comparator gain is defined as: AV DV Output Compensation
DV Current Sense Input
http://onsemi.com
3
|
|
Share Link: 