UC3844, 45 UC2844, 45
MAXIMUM RATINGS
Rating
Symbol
(I + I )
Value
Unit
mA
A
Total Power Supply and Zener Current
Output Current, Source or Sink (Note 1)
Output Energy (Capacitive Load per Cycle)
Current Sense and Voltage Feedback Inputs
Error Amp Output Sink Current
30
CC
Z
I
O
1.0
5.0
W
µJ
V
in
– 0.3 to + 5.5
10
V
I
O
mA
Power Dissipation and Thermal Characteristics
D Suffix, Plastic Package, Case 751A
Maximum Power Dissipation @ T = 25°C
Thermal Resistance Junction–to–Air
N Suffix, Plastic Package, Case 626
P
862
145
mW
°C/W
A
D
R
θJA
Maximum Power Dissipation @ T = 25°C
Thermal Resistance Junction–to–Air
P
1.25
100
W
°C/W
A
D
R
θJA
Operating Junction Temperature
T
+ 150
°C
°C
J
Operating Ambient Temperature
UC3844, UC3845
T
A
0 to + 70
UC2844, UC2845
– 25 to + 85
Storage Temperature Range
T
stg
– 65 to + 150
°C
ELECTRICAL CHARACTERISTICS (V
unless otherwise noted.)
= 15 V, [Note 2], R = 10 k, C = 3.3 nF, T = T
to T [Note 3],
high
CC
T
T
A
low
UC284X
Typ
UC384X
Typ
Characteristics
Symbol
Min
Max
Min
Max
Unit
REFERENCE SECTION
Reference Output Voltage (I = 1.0 mA, T = 25°C)
V
ref
4.95
–
5.0
2.0
3.0
0.2
–
5.05
20
4.9
–
5.0
2.0
3.0
0.2
–
5.1
20
V
mV
mV
mV/°C
V
O
J
Line Regulation (V
CC
= 12 V to 25 V)
Reg
line
load
S
Load Regulation (I = 1.0 mA to 20 mA)
O
Reg
T
–
25
–
25
Temperature Stability
–
–
–
–
Total Output Variation over Line, Load, Temperature
Output Noise Voltage (f = 10 Hz to kHz, T = 25°C)
V
ref
4.9
–
5.1
–
4.82
–
5.18
–
V
n
50
50
µV
J
Long Term Stability (T = 125°C for 1000 Hours)
S
–
5.0
– 85
–
–
5.0
– 85
–
mV
mA
A
Output Short Circuit Current
I
– 30
– 180
– 30
– 180
SC
OSCILLATOR SECTION
Frequency
f
kHz
osc
T = 25°C
47
46
52
–
57
60
47
46
52
–
57
60
J
A
T
= T
to T
high
low
Frequency Change with Voltage (V
= 12 V to 25 V)
∆f
∆
osc/ V
–
–
0.2
5.0
1.0
–
–
–
0.2
5.0
1.0
–
%
%
CC
Frequency Change with Temperature
= T to T
∆f
∆
osc/ T
T
A
low
Oscillator Voltage Swing (Peak–to–Peak)
Discharge Current (V = 2.0 V, T = 25°C)
high
V
osc
–
–
1.6
–
–
–
–
1.6
–
–
V
I
dischg
10.8
10.8
mA
osc
J
NOTES: 1. Maximum Package power dissipation limits must be observed.
2. Adjust V above the Startup threshold before setting to 15 V.
CC
3. Low duty cycle pulse techniques are used during test to maintain junction temperature as close to ambient as possible
T
T
= –20°C for UC3844, UC3845
= –25°C for UC2844, UC2845
T
T
= +70°C for UC3844, UC3845
= +85°C for UC2844, UC2845
low
low
high
high
2
MOTOROLA ANALOG IC DEVICE DATA