UC3844, 45 UC2844, 45
MAXIMUM RATINGS
Rating
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
Power Dissipation and Thermal Characteristics
D Suffix, Plastic Package, Case 751A
Maximum Power Dissipation @ TA = 25°C
Thermal Resistance Junction–to–Air
N Suffix, Plastic Package, Case 626
Maximum Power Dissipation @ TA = 25°C
Thermal Resistance Junction–to–Air
Operating Junction Temperature
Operating Ambient Temperature
UC3844, UC3845
UC2844, UC2845
Storage Temperature Range
Symbol
(ICC + IZ)
IO
W
Vin
IO
Value
30
1.0
5.0
– 0.3 to + 5.5
10
Unit
mA
A
µJ
V
mA
PD
R
θJA
PD
R
θJA
TJ
TA
862
145
1.25
100
+ 150
0 to + 70
– 25 to + 85
mW
°C/W
W
°C/W
°C
°C
Tstg
– 65 to + 150
°C
ELECTRICAL CHARACTERISTICS
(VCC = 15 V, [Note 2], RT = 10 k, CT = 3.3 nF, TA = Tlow to Thigh [Note 3],
unless otherwise noted.)
UC284X
Characteristics
REFERENCE SECTION
Reference Output Voltage (IO = 1.0 mA, TJ = 25°C)
Line Regulation (VCC = 12 V to 25 V)
Load Regulation (IO = 1.0 mA to 20 mA)
Temperature Stability
Total Output Variation over Line, Load, Temperature
Output Noise Voltage (f = 10 Hz to kHz, TJ = 25°C)
Long Term Stability (TA = 125°C for 1000 Hours)
Output Short Circuit Current
OSCILLATOR SECTION
Frequency
TJ = 25°C
TA = Tlow to Thigh
Frequency Change with Voltage (VCC = 12 V to 25 V)
Frequency Change with Temperature
TA = Tlow to Thigh
Oscillator Voltage Swing (Peak–to–Peak)
Discharge Current (Vosc = 2.0 V, TJ = 25°C)
fosc
47
46
∆f
osc/
∆
V
∆f
osc/
∆
T
Vosc
Idischg
–
–
–
–
52
–
0.2
5.0
1.6
10.8
57
60
1.0
–
–
–
47
46
–
–
–
–
52
–
0.2
5.0
1.6
10.8
57
60
1.0
–
–
–
%
%
V
mA
kHz
Vref
Regline
Regload
TS
Vref
Vn
S
ISC
4.95
–
–
–
4.9
–
–
– 30
5.0
2.0
3.0
0.2
–
50
5.0
– 85
5.05
20
25
–
5.1
–
–
– 180
4.9
–
–
–
4.82
–
–
– 30
5.0
2.0
3.0
0.2
–
50
5.0
– 85
5.1
20
25
–
5.18
–
–
– 180
V
mV
mV
mV/°C
V
µV
mV
mA
Symbol
Min
Typ
Max
Min
UC384X
Typ
Max
Unit
NOTES:
1. Maximum Package power dissipation limits must be observed.
2. Adjust VCC above the Startup threshold before setting to 15 V.
3. Low duty cycle pulse techniques are used during test to maintain junction temperature as close to ambient as possible
Tlow =
–20°C
for UC3844, UC3845
Thigh = +70°C for UC3844, UC3845
Tlow =
–25°C for UC2844, UC2845
Thigh =
+85°C for UC2844, UC2845
2
MOTOROLA ANALOG IC DEVICE DATA
ONSEMI [ ON SEMICONDUCTOR ]
