UC1842A/3A/4A/5A
UC2842A/3A/4A/5A
UC3842A/3A/4A/5A
ELECTRICAL CHARACTERISTICS (cont.)
Unless otherwise stated, these specifications apply for -55°C
≤
T
A
≤
125°C for
the UC184xA; -40°C
≤
T
A
≤
85°C for the UC284xA; 0
≤
T
A
≤
70°C for the UC384xA; V
CC
= 15V (Note 5); R
T
= 10k; C
T
= 3.3nF; T
A
= T
J
;
Pin numbers refer to DIL-8.
PARAMETER
Error Amp Section
Input Voltage
Input Bias Current
A
VOL
Unity Gain Bandwidth
PSRR
Output Sink Current
Output Source Current
V
OUT
High
V
OUT
Low
Current Sense Section
Gain
Maximum Input Signal
PSRR
Input Bias Current
Delay to Output
Output Section
Output Low Level
Output High Level
Rise Time
Fall Time
UVLO Saturation
Under-Voltage Lockout Section
Start Threshold
Min. Operation Voltage After
Turn On
PWM Section
Maximum Duty Cycle
Minimum Duty Cycle
Total Standby Current
Start-Up Current
Operating Supply Current
V
CC
Zener Voltage
TEST CONDITIONS
UC184xA\UC284xA
MIN. TYP. MAX.
2.45
65
0.7
60
2
-0.5
5
2.50
-0.3
90
1
70
6
-0.8
6
0.7
3
1
70
-2
150
0.1
15
13.5
13.5
50
50
0.7
16
8.4
10
7.6
96
48
2.55
-1
UC384xA
UNITS
MIN. TYP. MAX.
2.42
65
0.7
60
2
-0.5
5
1.1
3.15
1.1
-10
300
0.4
2.2
13
12
150
150
1.2
17
9.0
11
8.2
100
50
0
0.5
17
30
14.5
7.8
8.5
7.0
94
47
2.85
0.9
2.50
-0.3
90
1
70
6
-0.8
6
0.7
3
1
70
-2
150
0.1
15
13.5
13.5
50
50
0.7
16
8.4
10
7.6
96
48
2.58
-2
V
µA
dB
MHz
dB
mA
mA
V
V
V/V
V
dB
µA
ns
V
V
V
V
ns
ns
V
V
V
V
V
%
%
%
mA
mA
V
V
PIN 1
= 2.5V
2
≤
V
O
≤
4V
T
J
= 25°C (Note 2)
12
≤
V
CC
≤
25V
V
PIN 2
= 2.7V, V
PIN 1
= 1.1V
V
PIN 2
= 2.3V, V
PIN 1
= 5V
V
PIN 2
= 2.3V, R
L
= 15k to ground
V
PIN 2
= 2.7V, R
L
= 15k to Pin 8
(Note 3, Note 4)
V
PIN 1
= 5V (Note 3)
12
≤
V
CC
≤
25V (Note 3)
V
PIN 3
= 0 to 2V (Note 2)
I
SINK
= 20mA
I
SINK
= 200mA
I
SOURCE
= 20mA
I
SOURCE
= 200mA
T
J
= 25°C, C
L
= 1nF (Note 2)
T
J
= 25°C, C
L
= 1nF (Note 2)
V
CC
= 5V, I
SINK
= 10mA
x842A/4A
x843A/5A
x842A/4A
x843A/5A
x842A/3A
x844A/5A
1.1
3.15
1.1
-10
300
0.4
2.2
2.85
0.9
13
12
150
150
1.2
17.5
9.0
11.5
8.2
100
50
0
0.5
17
15
7.8
9
7.0
94
47
V
PIN 2
= V
PIN 3
= 0V
I
CC
= 25mA
30
0.3
11
34
0.3
11
34
Note 2: These parameters, although guaranteed, are not 100%
tested in production.
Note 3: Parameter measured at trip point of latch with V
PIN2
= 0.
∆
V
PIN 1
Note 4: Gain defined as: A
=
; 0
≤
V
PIN 3
≤
0.8V.
∆
V
PIN 3
Note 5: Adjust V
CC
above the start threshold before setting at
15V.
Note 6: Output frequency equals oscillator frequency for the
UC1842A and UC1843A. Output frequency is one half
oscillator frequency for the UC1844A and UC1845A.
Note 7: "Temperature stability, sometimes referred to as average
temperature coefficient, is described by the equation:
V
REF
(
max
)
−
V
REF
(
min
)
.
T
J
(
max
) −
T
J
(
min
)
V
REF
(max) and V
REF
(min) are the maximum & mini-
mum reference voltage measured over the appropriate
temperature range. Note that the extremes in voltage
do not necessarily occur at the extremes in tempera-
ture."
Note 8: This parameter is measured with R
T
= 10k
Ω
to V
REF
.
This contributes approximately 300
µ
A of current to the
measurement. The total current flowing into the R
T
/C
T
pin will be approximately 300
µ
A higher than the meas-
ured value.
Temp Stability
=
3
TI [ TEXAS INSTRUMENTS ]
