TL284x, TL384x
CURRENT-MODE PWM CONTROLLERS
SLVS038E – JANUARY 1989 – REVISED DECEMBER 1999
electrical characteristics over recommended operating free-air temperature range, V = 15 V (see
CC
Note 4), R = 10 kΩ, C = 3.3 nF (unless otherwise specified) (continued)
T
T
current-sense section
TL284x
TL384x
PARAMETER
TEST CONDITIONS
UNIT
†
†
MIN TYP
2.85
MAX
3.13
1.1
MIN TYP
2.85
MAX
3.15
1.1
Voltage amplification
See Notes 6 and 7
COMP at 5 V,
= 12 V to 25 V, See Note 6
3
1
3
1
V/V
V
Current-sense comparator threshold
Supply-voltage rejection ratio
Input bias current
See Note 6
0.9
0.9
V
CC
70
–2
70
–2
dB
µA
ns
–10
300
–10
300
Delay time to output
150
150
†
All typical values are at T = 25°C.
A
NOTES: 4. Adjust V
above the start threshold before setting it to 15 V.
CC
6. These parameters are measured at the trip point of the latch, with VFB at 0 V.
7. Voltage amplification is measured between ISENSE and COMP, with the input changing from 0 V to 0.8 V.
output section
TL284x
TL384x
PARAMETER
High-level output voltage
Low-level output voltage
TEST CONDITIONS
= –20 mA
UNIT
V
†
†
MIN TYP
MAX
MIN TYP
MAX
I
I
I
I
13
12
13.5
13.5
0.1
1.5
50
13
12
13.5
13.5
0.1
1.5
50
OH
OH
OL
OL
= –200 mA
= 20 mA
= 200 mA
= 1 nF,
0.4
2.2
0.4
2.2
V
Rise time
Fall time
C
C
T
A
= 25°C
= 25°C
150
150
150
150
ns
ns
L
L
= 1 nF,
T
A
50
50
†
All typical values are at T = 25°C.
A
NOTE 4: Adjust V
above the start threshold before setting it to 15 V.
CC
undervoltage-lockout section
TL284x
TL384x
PARAMETER
UNIT
V
†
†
MIN TYP
MAX
17
MIN TYP
MAX
17.5
9
TLx842, TLx844
TLx843, TLx845
TLx842, TLx844
TLx843, TLx845
15
7.8
9
16
8.4
10
14.5
7.8
8.5
7
16
8.4
10
Start threshold voltage
9
11
11.5
8.2
Minimum operating voltage after startup
V
7
7.6
8.2
7.6
†
All typical values are at T = 25°C.
A
NOTE 4: Adjust V
above the start threshold before setting it to 15 V.
CC
pulse-width-modulator section
TL284x
TL384x
PARAMETER
UNIT
†
†
MIN TYP
MAX
MIN TYP
MAX
TLx842, TLx843
TLx844, TLx845
95%
46%
97% 100%
95%
46%
97% 100%
Maximum duty cycle
Minimum duty cycle
48%
50%
0
48%
50%
0
†
All typical values are at T = 25°C.
A
NOTE 4: Adjust V
above the start threshold before setting it to 15 V.
CC
5
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