OMO ElectronicOMO Electronic
Expand menu
Hello, Sign inMy Account
0 Cart

E-UC3845BD1013TR

P1-P3P4-P6P7-P9P10-P12P13-P15
Notes :
1. Max package power dissipation limits must be respected; low duty cycle pulse techniques are used during test maintain T
j
as
close to T
amb
as possible.
2. These parameters, although guaranteed, are not 100% tested in production.
3. Parameter measured at trip point of latch with V
PIN2
= 0.
4. Gain defined as :
∆
V
PIN1
A = ; 0
≤
V
PIN3
≤
0.8 V
∆
V
PIN3
5. Adjust V
i
above the start threshold before setting at 15 V.
ELECTRICAL CHARACTERISTICS (continued)
Symbol Parameter Test Conditions
UC284XB UC384XB
Unit
Min. Typ. Max. Min. Typ. Max.
OUTPUT SECTION
V
OL
Output Low Level I
SINK
= 20mA 0.1 0.4 0.1 0.4 V
I
SINK
= 200mA 1.6 2.2 1.6 2.2 V
V
OH
Output High Level I
SOURCE
= 20mA 13 13.5 13 13.5 V
I
SOURCE
= 200mA 12 13.5 12 13.5 V
V
OLS
UVLO Saturation VCC = 6V; I
SINK
= 1mA 0.1 1.1 0.1 1.1 V
t
r
Rise Time
T
j
= 25
°
C C
L
= 1nF (2)
50 150 50 150 ns
t
f
Fall Time
T
j
= 25
°
C C
L
= 1nF (2)
50 150 50 150 ns
UNDER-VOLTAGE LOCKOUT SECTION
Start Threshold X842B/4B 15 16 17 14.5 16 17.5 V
X843B/5B 7.8 8.4 9.0 7.8 8.4 9.0 V
Min Operating Voltage
After Turn-on
X842B/4B 9 10 11 8.5 10 11.5 V
X843B/5B 7.0 7.6 8.2 7.0 7.6 8.2 V
PWM SECTION
Maximum Duty Cycle X842B/3B 94 96 100 94 96 100 %
X844B/5B 474850474850 %
Minimum Duty Cycle 0 0 %
TOTAL STANDBY CURRENT
I
st
Start-up Current V
i
= 6.5V for UCX843B/45B 0.3 0.5 0.3 0.5 mA
V
i
= 14V for UCX842B/44B 0.3 0.5 0.3 0.5 mA
I
i
Operating Supply Current V
PIN2
= V
PIN3
= 0V 12 17 12 17 mA
V
iz
Zener Voltage I
i
= 25mA 30 36 30 36 V
UC2842B/3B/4B/5B - UC3842B/3B/4B/5B
4/15
Figure 1: Open Loop Test Circuit.
R
T
A2N2222
4.7KΩ
1KΩ
ERROR AMP.
ADJUST
4.7KΩ
5KΩ
I
SENSE
ADJUST
100KΩ
COMP
V
FB
I
SENSE
R
T
/C
T
1
2
3
4
C
T
7
6
5
8
V
REF
V
i
OUTPUT
GROUND
0.1µF
0.1µF
V
REF
V
i
OUTPUT
GROUND
1W
1KΩ
D95IN343
High peak currents associated with capacitive loads
necessitate careful grounding techniques. Timing
and bypass capacitors should be connected close
to pin 5 in a single point ground. The transistor and
5 KΩ potentiometer are used to sample the oscillator
waveform and apply an adjustable ramp to pin 3.
10K 20K 30K 50K 100K 200K 300K 500K f
OSC
(KHz)
1
2
5
10
20
50
D95IN333
C
T
=10nF
C
T
=5nF
C
T
=2nF
C
T
=1nF
C
T
=500pF
C
T
=200pF
C
T
=100pF
V
i
=15V
T
A
=25˚C
RT
(KΩ)
0.8
Figure 2: Timing Resistor vs. Oscillator Fre-
quency
10K 20K 30K 50K 100K 200K 300K 500K fOSC(KHz)
1
2
3
5
10
20
30
50
%
C
T
=10nF
C
T
=5nF
C
T
=2nF
C
T
=1nF
C
T
=500pF
C
T
=200pF
C
T
=100pF
D95IN334
V
i
=15V
T
A
=25˚C
Figure 3: Output Dead-Time vs. Oscillator Fre-
quency
UC2842B
UC2842B/3B/4B/5B - UC3842B/3B/4B/5B
5/15
-55 -25 0 25 50 75 100 T
A
(˚C)
7.0
7.5
8.0
8.5
I
dischg
(mA)
D95IN335
V
i
=15V
V
OSC
=2V
Figure 4: Oscillator Discharge Current vs. Tem-
perature.
1235
40
50
60
70
80
90
D
max
(%)
0.8 R
T
(KΩ)
D95IN336
V
i
=15V
C
T
=3.3nF
T
A
=25˚C
I
dischg
=7.5mA
I
dischg
=8.8mA
Figure 5: Maximum Output Duty Cycle vs. Tim-
ing Resistor.
10 100 1K 10K 100K 1M f(Hz)
-20
0
20
40
60
80
(dB)
180
150
120
90
60
30
φ
D95IN337
V
i
=15V
V
O
=2V to 4V
R
L
=100K
T
A
=25˚C
Gain
Phase
Figure 6: Error Amp Open-Loop Gain and
Phase vs. Frequency.
0246V
O
(V)
0.0
0.2
0.4
0.6
0.8
1.0
V
th
(V)
D95IN338
V
i
=15V
T
A
=-40˚C
T
A
=125˚C
T
A
=25˚C
Figure 7: Current Sense Input Threshold vs. Er-
ror Amp Output Voltage.
0 20406080100I
ref
(mA)
D95IN339
0
10
20
30
40
50
60
V
i
=15V
T
A
=-40˚C
T
A
=125˚C
T
A
=25˚C
Figure 8: Reference Voltage Change vs.
Source Current.
-55 -25 0 25 50 75 100 T
A
(˚C)
D95IN340
50
60
70
80
90
100
I
SC
(mA)
V
i
=15V
R
L
≤0.1Ω
Figure 9: Reference Short Circuit Current vs.
Temperature.
UC2842B/3B/4B/5B - UC3842B/3B/4B/5B
6/15
P1-P3P4-P6P7-P9P10-P12P13-P15

E-UC3845BD1013TR

Mfr. #:
Buy E-UC3845BD1013TR
Manufacturer:
STMicroelectronics
Description:
Switching Controllers 0.5mA Current Mode
Lifecycle:
New from this manufacturer.
Delivery:
DHL FedEx Ups TNT EMS
Payment:
T/T Paypal Visa MoneyGram Western Union

Products related to this Datasheet