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UC2843AのメーカーはON Semiconductorです、この部品の機能は「High Performance Current Mode Controllers」です。 |
部品番号 | UC2843A |
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部品説明 | High Performance Current Mode Controllers | ||
メーカ | ON Semiconductor | ||
ロゴ | |||
このページの下部にプレビューとUC2843Aダウンロード(pdfファイル)リンクがあります。 Total 18 pages
UC3842A, UC3843A,
UC2842A, UC2843A
High Performance
Current Mode Controllers
The UC3842A, UC3843A series of high performance fixed
frequency current mode controllers are specifically designed for
off−line and DC−to−DC converter applications offering the designer a
cost effective solution with minimal external components. These
integrated circuits feature a trimmed oscillator for precise duty cycle
control, a temperature compensated reference, high gain error
amplifier, current sensing comparator, and a high current totem pole
output ideally suited for driving a power MOSFET.
Also included are protective features consisting of input and
reference undervoltage lockouts each with hysteresis, cycle−by−cycle
current limiting, programmable output deadtime, and a latch for single
pulse metering.
These devices are available in an 8−pin dual−in−line plastic package
as well as the 14−pin plastic surface mount (SOIC−14). The SOIC−14
package has separate power and ground pins for the totem pole output
stage.
The UCX842A has UYLO thresholds of 16 V (on) and 10 V (off),
ideally suited for off−line converters. The UCX843A is tailored for
lower voltage applications having UVLO thresholds of 8.5 V (on) and
7.6 V (off).
Features
• Trimmed Oscillator Discharge Current for Precise Duty Cycle
Control
• Current Mode Operation to 500 kHz
• Automatic Feed Forward Compensation
• Latching PWM for Cycle−By−Cycle Current Limiting
• Internally Trimmed Reference with Undervoltage Lockout
• High Current Totem Pole Output
• Undervoltage Lockout with Hysteresis
• Low Startup and Operating Current
• Direct Interface with ON Semiconductor SENSEFET™ Products
• Pb−Free Packages are Available
http://onsemi.com
8
1
14
1
PDIP−8
N SUFFIX
CASE 626
SOIC−14
D SUFFIX
CASE 751A
8
1
SOIC−8
D1 SUFFIX
CASE 751
PIN CONNECTIONS
Compensation 1
Voltage Feedback 2
Current Sense 3
RT/CT 4
8 Vref
7 VCC
6 Output
5 GND
(Top View)
Compensation 1
NC 2
Voltage Feedback 3
NC 4
Current Sense 5
NC 6
RT/CT 7
14 Vref
13 NC
12 VCC
11 VC
10 Output
9 GND
8 Power Ground
(Top View)
© Semiconductor Components Industries, LLC, 2005
November, 2005 − Rev. 8
ORDERING INFORMATION
See detailed ordering and shipping information in the package
dimensions section on page 15 of this data sheet.
DEVICE MARKING INFORMATION
See general marking information in the device marking
section on page 16 of this data sheet.
1 Publication Order Number:
UC3842A/D
1 Page UC3842A, UC3843A, UC2842A, UC2843A
ELECTRICAL CHARACTERISTICS (VCC = 15 V, [Note 2], RT = 10 k, CT = 3.3 nF, TA = Tlow to Thigh [Note 3],
unless otherwise noted.)
UC284XA
UC384XA
Characteristics
Symbol Min Typ Max Min Typ Max
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 10 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
Vref
Regline
Regload
TS
Vref
Vn
S
ISC
fosc
Dfosc/DV
Dfosc/DT
4.95
−
−
−
4.9
−
−
− 30
47
46
−
−
5.0 5.05 4.9
2.0 20
−
3.0 25
−
0.2 −
−
− 5.1 4.82
50 −
−
5.0 −
−
− 85 − 180 − 30
52 57
− 60
0.2 1.0
5.0 −
47
46
−
−
5.0 5.1
2.0 20
3.0 25
0.2 −
− 5.18
50 −
5.0 −
− 85 − 180
52 57
− 60
0.2 1.0
5.0 −
Oscillator Voltage Swing (Peak−to−Peak)
Discharge Current (Vosc = 2.0 V)
TJ = 25°C
TA = Tlow to Thigh
Vosc − 1.6 − − 1.6 −
Idischg
7.5 8.4 9.3 7.5 8.4 9.3
7.2 − 9.5 7.2 − 9.5
ERROR AMPLIFIER SECTION
Voltage Feedback Input (VO = 2.5 V)
VFB 2.45 2.5 2.55 2.42 2.5 2.58
Input Bias Current (VFB = 2.7 V)
IIB − −0.1 −1.0 − −0.1 −2.0
Open Loop Voltage Gain (VO = 2.0 V to 4.0 V)
AVOL 65 90 − 65 90 −
Unity Gain Bandwidth (TJ = 25°C)
BW 0.7 1.0 − 0.7 1.0 −
Power Supply Rejection Ratio (VCC = 12 V to 25 V) PSRR 60 70 − 60 70 −
Output Current
Sink (VO = 1.1 V, VFB = 2.7 V)
Source (VO = 5.0 V, VFB = 2.3 V)
ISink 2.0 12 − 2.0 12 −
ISource
−0.5 −1.0
−
−0.5 −1.0
−
Output Voltage Swing
High State (RL = 15 k to ground, VFB = 2.3 V)
Low State (RL = 15 k to Vref, VFB = 2.7 V)
VOH 5.0 6.2 − 5.0 6.2 −
VOL − 0.8 1.1 − 0.8 1.1
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 = 0°C for UC3842A, UC3843A
−25°C for UC2842A, UC2843A
Thigh = +70°C for UC3842A, UC3843A
+85°C for UC2842A, UC2843A
Unit
V
mV
mV
mV/°C
V
mV
mV
mA
kHz
%
%
V
mA
V
mA
dB
MHz
dB
mA
V
http://onsemi.com
3
3Pages UC3842A, UC3843A, UC2842A, UC2843A
100 0
VCC = 15 V
80
Gain
VO = 2.0 V to 4.0 V
RL = 100 K
30
TA = 25°C
60 60
40 90
Phase
20 120
0 150
− 20
10
100 1.0 k 10 k 100 k 1.0 M
f, FREQUENCY (Hz)
Figure 8. Error Amp Open Loop Gain and
Phase versus Frequency
180
10 M
1.2
VCC = 15 V
1.0
0.8 TA = 25°C
0.6
TA = 125°C
0.4 TA = −55°C
0.2
0
0 2.0 4.0 6.0 8.0
VO, ERROR AMP OUTPUT VOLTAGE (V)
Figure 9. Current Sense Input Threshold
versus Error Amp Output Voltage
0
−4.0
−8.0
−12
−16
−20
−24
0
VCC = 15 V
TA = 125°C
TA = 55°C
TA = 25°C
20 40 60 80 100
Iref, REFERENCE SOURCE CURRENT (mA)
Figure 10. Reference Voltage Change
versus Source Current
120
110
VCC = 15 V
RL ≤ 0.1 W
90
70
50
−55 −25 0 25 50 75 100 125
TA, AMBIENT TEMPERATURE (°C)
Figure 11. Reference Short Circuit Current
versus Temperature
VCC = 15 V
IO = 1.0 mA to 20 mA
TA = 25°C
VCC = 12 V to 25 V
TA = 25°C
2.0 ms/DIV
Figure 12. Reference Load Regulation
2.0 ms/DIV
Figure 13. Reference Line Regulation
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6 Page | |||
ページ | 合計 : 18 ページ | ||
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PDF ダウンロード | [ UC2843A データシート.PDF ] |
データシートを活用すると、その部品の主な機能と仕様を詳しく理解できます。 ピン構成、電気的特性、動作パラメータ、性能を確認してください。 |
部品番号 | 部品説明 | メーカ |
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UC2843A | (UC2842A - UC2845A) HIGH PERFORMANCE CURRENT MODE PWM CONTROLLER | ST Microelectronics |
UC2843A | (UC2842A / UC2843A) HIGH PERFORMANCE CURRENT MODE CONTROLLERS | Motorola Semiconductors |
UC2843A | High Performance Current Mode Controllers | ON Semiconductor |