参数资料
型号: UC3845NG
厂商: ON Semiconductor
文件页数: 13/16页
文件大小: 0K
描述: IC REG CTRLR PWM CM 8-DIP
产品变化通告: Product Discontinuation 15/May/2006
标准包装: 50
PWM 型: 电流模式
输出数: 1
频率 - 最大: 60kHz
占空比: 50%
电源电压: 7.6 V ~ 30 V
降压:
升压:
回扫:
反相:
倍增器:
除法器:
Cuk:
隔离:
工作温度: 0°C ~ 70°C
封装/外壳: 8-DIP(0.300",7.62mm)
包装: 管件
其它名称: UC3845NGOS
UC3844, UC3845, UC2844, UC2845
V in = 15V
UC3845
7(12)
+
47
Output Load Regulation
(open loop configuration)
8(14)
2.5V
R
Internal
Bias
Reference
Regulator
+
V CC
UVLO
+
?
+
?
34V
7(11)
1N5819
I O (mA)
0
2
9
18
36
V O (V)
29.9
28.8
28.3
27.4
24.4
1N5819
V O = 2.5
R2
10k
4(7)
1.0nF
2(3)
1(1)
R
+
?
Error
Amplifier
Oscillator
+
0.5mA
2R
R
+ ?
3.6V V ref
? UVLO
?
+
1.0V
Current Sense
Comparator
T
S
R
Q
PWM
Latch
6(10)
5(8)
3(5)
15 10
+
Connect to
Pin 2 for
closed loop
operation.
R2
+1
R2
R1
+
47
V O   2 (V in )
5(9)
The capacitor’s equivalent series resistance must limit the Drive Output current to 1.0 A. An additional series
resistor may be required when using tantalum or other low ESR capacitors. The converter’s output can provide
excellent line and load regulation by connecting the R2/R1 resistor divider as shown.
Figure 31. Step ? Up Charge Pump Converter
V in = 15V
UC3845
7(12)
+
47
8(14)
Reference
+
34V
2.5V
R
Internal
Bias
Regulator
+
V CC
UVLO
?
+
?
7(11)
V O   ? (V in )
10k
4(7)
1.0nF
2(3)
1(1)
R
+
?
Error
Amplifier
Oscillator
+
0.5mA
2R
R
3.6V
1.0V
+ ?
?
?
+
V ref
UVLO
T
S
R
Q
PWM
Latch
6(10)
+
5(8)
3(5)
15
10
1N5819
+
1N5819 47
Output Load Regulation
I O (mA) V O (V)
Current Sense
Comparator
5(9)
The capacitor’s equivalent series resistance must limit the Drive Output current to 1.0 A.
An additional series resistor may be required when using tantalum or other low ESR capacitors.
Figure 32. Voltage ? Inverting Charge Pump Converter
http://onsemi.com
13
0
2
9
18
32
?14.4
?13.2
?12.5
?11.7
?10.6
相关PDF资料
PDF描述
UCC28250PW IC REG CTRLR PWM CM/VM 20-TSSOP
UCC2893D IC REG CTRLR FLYBK ISO CM 16SOIC
UCC3957MTR-2G4 IC LI-ION PROTECT CIRCUIT 16QSOP
UDN2982LWTR-T IC SOURCE DRIVER 8CHAN 20-SOIC
UDN2987LW-6-T IC SOURCE DRIVER 8CHAN 20-SOIC
相关代理商/技术参数
参数描述
UC3845NG4 功能描述:电流型 PWM 控制器 Current-Mode PWM Controller RoHS:否 制造商:Texas Instruments 开关频率:27 KHz 上升时间: 下降时间: 工作电源电压:6 V to 15 V 工作电源电流:1.5 mA 输出端数量:1 最大工作温度:+ 105 C 安装风格:SMD/SMT 封装 / 箱体:TSSOP-14
UC3845P 制造商:Texas Instruments 功能描述:Swithed-Mode Power Supply Controller, Current Mode Type, Bi-Polar, 8 Pin, Plastic, DIP
UC3845Q 制造商:未知厂家 制造商全称:未知厂家 功能描述:Current-Mode SMPS Controller
UC3845QTR 制造商:未知厂家 制造商全称:未知厂家 功能描述:Current-Mode SMPS Controller
UC3845-S08-R 制造商:UTC-IC 制造商全称:UTC-IC 功能描述:HIGH PERFORMANCE CURRENT MODE PWM CONTROLLERS