参数资料
型号: UC3845NG
厂商: ON Semiconductor
文件页数: 6/16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
25
V CC = 30 V
C L = 15 pF
T A = 255C
20
15
10
5
R T = 10 k
C T = 3.3 nF
V FB = 0 V
I Sense = 0 V
T A = 255C
100 ns/DIV
0
0
10
20 30
40
V CC , SUPPLY VOLTAGE (V)
Figure 14. Output Cross Conduction
Figure 15. Supply Current versus
Supply Voltage
PIN FUNCTION DESCRIPTION
Pin
8 ? Pin
1
2
3
4
5
6
7
8
?
?
?
?
14 ? Pin
1
3
5
7
?
10
12
14
8
11
9
2,4,6,13
Function
Compensation
Voltage
Feedback
Current Sense
R T /C T
GND
Output
V CC
V ref
Power Ground
V C
GND
NC
Description
This pin is Error Amplifier output and is made available for loop compensation.
This is the inverting input of the Error Amplifier. It is normally connected to the switching
power supply output through a resistor divider.
A voltage proportional to inductor current is connected to this input. The PWM uses this
information to terminate the output switch conduction.
The Oscillator frequency and maximum Output duty cycle are programmed by connecting
resistor R T to V ref and capacitor C T to ground. Operation to 1.0 MHz is possible.
This pin is combined control circuitry and power ground (8 ? pin package only).
This output directly drives the gate of a power MOSFET. Peak currents up to 1.0 A are
sourced and sunk by this pin. The output switches at one ? half the oscillator frequency.
This pin is the positive supply of the control IC.
This is the reference output. It provides charging current for capacitor C T through resistor R T .
This pin is a separate power ground return (14 ? pin package only) that is connected back to
the power source. It is used to reduce the effects of switching transient noise on the control
circuitry.
The Output high state (V OH ) is set by the voltage applied to this pin (14 ? pin package only).
With a separate power source connection, it can reduce the effects of switching transient
noise on the control circuitry.
This pin is the control circuitry ground return (14 ? pin package only) and is connected to back
to the power source ground.
No connection (14 ? pin package only). These pins are not internally connected.
http://onsemi.com
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