欢迎访问ic37.com |
会员登录 免费注册
发布采购

MC33154P 参数 Datasheet PDF下载

MC33154P图片预览
型号: MC33154P
PDF下载: 下载PDF文件 查看货源
内容描述: 单IGBT大电流栅极驱动器 [SINGLE IGBT HIGH CURRENT GATE DRIVER]
分类和应用: 驱动器MOSFET驱动器栅极驱动程序和接口接口集成电路光电二极管双极性晶体管栅极驱动
文件页数/大小: 12 页 / 201 K
品牌: MOTOROLA [ MOTOROLA ]
 浏览型号MC33154P的Datasheet PDF文件第4页浏览型号MC33154P的Datasheet PDF文件第5页浏览型号MC33154P的Datasheet PDF文件第6页浏览型号MC33154P的Datasheet PDF文件第7页浏览型号MC33154P的Datasheet PDF文件第8页浏览型号MC33154P的Datasheet PDF文件第10页浏览型号MC33154P的Datasheet PDF文件第11页浏览型号MC33154P的Datasheet PDF文件第12页  
MC33154  
An active high output, resistor, and small signal diode  
provide an excellent LED driver. This circuit is shown in  
Figure 28.  
voltage on the desaturation input. The voltage reference is  
set to about 6.5 V. This will allow a maximum ON–voltage of  
about 5.0 V.  
Figure 28. Output Fault Optoisolator  
Figure 29. Desaturation Detection Using a Diode  
Short Circuit  
Latch Output  
V
CC  
V
CC  
V
CC  
Desaturation  
Comparator  
1.0 mA  
D1  
Q
8
7
6.5 V  
V
Kelvin  
Gnd  
EE  
V
EE  
V
EE  
Kelvin  
Gnd  
UNDER VOLTAGE LOCK OUT  
A fault exists when the gate input is high and V  
of the  
.The  
CE  
IGBT is greater than the maximum allowable V  
CE(sat)  
It is desirable to protect an IGBT from insufficient gate  
voltage. IGBTs require 15 V on the gate to guarantee device  
saturation. At gate voltages below 13 V, the “on” state voltage  
increases dramatically, especially at higher currents. At very  
lower gate voltages, below 10 V, the IGBT may operate in the  
linear region and quickly overheat. Many PWM motor drives  
use a bootstrap supply for the upper gate drive. The UVLO  
provides protection for the IGBT in case the bootstrap  
capacitor discharges.  
output of the desaturation comparator is ANDed with the gate  
input signal and fed into the Short Circuit (SC) latch. The SC  
latch will turn–off the IGBT for the remainder of the cycle  
when a fault is detected. When the input is toggled low, the  
latch will reset. The reference voltage is tied to the Kelvin  
Ground instead of the V to make the threshold  
EE  
independent of negative gate bias.  
The MC33154 also features a programmable turn–on  
blanking time. During turn–on the IGBT must clear the  
opposing free wheeling diode. The collector voltage will  
remain high until the diode is cleared. Once the diode has  
been cleared the voltage will come down quickly to the  
The MC33154 will typically start up at about 12 V. The  
UVLO circuit has about 1.0 volt of hysteresis. The UVLO will  
disable the output if the supply voltage falls below about 11 V.  
V
of the device. Following turn–on there is normally  
CE(sat)  
PROTECTION CIRCUITRY  
Desaturation Protection  
considerable ringing on the collector due to the C  
IGBTs and the parasitic wiring inductance.  
of the  
oss  
The error signal from the desaturation signal must be  
blanked out sufficiently to allow the diode to be cleared and  
the ringing to settle out.  
The blanking function uses an NPN transistor to clamp the  
comparator input when the gate input is low. When the input  
is switched high, the clamp transistor will turn–off, and the  
current source will charge up the blanking capacitor. The time  
required for blanking capacitor to charge up from the  
on–voltage of the clamp FET to the trip voltage of the  
comparator is the blanking time.  
Bipolar Power circuits have commonly used what is known  
as “Desaturation Detection”. This involves monitoring the  
collector voltage and turning off the device if the collector  
voltage rises above a certain limit. A bipolar transistor will  
only conduct a certain amount of current for a given base  
drive. When the base is overdriven the device is in saturation.  
When the collector current rises above the knee, the device  
pulls out of saturation.  
The maximum current the device will conduct in the linear  
region is a function of the base current and hfe of the  
transistor.  
The output characteristics of an IGBT are similar to a  
Bipolar device. However the output current is a function of  
gate voltage, not current. The maximum current depends on  
the gate voltage and the device. IGBTs tend to have a very  
high transconductance and a much higher current density  
under a short circuit than a bipolar device.  
If a short circuit occurs after the IGBT is turned on and  
saturated, the delay time will be the time required for the  
current source to charge up the blanking capacitor from the  
V
to the trip voltage of the comparator.  
CE(sat)  
Sense IGBT Protection  
Another approach to protecting the IGBTs is to sense the  
emitter current using a current shunt or Sense IGBTs.  
This method has the advantage of being able to use high  
gain IGBTs which do not have any inherent short circuit  
capability.  
Current sense IGBTs work as well as current sense  
MOSFETs in most circumstances. However, the basic  
problem of working with very low sense voltages still exists.  
Sense IGBTs sense current through the channel and are  
therefore linear concerning collector current.  
Motor control IGBTs are designed for a lower current  
density under shorted conditions and a longer short circuit  
survival time.  
The best method for detecting desaturation is the use of a  
high voltage clamp diode and a comparator. The MC33154  
has a desaturation comparator which senses the collector  
voltage and provides an output indicating when the device is  
not full saturated. Diode D1 is an external high voltage diode  
with a rated voltage comparable to the power device. When  
the IGBT is ON and saturated, diode D1 will pull down the  
voltage on the desaturation input. When the IGBT is OFF or  
pulls out of saturation, the current source will pull up the  
Because IGBTs have a very low incremental  
on–resistance, sense IGBTs behave much like low–on  
resistance current sense MOSFETs. The output voltage of a  
9
MOTOROLA ANALOG IC DEVICE DATA