參數(shù)資料
型號: MIC5021BM
廠商: MICREL INC
元件分類: 功率晶體管
英文描述: Replaced by PTN78060W :
中文描述: BUF OR INV BASED MOSFET DRIVER, PDSO8
封裝: SOIC-8
文件頁數(shù): 8/9頁
文件大?。?/td> 132K
代理商: MIC5021BM
MIC5021
Micrel
5-176
October 1998
External Protection
Resistors placed in series with each
SENSE
connection limit
the current drawn from the internal Schottky diodes during a
negative transient. This minimizes the forward drop across
the diodes.
V
DD
Input
C
T
Gnd
V
BOOST
Gate
Sense
Sense
+
N-Channel
Power MOSFET
MIC5021
1
2
3
4
8
7
6
5
R
S
L
5μA
V
R1
15μA
V
R2
R1
R2
V
R1
= V
R2
to avoid skewing
the 50mV trip point.
.
(5mV suggested)
R1
3
×
R2
50mV nominal
(at trip)
Figure 7. Resistor Voltage Drop
During normal operation, sensing current from the sense pins
is unequal (5
μ
A and 15
μ
A). The internal Schottky diodes are
reverse biased and have no effect. To avoid skewing the trip
voltage, the current limiting resistors must drop equal volt-
ages at the trip point currents. See Figure 7. To minimize
resistor tolerance error, use a voltage drop lower than the trip
voltage of 50mV. 5mV is suggested.
External Schottky diodes are also recommended. See D2
and D3 in Figure 8. The external diodes clamp negative
transients better than the internal diodes because their larger
size minimizes the forward voltage drop at higher currents.
V
DD
Input
C
T
Gnd
V
BOOST
Gate
Sense
Sense
TTL Input
Inductive
Load
N-Channel
Power MOSFET
+12V to +36V
MIC5021
1
2
3
4
8
6
5
10μF
2.7
nF
R1
R
SENSE
1.0k
330
R2
D2
11DQ03
D3
11DQ03
D1
Figure 8. Protection from Inductive Kick
High-Side Sensing
Sensing the current on the high side of the MOSFET isolates
the
SENSE
pins from the inductive spike.
V
DD
Input
C
T
Gnd
V
BOOST
Gate
Sense
Sense
TTL Input
Wirewound
Resistor
(3
)
N-Channel
Power MOSFET
(IRFZ44)
+12V to +20V
R
(< 0.01
)
(+12V)
MIC5021
1
2
3
4
8
7
6
5
10μF
0.01
μF
Figure 9. High Side Sensing
Lamp Driver Application
Incandescent lamps have a high inrush current (low resis-
tance) when turned on. The MIC5021 can perform a “soft
start” by pulsing the MOSFET (overcurrent condition) until
the filament is warm and its current decreases (resistance
increases). The sense resistor value is selected so the
voltage drop across the sense resistor decreases below the
sense threshold (50mV) as the filament becomes warm. The
FET is no longer pulsed and the lamp turns completely on.
V
DD
Input
C
T
Gnd
V
BOOST
Gate
Sense
Sense
+
TTL Input
R
(0.041
)
N-Channel
Power MOSFET
(IRF540)
V+
MIC5021
1
2
3
4
8
7
6
5
10μF
0.01
μF
Incandescent
Lamp (#1157)
(+12V)
"( )" values apply to demo circuit.
See text.
Figure 10. Lamp Driver with
Current Sensing
A lamp may not fully turn on if the filament does not heat up
adequately. Changing the duty cycle, sense resistor, or both
to match the filament characteristics can correct the problem.
Soft start can be demonstrated using a #1157 dual filament
automotive lamp. The value of R
S
shown in Figure 10 allows
for soft start of the higher-resistance filament (measures
approx. 2.1
cold or 21
hot).
相關(guān)PDF資料
PDF描述
MIC5021BN Replaced by PTN78060W :
MIC5031 High-Speed High-Side MOSFET Driver(高速高邊MOS場效應(yīng)管驅(qū)動器)
MIC5031BM High-Speed High-Side MOSFET Driver
MIC50398 Replaced by PTN78060W,PTN78060H :
MIC50398CN Replaced by PTN78060W,PTN78060H :
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
MIC5021BM TR 功能描述:IC DRIVER MOSFET HISIDE HS 8SOIC RoHS:否 類別:集成電路 (IC) >> PMIC - MOSFET,電橋驅(qū)動器 - 外部開關(guān) 系列:- 標(biāo)準(zhǔn)包裝:50 系列:- 配置:高端 輸入類型:非反相 延遲時間:200ns 電流 - 峰:250mA 配置數(shù):1 輸出數(shù):1 高端電壓 - 最大(自引導(dǎo)啟動):600V 電源電壓:12 V ~ 20 V 工作溫度:-40°C ~ 125°C 安裝類型:通孔 封裝/外殼:8-DIP(0.300",7.62mm) 供應(yīng)商設(shè)備封裝:8-DIP 包裝:管件 其它名稱:*IR2127
MIC5021BN 功能描述:IC DRIVER MOSFET HI SIDE HS 8DIP RoHS:否 類別:集成電路 (IC) >> PMIC - MOSFET,電橋驅(qū)動器 - 外部開關(guān) 系列:- 標(biāo)準(zhǔn)包裝:50 系列:- 配置:高端 輸入類型:非反相 延遲時間:200ns 電流 - 峰:250mA 配置數(shù):1 輸出數(shù):1 高端電壓 - 最大(自引導(dǎo)啟動):600V 電源電壓:12 V ~ 20 V 工作溫度:-40°C ~ 125°C 安裝類型:通孔 封裝/外殼:8-DIP(0.300",7.62mm) 供應(yīng)商設(shè)備封裝:8-DIP 包裝:管件 其它名稱:*IR2127
MIC5021YM 功能描述:功率驅(qū)動器IC High Speed High Side MOSFET Driver - Lead Free RoHS:否 制造商:Micrel 產(chǎn)品:MOSFET Gate Drivers 類型:Low Cost High or Low Side MOSFET Driver 上升時間: 下降時間: 電源電壓-最大:30 V 電源電壓-最小:2.75 V 電源電流: 最大功率耗散: 最大工作溫度:+ 85 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:SOIC-8 封裝:Tube
MIC5021YM TR 功能描述:功率驅(qū)動器IC High Speed High Side MOSFET Driver - Lead Free RoHS:否 制造商:Micrel 產(chǎn)品:MOSFET Gate Drivers 類型:Low Cost High or Low Side MOSFET Driver 上升時間: 下降時間: 電源電壓-最大:30 V 電源電壓-最小:2.75 V 電源電流: 最大功率耗散: 最大工作溫度:+ 85 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:SOIC-8 封裝:Tube
MIC5021YM 制造商:Micrel Inc 功能描述:Temperature Sensor IC 制造商:Micrel Inc 功能描述:IC, MOSFET DRIVER, HIGH SIDE, SOIC-8