ISL6209
shoot-through circuitry determines the lower gate delay time
t PDHLGATE . The upper MOSFET gate-to-source voltage is
monitored, and the lower gate is allowed to rise, after the
upper MOSFET gate-to-source voltage drops below 1V. The
lower gate then rises [t RLGATE ], turning on the lower
by the addition or removal of the additional dead-time. Refer
to Figure 3 and Figure 4 for more detail.
FCCM = VCC or GND
MOSFET.
This driver is optimized for converters with large step down
ratio, such as those used in a mobile-computer core voltage
regulator. The lower MOSFET is usually sized much larger.
This driver is optimized for converters with large step down
compared to the upper MOSFET because the lower
MOSFET conducts for a much longer time in a switching
period. The lower gate driver is therefore sized much larger
to meet this application requirement. The 0.4 Ω on-resistance
and 4A sink current capability enable the lower gate driver to
absorb the current injected to the lower gate through the
drain-to-gate capacitor of the lower MOSFET and prevent a
shoot through caused by the high dv/dt of the phase node.
Three-State PWM Input
A unique feature of the ISL6209 and other Intersil drivers is
the addition of a shutdown window to the PWM input. If the
PWM signal enters and remains within the shutdown window
for a set holdoff time, the output drivers are disabled and
both MOSFET gates are pulled and held low. The shutdown
state is removed when the PWM signal moves outside the
shutdown window. Otherwise, the PWM rising and falling
thresholds outlined in the ELECTRICAL SPECIFICATIONS
determine when the lower and upper gates are enabled.
1V
1V
GATE A
GATE A
GATE B
Adaptive Shoot-Through Protection
FCCM = RESISTOR to VCC or GND
GATE B
Adaptive Protection with Delay
t delay = 5n - 50ns
During start-up, PWM should be in the three-state position
(1/2 V CC ) until actively driven by the controller IC.
Shoot-Through Protection
The ISL6209 driver delivers shoot-through protection by
incorporating gate threshold monitoring and programmable
dead-time to prevent upper and lower MOSFETs from
conducting simultaneously, thereby shorting the input supply
4
50
45
40
35
FIGURE 3. PROGRAMMABLE DEAD-TIME
to ground. Gate threshold monitoring ensures that one gate
is OFF before the other is allowed to turn ON.
During turn-off of the lower MOSFET, the LGATE voltage is
monitored until it reaches a 1V threshold, at which time the
UGATE is released to rise. Internal circuitry monitors the
upper MOSFET gate-to-source voltage during UGATE
turn-off. Once the upper MOSFET gate-to-source voltage
has dropped below a threshold of 1V, the LGATE is allowed
to rise.
30
25
20
15
10
5
0
t DELAY
0
50
100
150
200
250
300
In addition to gate threshold monitoring, a programmable
delay between MOSFET switching can be accomplished by
placing a resistor from the DELAY pin to ground. This delay
allows for maximum design flexibility over MOSFET
selection. The delay can be programmed from 5ns to 50ns. If
not desired, the DELAY pin must be tied to VCC to disable
the delay circuitry. Gate threshold monitoring is not affected
6
R DELAY (k Ω )
FIGURE 4. ADDITIONAL PROGRAMMED DEAD-TIME
( t DELAY ) vs DELAY RESISTOR VALUE
相关PDF资料
ISL6210CRZ IC MOSFET DRIVER DUAL SYNC 16QFN
ISL6244EVAL1 EVALUATION BOARD ISL6244
ISL6261AEVAL1Z EVAL BOARD 1 FOR ISL6261A
ISL6261EVAL1Z EVAL BOARD FOR ISL6261 1 QFN
ISL6271AEVAL1 EVALUATION BOARD FOR ISL6271A
ISL62882CEVAL2Z EVAL BOARD FOR ISL62882C
ISL62883CEVAL2Z EVAL BOARD FOR ISL62883C
ISL62883EVAL2Z EVALUATION BOARD FOR ISL62883
相关代理商/技术参数
ISL6209CBZ 功能描述:功率驱动器IC P6 HV SYNCHCT BUCK MSFT W/POR & DELAY RoHS:否 制造商:Micrel 产品:MOSFET Gate Drivers 类型:Low Cost High or Low Side MOSFET Driver 上升时间: 下降时间: 电源电压-最大:30 V 电源电压-最小:2.75 V 电源电流: 最大功率耗散: 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:SOIC-8 封装:Tube
ISL6209CBZ-T 功能描述:功率驱动器IC P6 HV SYNCHCT BUCK MSFT W/POR & DELAY RoHS:否 制造商:Micrel 产品:MOSFET Gate Drivers 类型:Low Cost High or Low Side MOSFET Driver 上升时间: 下降时间: 电源电压-最大:30 V 电源电压-最小:2.75 V 电源电流: 最大功率耗散: 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:SOIC-8 封装:Tube
ISL6209CR 制造商:Rochester Electronics LLC 功能描述:- Bulk
ISL6209CR-T 制造商:INTERSIL 制造商全称:Intersil Corporation 功能描述:High Voltage Synchronous Rectified Buck MOSFET Driver
ISL6209CRZ 制造商:INTERSIL 制造商全称:Intersil Corporation 功能描述:High Voltage Synchronous Rectified Buck MOSFET Driver
ISL6209CRZ-T 制造商:INTERSIL 制造商全称:Intersil Corporation 功能描述:High Voltage Synchronous Rectified Buck MOSFET Driver
ISL6210 制造商:INTERSIL 制造商全称:Intersil Corporation 功能描述:Dual Synchronous Rectified MOSFET Drivers
ISL6210CRZ 功能描述:IC MOSFET DRIVER DUAL SYNC 16QFN RoHS:是 类别:集成电路 (IC) >> PMIC - MOSFET,电桥驱动器 - 外部开关 系列:- 标准包装:50 系列:- 配置:高端 输入类型:非反相 延迟时间:200ns 电流 - 峰:250mA 配置数:1 输出数:1 高端电压 - 最大(自引导启动):600V 电源电压:12 V ~ 20 V 工作温度:-40°C ~ 125°C 安装类型:通孔 封装/外壳:8-DIP(0.300",7.62mm) 供应商设备封装:8-DIP 包装:管件 其它名称:*IR2127