TOP252-262
电压监测(V)和外部流限(X)引脚的典型使用方法（继上）
+
+
VUV = RLS × IUV + VV (IV = IUV
)
VOV = IOV × RLS + VV (IV = IOV
)
4 M7
4 M7
For Values Shown
VUV = 103.8 VDC
For Values Shown
VOV = 457.2 VDC
RLS
R
LS
DC
Input
Voltage
DC
Input
Voltage
40 k7
55 k7
1N4148
D
V
D
S
V
CONTROL
CONTROL
C
C
6.2 V
S
-
-
PI-4720-120307
PI-4721-120307
图 20. 仅实现欠压的线电压检测（过压禁止）
图 21. 仅实现过压的线路检测（禁止欠压）。低压时会降低最大占空比，
线电压增高时最大占空比进一步降低
+
+
ILIMIT = 100% @ 100 VDC
53% @ 300 VDC
For RIL = 12 k7
ILIMIT
=
ILIMIT = 61%
RLS
2.5 M7
TOP259-261YN would
use the G pin as the
return for RIL.
For RIL = 19 k7
ILIMIT = 37%
See Figure 55b for other
resistor values (RIL).
DC
Input
Voltage
DC
Input
Voltage
D
S
D
CONTROL
X
CONTROL
C
C
TOP259-261YN would
use the G pin as the
return for RIL.
S
X
RIL
RIL
6 k7
-
-
PI-4723-011008
PI-4722-021308
图 22. 外部设定流限
图 23. 流限随电压降低而降低
+
+
QR can be an optocoupler
output or can be replaced
by a manual switch.
QR can be an optocoupler
output or can be replaced by
a manual switch.
TOP259-261YN would
use the G pin as the
return for QR.
For RIL =12 k7
ILIMIT = 61%
DC
Input
Voltage
DC
Input
Voltage
D
S
D
S
For RIL = 19 k7
CONTROL
CONTROL
ILIMIT = 37%
C
C
TOP259-261YN would
use the G pin as the
return for QR.
X
X
RIL
ON/OFF
QR
QR
ON/OFF
47 K7
-
16 k7
-
PI-2625-011008
PI-4724-011008
图 25. 使用外部流限设定来启动远程开／关
图 24. 启动远程开／关
17
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版本D 08/08
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