HA17432VUP 查看數據表（PDF） - Hitachi -> Renesas Electronics
零件编号
产品描述 (功能)
比赛名单
HA17432VUP Datasheet PDF : 26 Pages
| |||
HA17431 Series
Application Hints (cont.)
No. Application Example
6
Constant voltage regulator circuit
VCC
R1
Q
Vout
R2
GND
Cf
R3
GND
7
Discharge type constant current circuit
VCC
R
Q
GND
2.5 V
RS
+
IL
–
8
Induction type constant current circuit
+
VCC
R
IL
–
Q
GND
2.5 V
RS
Description
This is a 3-pin regulator with a discrete configuration, in
which the output voltage
Vout = 2.5 V × (R2 + R3)
R3
R1 is a bias resistance for supplying the HA17431
cathode current and the output transistor Q base
current.
This circuit supplies a constant current of
IL ≅
2.5 V
RS
[A] into the load. Caution is required
since the HA17431 cathode current is also
superimposed on IL.
The requirement in this circuit is that the cathode
current must be greater than Imin = 1 mA. The IL
setting therefore must be on the order of several mA or
more.
In this circuit, the load is connected on the collector
side of transistor Q in circuit 7 above. In this case, the
load floats from GND, but the HA17431 cathode current
is not superimposed on I , so that I can be kept small
L
L
(1 mA or less is possible). The constant current value
is the same as for circuit 7 above:
IL ≅
2.5 V
RS
[A]
Rev.1, Sep. 2002, page 16 of 24
Share Link: 