APX6223 Datasheet, PDF (11/16 Pages) Anpec Electronics Coropration – DSC Motors Driver IC

APX6223
Function Descriptions (Cont.)
Constant Current H-Bridge (Channel 6) (Cont.)
current about 200mA=0.2V/1Ω is limited by VC6
voltage. When the setup value of the weak excitation
mode is changed, add a variable resistor between VC6
and VC6A pin to adjust the current limit (V set to
REFCT
“H”), for example, if VC6 & VC6A pin add a variable
resistor and the value is 20KΩ, since this 20KΩ is
parallel with another 20KΩ, the equal resistor value is
10KΩ. So VC6 will be equal 1.2V x 10/(100+10) = 0.11V,
the current limit is equal 0.11V/1Ω = 110mA. AD/A
value direct connects to VC6 (V_REFCT to “L”) is another
method to control the current limit as well.
VREF(1.2V)
100KΩ
20KΩ
Hi: ON
Low: OFF
VC6
20KΩ
VC6A
VREFCT
DGND
Constant
current
H bridge
(CH6)
RNF6
1Ω
Figure2. Constant Current Control Setting
Copyright © ANPEC Electronics Corp.
11
Rev. A.2 - Jul., 2005
www.anpec.com.tw