ZXCT1030
Voltage output Current Monitor
Com parator
Referring to the block diagram , the current m onitor The open collector output is active low and is asserted
takes the sm all voltage developed across the sense when Vsense x 10 (Vout) > Vcom p_in.
resistor (Vsense) and transfers it from the large
com m on m ode supply voltage to a ground-referenced
signal with a gain of 10. The sense input com m on
m ode range is 2v to 20v. In this range, a linear output
voltage is delivered.
It can be connected to any voltage rail up to Vin via a
pull-up resistor. Suggest values for the resistor are in
the range of 10-100k⍀.
In the case where high load currents or a short circuit
occurs, thus reducing the com m on m ode signals (V+,
V-) typically below 2.6V, the com parator will default to
the asserted state. This can elim inate a closed loop
system ‘latch-up’ condition, allowing the controller to
rem ove the applied power.
Reference
The bandgap reference allows the com parator to
com pare the translated Vsense with a threshold value
chosen by the user which can be any voltage from 0 to
1.22V, configured by two external resistors which
form s Vcom p_in.
Pin Na m e
Vcc
Pin Fu n ct io n
PIN CONNECTIONS
S u p p ly vo lta g e
Ne g a tive s e n s e in p u t
Po s itive s e n s e in p u t
Gro u n d
S e n s e -
S e n s e +
GND
MSOP8
Co m p _in
Co m p a ra to r in p u t, u s u a lly a
ra tio o f th e re fe re n ce o r
o th e r co n tro l s ig n a l.
V
8
7
6
5
Com p
1
2
3
4
cc
out
Re f_o u t
Vo u t
Re fe re n ce o u tp u t
Sense-
Sense+
GND
V
out
Cu rre n t Mo n ito r o u tp u t
vo lta g e
Ref
out
Co m p _o u t
Op e n co lle cto r co m p a ra to r
o u tp u t
Com p
in
PROVISIONAL ISSUE A - J UNE 2002
4
