zxct1011 Zetex Semiconductors plc., zxct1011 Datasheet - Page 5

• Manufacturer Part Number: zxct1011
• Description: Zxct1011 - High-side Low Drift Current Monitor
• Manufacturer: Zetex Semiconductors plc.

Pin description
Application information
Design example
The following lines describe how to scale a load current to an output voltage.
Note: Iq is embedded into the specification of the ZXCT1011 and therefore appears an offset error.
The output current of the ZXCT1011 is directly related to the size of the trimming resistor used. It
is important to ensure the tolerance of R
1% change in output.
Consider the following: -
Issue 1- July 2005
© Zetex Semiconductors plc 2005
Pin no.
1
2
3
4
5
Defining then
since
Pin name
V
V
R
sense+
N/C
sense-
I
shunt
out
Pin function
No connection
Output current - follows transconductance of sense voltage g
for R
Trimming resistor Input. - used to trim gain value 60
Low side current sense input. – connect to load/battery etc. Must be
lower than V
without additional series resistor.
High side current sense input. – Connect to supply rail. Must be
higher than V
shunt
=120
V
I
g
I
∴
out
out
m
sense
sense+
V
sense+
= 1.2 / R
out
= Iq + V
shunt
= Iq + [ (V
= Iq + [ (1.2 x I
= (R
= (V
for correct operation. Cannot be grounded
for correct operation.
is considered. A 1% change in R
out
shunt
sense+
sense
5
x I
sense
offset
x g
) - (V
m
load
) + [(1.2 x R
x 1.2) / R
sense-
x R
) = I
sense
shunt
out
load
/ R
]
x I
shunt
x R
load
sense
) ]
x R
ZXCT1011
R
shunt
www.zetex.com
sense
shunt
m
= 10mA/V
will cause a
) / R
240
shunt
]