Diodes ZXCT1020 - Manual (Page 2)

ZXCT1020
Issue 1 - August 2007 2 www.zetex.com
© Zetex Semiconductors plc 2007
Absolute maximum ratings
NOTES:
(a) Subject to V
SENSE
+ never going 6V below V
B
.
(b) Subject to absolute maximum V
SENSE
not being exceeded.
(c) V
SENSE
is defined as the voltage difference across the sense resistor. and is the voltage across resistor R
SH
plus the
voltage between S+ and S-.
(d) V
SENSE
might need to be reduced when used with smaller values of R
SH
and at larger rails due to increased power dissipation.
Pin out information
Recommended operating conditions
Recommended resistor gain setting combinations
Voltage on V
B
with respect to GND pin -0.5V to 20V
Voltage on S+ (a) , S- (b) , OUT with respect to GND pin -0.5V to V
B
+0.5V
V
SENSE
(c) -0.5V to +2.5V (d)
Junction temperature -40°C to125°C
Storage temperature -55°C to 150°C
Package power dissipation (T
amb
= 25°C) SOT23-5 300mW
Pin Name Pin function
1 S+ Positive sense input. Should be tied to positive side of sense resistor via
resistance (R
SH
) of the order of 150
⍀ to 1.5k⍀.
2 GND Ground and substrate connection of device.
3 OUT Current output. A gain setting resistor (R
G
) referenced to GND should be
connected to this pin to set overall voltage gain of:
Gain = R
G
/R
SH
The resistance, R
G
, placed on out will set the ZXCT1020 output impedance equal
to R
G
. When driving low impedance loads both R
G
and R
SH
should be reduced.
4 V
B
Input voltage pin. Provides bias to current monitor and should be tied to the
rail whose current is being monitored.
5 S- High impedance negative sense voltage input
Parameter Min. Max. Units
V
SENSE+
Common-mode sense input range 2.5 20 V
V
B
Bias pin input voltage range (*)
NOTES:
(*) For best performance V
B
and V
SENSE+
should be referred to the rail whose current is being measured.
2.5 20 V
V
SENSE
Differential sense Input voltage range 0 1.5 V
V
OUT
Output voltage range 0 V
SENSE-
- 1 V
R
SH
Shunt resistor value 120 2000
⍀
T
A
Ambient temperature range -40 85 °C
Gain R
SHUNT
R
GAIN
10 1.5k ⍀ 15k ⍀
20 750
⍀
15k
⍀
50 300
⍀
15k
⍀
100 150 ⍀ 15k ⍀