Diodes ZXCT1011 User Manual

ZXCT1011
High-side low drift current monitor

Description

The ZXCT1011 is a high side current sense monitor. Using this type of device eliminates the need
to disrupt the ground plane when sensing a load current.

The ZXCT1011 takes the voltage developed across a current shunt resistor and translates it into a
proportional output current.

A user defined output resistor scales the output current into a ground referenced voltage.

A current reference resistor, external to the IC, results in an improved temperature coefficient
compared to the ZXCT1009.

The wide input voltage range of 20V down to as low as 2.5V make it suitable for a range of
applications. With a minimum operating current of just 4uA, combined with its SOT23-5 package
make it suitable for portable battery equipment too.

Features

■ Accurate high-side current sensing

■ 2.5V to 20V supply range

■ 4 µA quiescent current

■ 1% typical accuracy

■ Package SOT23-5

Applications

■ Automotive current measurement

■ Battery management

■ DC motor and solenoid control

■ Over current monitor

■ Power management

■ Temperature range -40 to 125°C

Typical application circuit Pin connections

Vin

R

sense

Load

N/C

R

shunt

120 Ω

GND

5

V

sense+

ZXCT1011

3

I

out

2

V

Rout

4

sense-

I

out

R

shunt

V

V

sense+

V

sense-

Ordering information

Order code Pack Part

mark

ZXCT1011E5TA SOT23-5 1011 7 (180) 8mm 3,000

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© Zetex Semiconductors plc 2005

Reel Size

inches (mm)

Tape width Quantity Per

reel

Absolute maximum ratings

ZXCT1011

V

sense+

Voltage on any pin 0.6V and V

V

sense+

to V

2.5V

sense-

20 V

sense+

+0.5V

Operating temperature -40 to 125°C

Storage temperature -55 to 150°C

Maximum junction temperature 150°C

Package power dissipation 300mW at T

= 25°C (De-rate to zero at 150°C)

A

Operation above the absolute maximum rating may cause device failure. Operation at the
absolute maximum ratings, for extended periods, may reduce device reliability.

Electrical characteristics

Test conditions TA = 25°C, Vin = 5V, R

Symbol Parameter Conditions Min Typ. Max Units

*

V

in

I

out

V

sense

I

sense -

Supply range - 2.5 - 20 V

Output current V

Sense voltage

V

input current - - - 100 nA

sense-

†

Acc Accuracy R

g

m

Tc

BW

Transconductance
I

out/Vsense

Temperature coefficient

**

Bandwidth V

‡

PSSR Supply rejection V

shunt

sense

= 120⍀. V

= 0V
=10mV

=30mV
=100mV
=200mV
=500mV

=100mV. Unless otherwise stated.

sense

1

84

273

0.97

1.95

4.85

4
116
320

1.00

2.00

5.00

15
124
330

1.03

2.05

5.15

µA
µA
µA

mA
mA
mA

- 0 - 500 mV

= 0.1⍀

sense

V

= 100mV

sense

R

= 120⍀ -10- mA/V

shunt

-3 - 3 %

- - 30 150 ppm/° C

= 10mV

sense

CL = 5pF, R

= 100mV

V

sense

CL = 5pF, R

= 200mV, R

sense

out

out

-400

= 1k⍀

1.5

= 1k⍀

=1k⍀ -68- dB

out

-kHz

MHz

NOTES:

*V
†V
‡ Temperature dependent measurements are extracted from characterization and simulation results.
** Where CL is the capacitance across R

sense+

sense

relative to I

= (V

sense+

out

) - (V

.

sense-

).

.

out

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© Zetex Semiconductors plc 2005

Typical characteristics

ZXCT1011

TA=25°C, R

= 120 unless otherwise stated.

shunt

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© Zetex Semiconductors plc 2005