ZETEX ZXCT1041 Technical data

ZXCT1041
Bidirectional precision high-side current monitor

Description

The ZXCT1041 is a bidirectional precision high­side current sense monitor. The output voltage
is proportional to the differential input voltage.
Direction of current flow is indicated by the
Flag pin.

The ZXCT1041 provides a fixed gain of 10 for
applications where minimal sense voltage is
required.

Features

• Bidirectional high side measurement

• Output voltage scaling x10

• 2.7V to 20V high side voltage

• 35µA quiescent current

• 1% typical accuracy

• SOT23-5 package

Pin connections

The very low offset voltage enables a typical
accuracy of 2% for sense voltages of only
10mV, giving better tolerances for small sense
resistors necessary at higher currents.

The wide input voltage range of 18V down to
as low as 2.7V make it suitable for a range of
applications.

A minimum operating current of just 40␮A,
combined with a SOT23-5 package makes this
part suitable for portable battery equipment.

Applications

• Battery management

• Over current monitor

• Battery gas gauging

• Motor control

Typical application circuit

R

V

+

IN

SENSE

VIN-

54

Flag

V

SENSE

V

-

SENSE

V

+

SENSE-

ZXCT1041

Flag

1

GND

V

OUT

3

V

OUT

V

OUT

V

SENSE

GND

+

2

Ordering information

Order code Package Partmark Reel size

(inches)

ZXCT1041E5TA SOT23-5 1041 7 8 3000

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Tape width

(mm)

Quantity

per reel

Absolute maximum ratings

ZXCT1041

Voltage on V

Voltage on all other pins -0.6V to (V

Vsense [(V

SENSE

Operating temperature, T

SENSE-

+) - (V

and V

SENSE

SENSE+

-)] +/-6V

A

-0.6 to 20V

-40 to 125°C

SENSE+

/ V

SENSE-

) +0.6V

Storage temperature -55 to 150°C

Maximum junction temperature, T

Package power dissipation 300mW at T

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

150°C

J

= 25°C (De-rate to zero at 150°C)

A

Recommended operating conditions

Parameter Min. Max. Units

V

SENSE±

Flag Current direction flag output 0 V

V

SENSE

V

OUT

T

A

Common-mode sense input range 2.7 20 V

SENSE±

V

Differential sense input voltage range 0 ±0.8 V

Output voltage range 0 V

SENSE±

-1.5 V

Ambient temperature range -40 125 °C

Pin function table

Pin Name Description

1 Flag This is the current direction pin. It is open collector and allows the logic high

level to be set independent of V
greater than V

SENSE-

2 GND Ground pin

3 OUT Output voltage pin

4V

SENSE+

This is the positive input of the current monitor. It also acts as the supply
voltage pin providing current for internal circuitry. The current through this
pin varies with differential sense voltage

5V

SENSE-

This is the negative input of the current monitor. The current through this
pin varies with differential sense voltage

SENSE+

voltage. Low indicates V

SENSE+

is

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Electrical characteristics

ZXCT1041

Test conditions TA = 25°C, V

SENSE

+ = 10V, V

SENSE

= 100mV

Symbol Parameter Conditions Min. Typ. Max. Units

I

Q

I

SENSE

I

SENSE

V

OUT

Ground pin current 15 35 50 µA

+V

-V

Output voltage

+ input current V

SENSE

- input current V

SENSE

SENSE

SENSE

V

SENSE

= 0V 10 17 24 µA

= 0V 10 17 24 µA

= +150mV 1.55 1.5 1.45 V

[flag high]

= +100mV 1.02 1 0.98 V

SENSE

= +30mV 309 300 291 mV

SENSE

= 0V 0 15 mV

SENSE

= -30mV 285 300 315 mV

SENSE

= -100mV 0.95 1 1.05 V

SENSE

= -150mV 1.42 1.50 1.58 V

SENSE

= ±100mV 30 ppm/ºC

SENSE

V

OUT

[flag low] V

TC V

variation with

OUT

V

V

V

V

V

V

temperature

Gain V

OUT/VSENSE

10

Accuracy Total output error

V

= 100mV -2 2 %

SENSE

(Gain + offset)

Accuracy Total output error

V

SENSE

= -100mV -5 5 %

(Gain + offset)

BW Bandwidth V

CMRR V

SENSE+

common

SENSE(DC)

V

SENSE(AC)

VIN = 2.7 to 20V TBD 60 dB

= 100mV
= 63mV

300 kHz

PP

mode rejection ratio

Flag TP Flag trip point Referred to V

V

FL

Flag low output

I

= 100␮A60200mV

SINK

SENSE

-2.5 +2.5 mV

voltage

I

FH

Flag high leakage

VOH = 5V 1 ␮A

current

NOTES:

(a) - V
(b) Temperature dependent measurements are extracted from characterisation and simulation results.

SENSE

= "V

SENSE+

" - "V

SENSE-

"

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