Diodes ZXCT1050 User Manual

ZXCT1050

SENSE-

SENSE+

V

CC

GND

OUT

1

2

3

5

4

Precision wide input range current monitor

Description

The ZXCT1050 is a wide input range current monitor, which operates over a range of input voltages from ground up to V

-2V. As a

CC

result the ZXCT1050 can be used on the high or low side of the load.

The ZXCT1050 provides variable gain by using two external resistors. The first of which sets the transconductance and the second setting the overall gain.

The very low offset voltage enables a typical accuracy of 1% for sense voltages of only 30mV, giving better tolerances for small sense resistors necessary at higher currents.

Features

• Accurate down to end current sensing

• Output voltage scaling x10

•0 to V

• 2.7 to 20V supply range

• 50µA quiescent current

• SOT23-5 package

-2V sense input range

CC

Applications

• Power supply

• DC motor and solenoid control

• Battery management

• Over current monitor

• Power management

• Short circuit detection

Pin connections Typical application circuit

R

IN

V

CC

SENSE

R

SHUNT

SENSE+ SENSE-

ZXCT1050

OUT

R

GAIN

Load

Ordering information

Order code Pack Part mark Reel size

(inches)

ZXCT1050E5TA SOT23-5 1050 7 8 3000

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Tape width

(mm)

Quantity

per reel

Absolute maximum ratings

VCC max. 20V

ZXCT1050

Voltage on SENSE- and SENSE+ -0.6 to V

Voltage on all other pins -0.6V and V

V

SENSE

= ‘(V

SENSE

+) - (V

-)’ 500mV

SENSE

CC

+0.6V

Operating temperature -40 to 125°C

Storage temperature -55 to 150°C

Maximum junction temperature 150°C

Package power dissipation 300mW

*

at TA = 25°C (De-rate to zero for TJ = 150°C)

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

Recommended operating conditions

Parameter Min. Max. Units

V

SENSE+

V

CC

V

SENSE

V

OUT

T

A

Common-mode sense input range 0 VCC-2

V

Supply voltage range 2.7 20 V

Differential sense input voltage range 10 300 mV

Output voltage range 0 VCC-2 V

Ambient temperature range -40 125 °C

Recommended resistor gain setting combinations

Gain R

SH

R

G

10 7.5k⍀ 3.75k⍀ 20 7.5k⍀ 7.5k⍀ 50 7.5k⍀ 18.7k⍀

100 7.5k⍀ 37.5k⍀

20 3.75k⍀ 3.75k⍀ 50 1.5k⍀ 3.75k⍀

100 750⍀ 3.75k⍀

Pin function table

PIN Name Description

1V

CC

2 GND Ground pin. 3 OUT Output pin. A resistor, R

4 SENSE+ This is the positive input of the current monitor and has an input range from

5 SENSE- This is the negative input of the current monitor and has an input range from

This is the analog supply and provides power to internal circuitry.

, connected from this pin pin down to ground

GAIN

develops an output voltage.

0V up to VCC – 2V.

0V up to V voltage. A resistor, R

– 2V. The current through this pin varies with differential sense

CC

, from this pin to the rail being sensed set the

SHUNT

transconductance of the current monitor.

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Electrical characteristics

NOTES:

ZXCT1050

Test conditions TA = 25°C, V

= 10V, VCC = 12V, V

SENSE+

= 100mV, RSH = 7.5k⍀, RG = 3.75k⍀.

SENSE

Symbol Parameter Conditions Min. Typ. Max. Units

I

Q

V

OUT

I

SENSE+

I

SENSE-

V

OUT

TC V

VCC pin current V

Output voltage V

V

SENSE+

V

SENSE-

OUT

input current V

variation with

= 0V 45 70 µA

SENSE

= 0V

SENSE

=30mV =100mV =150mV

= 0V 60 150 nA

SENSE

= 0V 15 150 nA

SENSE

See note

(*)

0

285

0.97

1.45

3

300

1.00

1.50

mV

15

315

1.03

1.55

mV V V

300 ppm/°C

temperature

Gain V

OUT/VSENSE

10

Accuracy Total output error -3 3 %

BW Bandwidth V

SENSE(DC)

= 10mV

V

SENSE(DC)

V

SENSE(AC)

= 10mV CL = 5pF,

PP

300 kHz

0.8 MHz

= 100mV

PSRR Power supply

rejection ratio

CMRR Common mode

rejection ratio

(*) Temperature dependent measurements are extracted from characterisation and simulation results.

V

= 2.7V to 20V

CC

V

SENSE+

V

CC

V

SENSE+

= 0.7V

= 20V

= 0 to 18V

60 dB

70 dB

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