Diodes ZXCT1012 User Manual

R

REDUCED HEIGHT MICRO-POWER CURRENT MONITOR

Description

The ZXCT1012 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 ZXCT1012 takes the voltage developed across a small
value resistor and translates it into a proportional output
current. A user defined output resistor scales the output
current into a ground referenced voltage.

The ZXCT1012 has the accuracy specification of the
ZXCT1010 but in TSOT25.

A minimum operating current of just 3.5μA, combined with its
TSOT25 package make it suitable for portable battery
equipment where size and current consumption are critical.

The wide input voltage range down to as low as 2.5V make it
suitable for a wide range of applications requiring direct
operation from a battery.

Pin Assignments

(Top View)
1

NC

GND

2

OUT

TSOT25

ZXCT1012

SENSE-

5

43

SENSE+

Features

• 2.5V to 20V supply range

• 3.5μA quiescent current

• Current output - user set gain

• Thin package - TSOT25

• Temperature range -40 to 85°C

Typical Application Circuit

V

Applications

• Battery fuel gauge

• Battery chargers

• Overcurrent monitor

• Power management

IN

SENSE

SENSE+ SENSE-

ZXCT1012

GND

OUT

R

LOAD

V

OUT

R

OUT

ZXCT1012

Document number: DS33444 Rev. 2 - 2

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ZXCT1012

Pin Descriptions

Pin Name Description

1 N/C
2 GND

3 OUT

4 SENSE+

5 SENSE-

Absolute Maximum Ratings (T

V
Voltage on any pin(relative to GND pin) -0.6 and V
V
Ambient Operating Temperature Range -40 to 85 °C
Storage Temperature -55 to 150 °C
Maximum Junction Temperature 150 °C

Power Dissipation (TA = 25°C)

Max. 20 V

SENSE+

(Note 1) -0.15 to 3 V

SENSE

Package

(Note 2)

TSOT25 250°C/W 500mW

Recommended Operating Conditions

Symbol Parameter Min. Max. Units

VIN Sense+ range 2.5 20 V

TA Ambient temperature range differential -40 85 C

V

Sense voltage 10 2500 mV

SENSE

V

Output voltage swing 0 V

OUT

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

Notes: 1. V

2. Mounted on 30mm x 16mm x1.1mm FR4 board with 1oz copper.

is defined as the differential voltage between the SENSE+ and SENSE- pins. (V

SENSE

ZXCT1012

Document number: DS33444 Rev. 2 - 2

No connection
Ground connection
Output current pin. Current generated due to a difference voltage

between V
value resistor connected to ground creates an output voltage. The
maximum voltage out of this pin will be V
This pin should be connected to the rail whose current is being
measured and also provides power to internal circuitry. It is the
positive input of the current monitor and has an input range from
20V down to 2.5V. The current through this pin varies with
differential sense voltage.
This is the negative input of the current monitor and has an input
range from 20V down to 2.5V.

Description Rating Unit

R

P

θJA

REDUCED HEIGHT MICRO-POWER CURRENT MONITOR

SENSE+

and V

= 25°C)

A

@ 25°C

DISS

flows out of this pin. A suitable

SENSE-

SENSE-

300

(De-rate to 0 at 150°C)

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- 1.5V.

+0.5 V

SENSE+

mW

-15 V

SENSE-

SENSE

= V

SENSE+

- V

SENSE-

)

September 2011

© Diodes Incorporated

ZXCT1012

Electrical Characteristics (T

Symbol Parameter Conditions

I

Output Current

OUT

IQ Ground Pin Current V

I

SENSE- Pin Input Current 100 nA

SENSE-

ACC Accuracy
Gm

TC Temperature Coefficient

BW Bandwidth

CMRR

(Note 4)

Notes: 3. Temperature dependent measurements are extracted from characterisation and simulation results.

4. With the ZXCT1012 using SENSE+ as its power supply pin, common mode rejection cannot be distinguished from power supply rejection.

Transconductance,I
(Note 3)

Common Mode Rejection Ratio

ZXCT1012

Document number: DS33444 Rev. 2 - 2

OUT/VSENSE

REDUCED HEIGHT MICRO-POWER CURRENT MONITOR

= 25°C, VIN = V

A

V

SENSE

V

SENSE

V

SENSE

V

SENSE

V

SENSE
SENSE

R

SENSE

V

SENSE

V

SENSE

TA = 0 to 50°C (Note 3)

= 5pF

C

L

R

OUT

V

SENSE

VIN = 2.5V to 20V

SENSE+

= 0V
= 10mV
= 40mV
= 100mV
= 200mV
= 0V 3.5 8 µA

= 0.1V
= 200mV

= 200mV

= 1kΩ

= 100mV, R

= 5V; unless otherwise specified)

Limits

Min. Typ. Max.

V

SENSE

V

SENSE

= 10mV
= 100mV
= 1kΩ

OUT

0

85

380

0.975

1.95

-2.5 2.5 %
10 mA/V

500 ppm/°C

80 dB

0.3
100
400

1.00

2.00

300

2

15
115
420

1.025

2.05

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© Diodes Incorporated

Unit

µA
µA

µA
mA
mA

kHz

MHz