Diodes ZXCT1082, ZXCT1083, ZXCT1084, ZXCT1085, ZXCT1086 User Manual

A Product Line of

Diodes Incorporated

ZXCT1082/83/84/85/86/87

PRECISION HIGH VOLTAGE HIGH-SIDE CURRENT MONITORS

Description

The ZXCT1082 and ZXCT1083 are high side unipolar current sense monitors. These devices eliminate the need to disrupt the ground plane when sensing a load current.

The ZXCT1082/1084/1086 have 60V maximum operating voltage and ZXCT1083/1085/1087 have 40V maximum operating voltage.

The wide common-mode input voltage range and low quiescent currents coupled with SOT25 packages make them suitable for a range of applications; including automotive and systems operating from industrial 24-28V rails.

Their quiescent current is only 0.6µA thereby minimizing current sensing error.

The ZXCT1082 and ZXCT1083 use three external transconductance/gain setting resistors which increase versatility by permitting wide gain ranges and optimization of bandwidths.

The ZXCT1084/5/6/7 are fixed gain voltage output counterparts of the ZXCT1082/3.

Features

•Wide supply and common-mode voltage range

o	2.7V to 60V	ZXCT1082/84/86
o	2.7V to 40V	ZXCT1083/85/87

•Independent supply and input common-mode voltage

•Low quiescent current (0.6µA).

•AEC-Q100 Grade 1 qualified

•Extended industrial temperate range -40 to 125°C

•Package SOT25

Applications

•Automotive current measurement

•Industrial applications current measurement

•Battery management

•Over current monitor

•Power Management

•Current sources

Pin Assignments

OUT	1		5	VCC
GND
	2
S+
	3		4	S-

Typical Application Circuits

			RSENSE								VLOAD
VSUPPLY
						S-
		S+
		ZXCT1084/1085
VCC		ZXCT1086/1087									Load
	GND					OUT
ZXCT1084/85:				VOUT = 25 x VSENSE
ZXCT1086/87:				VOUT = 50 x VSENSE
VSUPPLY				RSENSE							VLOAD

RGT	R
S+	GT
	S-

VCC		ZXCT1082/1083				Load
	GND		OUT

RG

ZXCT1082/83: VOUT = VSENSE * RG

RGT

ZXCT1082/83/84/85/86/87	1 of 13	June 2011
Document number: DS32162 Rev. 2 - 2	www.diodes.com	© Diodes Incorporated

A Product Line of

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ZXCT1082/83/84/85/86/87

Pin Description

PIN

Name

Description

Common

ZXCT1082/3

ZXCT1084/5/6/7

1

OUT

Output pin.

Current output.

Voltage output

2

GND

Ground pin.

This is the positive input of the

An external resistor, RGT, should

Should be directly connected to

current monitor. It has a wide

3

S+

be connected from S+ to the input

common-mode input range. The

the input side (VSUPPLY) of the

current through this pin varies with

side (VSUPPLY) of the sense

sense resistor.

differential sense voltage.

resistor

This is the negative input of the

An external resistor, RGT, should

Should be directly connected to

4

S-

current monitor. It has a wide

be connected from S- to the load

the load side (VLOAD) of the sense

common-mode input range.

side (VLOAD) of the sense resistor.

resistor.

5

VCC

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

Absolute Maximum Ratings

Parameter

Rating

Unit

Voltage on S- and S+

ZXCT1082, ZXCT1084, ZXCT1086

-0.3 to 65

V

ZXCT1083, ZXCT1085, ZXCT1087

-0.3 to 45

Voltage on VCC

ZXCT1082, ZXCT1084, ZXCT1086

-0.3 to 65

V

ZXCT1083, ZXCT1085, ZXCT1087

-0.3 to 45

Voltage on OUT

-0.3 to VS-

V

Differential Input Voltage, VS+ - VS-

±800

mV

Input current into S+ or S- (†)

±12

mA

Storage Temperature

-55 to 150

°C

Maximum Junction Temperature

150

°C

Package Power Dissipation

300 at TA = 25°C

mW

(De-rate to zero at 150°C)

ESD Rating

Human Body Model

2

kV

Machine Model

200

V

Operation above the absolute maximum rating may cause device failure. Operation at the absolute maximum ratings, for

extended periods, may reduce device reliability.

(†) The differential input voltage limit, VS+ - VS- may be exceeded provided that the input current limit into S+ or S- is not exceeded

Recommended Operating Conditions

Symbol

Parameter

Min

Max

Units

VIN

ZXCT1083/1085/1087 Common-Mode Input Range

2.7

40

V

ZXCT1082/1084/1086 Common-Mode Input Range

2.7

60

VCC

ZXCT1083/1085/1087 Supply Voltage Range

2.7

40

V

ZXCT1082/1084/1086 Supply Voltage Range

2.7

60

VSENSE

Differential Sense Input Voltage Range

0

0.5

V

VOUT

Output Voltage Range

0

VS- -1

V

TA

Ambient Temperature Range

-40

125

°C

ZXCT1082/83/84/85/86/87

2 of 13

June 2011

Document number: DS32162 Rev. 2 - 2

www.diodes.com

© Diodes Incorporated

A Product Line of

Diodes Incorporated

ZXCT1082/83/84/85/86/87

Electrical Characteristics

Test Conditions TA = 25°C, VS+ = 12V, VCC = 5 V, VSENSE1 = 100mV, ZXCT1082/3 RGT = 5kΩ, RG = 125kΩ; unless otherwise stated. (FT = -40°C to +125°C)

Symbol	Parameter	Conditions		Min.	Typ.		Max.	Units
Input
IS+	S+ input current				1.7			µA
		VSENSE = 0mV (Note 1)	TA = FT			5
IS-	S- input current				1.7			µA
			TA = FT			5
		VSENSE = 0mV			±0.2	±1
VIO	Input Offset Voltage	ZXCT1082/3/4/5	TA = FT			±2.5		mV
	(Note 2)	ZXCT1086/87	TA = FT			±3
		Temperature co-efficient			±4			µV/K
Output
GT	Transconductance				200			µA/V
GT-ERR	Transconductance error	ZXCT1082/3		-1			+1	%
	(Note 4)	VSENSE = 10mV to 150mV	TA = FT	-2			+2
		(Note 1, 3)
GT-TC	Transconductance		TA = FT		10			nA/K
	temperature co-efficient
ZOUT	Output impedance	ZXCT1082/3			1¦¦5			GΩ¦¦pF
GV	Gain		1084/5		25			V/V
		ZXCT1084/5/6/7	1086/7		50
				-1			+1
GV-ERR	Gain error (Note 4)	VSENSE = 10mV to 150mV						%
			TA = FT	-2			+2
		(Note 1)
GV-TC	Voltage gain temperature		TA = FT		100			ppm/K
	co-efficient
ZOUT	Output impedance	ZXCT1084/5/6/7			125			kΩ
	Output relative to common	ZXCT1082/3		VLOAD - 1	VLOAD
VOUTH					- 0.8			V
	mode, VS-
		ZXCT1084/5/6/7		VS- - 1	VS- - 0.8

Notes: 1. For the ZXCT1082/83 VSENSE = “VSUPPLY” – “VLOAD“ where VLOAD is the load voltage or the lower potential side of the sense resistor. For the ZXCT1083/84/85/86 VSENSE = “VS+” – “VS-“

2.VIO is extrapolated from measurements for the gain-error test.

3.For VSENSE > 10mV, the internal voltage-current converter is fully linear. This enables a true offset to be defined and used.

4.Gain or transconductance error is calculated by applying two values of VSENSE and calculating the error of the slope vs. the ideal.

ZXCT1082/83/84/85/86/87	3 of 13	June 2011
Document number: DS32162 Rev. 2 - 2	www.diodes.com	© Diodes Incorporated

A Product Line of

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ZXCT1082/83/84/85/86/87

Electrical Characteristics (cont.)

Test Conditions TA = 25°C, VS+ = 12V, VCC = 5 V, VSENSE1 = 100mV, ZXCT1082/3 RGT = 5kΩ, RG = 125kΩ; unless otherwise stated. (FT = -40°C to +125°C)

Symbol	Parameter	Conditions		Min.	Typ.	Max.	Units
AC characteristics
BW	-3dB Small Signal	VSENSE (AC) = 10mVPP	G = 25		500		kHz
	Bandwidth	(Note 1)	G = 50		200
		VSENSE = 50mV to 300mV	G = 25		5
		step
ts(0.1%)	Settling time (0.1%)						µs
		VSENSE = 50mV to 200mV	G = 50		7
		step
	Output noise current	f = 1kHz			12		pA/√Hz
iN-OUT	density	f = 10kHz	ZXCT1082/3		10
	Total output noise	f = 0.1Hz to 100kHz			3		nARMS
	current
		f = 1kHz	ZXCT1084/5		1.5
	Output noise voltage		ZXCT1086/7		2.9		µV/√Hz
vN-OUT	density	f = 10kHz	ZXCT1084/5		1.2
			ZXCT1086/7		2.3
	Total output noise	f = 0.1Hz to 100kHz	ZXCT1084/5		390		µVRMS
	voltage		ZXCT1086/7		730
Power Supply
ICC	VCC Supply current	VSENSE = 0V			0.6		µA
			TA = FT			2
		ZXCT1083/5: VSENSE = 60mV;		80	100
		VCC = 2.7V to 40V	TA = FT	75
		ZXCT1087: VSENSE = 30mV;		80	100
PSRR	VCC Supply rejection	VCC = 2.7V to 40V	TA = FT	75			dB
(Note 5)	ratio	ZXCT1082/4: VSENSE = 60mV;		80	100
		VCC = 2.7V to 60V	TA = FT	75
		ZXCT1086: VSENSE = 30mV;		80	100
		VCC = 2.7V to 60V	TA = FT	75
		ZXCT1083/5: VSENSE = 60mV;		80	100
		VS+ = 2.7V to 40V	TA = FT	80
		ZXCT1087: VSENSE = 30mV;		80	100
CMRR	Common-mode sense	VS+ = 2.7V to 40V	TA = FT	80			dB
(Note 5)	rejection ratio	ZXCT1082/4: VSENSE = 60mV;		80	100
		VS+ = 2.7V to 60V	TA = FT	80
		ZXCT1086: VSENSE = 30mV;		80	100
		VS+ = 2.7V to 60V	TA = FT	80

Notes: 5. Measured relative to input

ZXCT1082/83/84/85/86/87	4 of 13	June 2011
Document number: DS32162 Rev. 2 - 2	www.diodes.com	© Diodes Incorporated