ISO154X

Low-Power Bidirectional I<sup>2</sup>C Isolators

Manufacturer

Texas Instruments

Overview

Part: ISO1540, ISO1541 from Texas Instruments

Type: Low-Power Bidirectional I²C Isolator

Key Specs:

Operation Speed: Up to 1 MHz
Supply Voltage Range: 3 V to 5.5 V
Operating Temperature Range: -40°C to 125°C
Transient Immunity: ±50 kV/μs (Typical)
Isolation Voltage (Peak): 4000 Vpk
Isolation Voltage (RMS): 2500 Vrms
Side 1 Sink Current: 3.5 mA
Side 2 Sink Current: 35 mA
HBM ESD Protection (Bus Pins): 8 kV
HBM ESD Protection (All Pins): 4 kV

Features:

Isolated Bidirectional, I²C Compatible, Communications
Supports up to 1 MHz Operation
3-V to 5.5-V Supply Range
Open Drain Outputs with 3.5-mA Side 1 and 35-mA Side 2 Sink Current Capability
-40°C to 125°C Operating Temperature
±50 kV/μs Transient Immunity (Typical)
HBM ESD Protection of 4 kV on All Pins: 8 kV on Bus Pins

Applications:

Isolated I²C Bus
SMBus and PMBus Interfaces
Open-drain Networks
Motor Control Systems
Battery Management
I²C Level Shifting

Package:

D-8: 8 pins

Features

Isolated Bidirectional, I²C Compatible, Communications
Supports up to 1 MHz Operation
3-V to 5.5-V Supply Range
Open Drain Outputs with 3.5-mA Side 1 and 35-mA Side 2 Sink Current Capability
-40°C to 125°C Operating Temperature
±50 kV/μs Transient Immunity (Typical)
HBM ESD Protection of 4 kV on All Pins: 8 kV on Bus Pins

APPLICATIONS

Isolated I²C Bus
SMBus and PMBus Interfaces
Open-drain Networks
Motor Control Systems
Battery Management
I²C Level Shifting

Applications

Isolated I²C Bus
SMBus and PMBus Interfaces
Open-drain Networks
Motor Control Systems
Battery Management
I²C Level Shifting

Pin Configuration

ISO1540 and ISO1541	1/0			DESCRIPTION
NAME	PIN	ISO1540	ISO1541	ISO1540
VCC1	1	-	-	Supply Voltage, Side 1
SDA1	2	1/0	1/0	Serial Data, Side 1 Input/Output
SCL1	3	1/0	1	Serial Clock Input/Output, Side 1
GND1	4	-	-	Ground, Side 1
GND2	5	-	-	Ground, Side 2
SCL2	6	1/0	0	Serial Clock Input/Output, Side 2
SDA2	7	1/0	1/0	Serial Data Input/Output, Side 2
VCC2	8	-	-	Supply Voltage, Side 2

Electrical Characteristics

Over recommended operating conditions, unless otherwise noted

	PARAMETER		TEST	CONDITIONS	MIN	TYP	MAX	UNIT
SUPPLY CI	JRRENT (3V ≤ VCC1, VCC	2 < 3.6V)	1	-
0011 21 00	MREIT (37 2 7001, 700)	ISO1540				2.4	3.6
I _CC1	Supply Current, Side 1	ISO1541	V_SDA1 , V_SCL1 = GND1 ;			2.1	3.3
		ISO1540 and	V_SDA2 ,
I _CC2	Supply Current, Side 2	ISO1540 and	V_SCL2 = GND2	See Figure 1;		1.7	2.7
	0 10 1011	ISO1540	V _SDA1 ,	R₁,R₂ = Open, C₁,C₂ = Open		2.5	3.8	mA
I _CC1	Supply Current, Side 1	ISO1541	V_SCL1 = VCC1;	17.2		2.3	3.6
I _CC2	Supply Current, Side 2	ISO1540 and ISO1541	V_SDA2 , V_SCL2 = VCC2			1.9	3.1
SUPPLY CL	JRRENT (4.5 V ≤ VCC1, VC	CC2 ≤ 5.5 V)
	•	ISO1540	V			3.1	4.7
I _CC1	Supply Current, Side 1	ISO1541	V_SDA1 , V_SCL1 = GND1 ;			2.8	4.4
I _CC2	Supply Current, Side 2	ISO1540 and ISO1541	V_SDA2 , V_SCL2 = GND2	See Figure 1;		2.3	3.7
		ISO1540		R₁,R₂ = Open, C₁,C₂ = Open		3.1	4.7	mA
I _CC1	Supply Current, Side 1	ISO1541	V_SDA1 , V_SCL1 = VCC1 ;	0 ₁ ,0 ₂ = Open		2.9	4.5
I _CC2	Supply Current, Side 2	ISO1540 and ISO1541	V_SDA2 , V_SCL2 = VCC2			2.5	4
	PARAM			TEST CONDITIONS	MIN	TYP	MAX	UNIT
SIDE 1 (Onl
V _ILT1	Voltage Input Threshold Side 1 (SDA1, SCL1)	"Low",			500	550	660
V _IHT1	Voltage Input Threshold Side 1 (SDA1, SCL1)	"High",			540	610	700
V _HYST1	Voltage Input Hysteresis Side 1 V _IHT1 - V _ILT1	5,			40	60		mV
V _OL1 ⁽¹⁾	Low-Level Output Voltag Side 1 (SDA1,SCL1)	ge,		0.5. 4.4	650		800
ΔV _OIT1 ⁽¹⁾⁽²⁾	Low-Level Output Voltaç Threshold Difference, Side 1 (SDA1, SCL1)	ge to High-Level I	nput Voltage	0.5 mA ≤ ( I_SDA1 and I_SCL1 ) ≤ 3.5 mA	50
SIDE 2 (Onl	y)			•			•
V _ILT2	Voltage Input Threshold Side 2 (SDA2, SCL2)	"Low",			0.3 x VCC2		0.4 x VCC2
V _IHT2	Voltage Input Threshold Side 2 (SDA2, SCL2)	"High",			0.4 x VCC2		0.5 x VCC2	.,
V _HYST2	Voltage Input Hysteresis Side 2 V _IHT2 - V _ILT2	5,			0.05 x VCC2			mV
V _OL2	Low-Level Output Voltag Side 2 (SDA2, SCL2)	ge,		0.5 mA ≤ (I_SDA2 and I_SCL2) ≤ 35 mA			400
BOTH SIDE
1 ₁	Input Leakage Currents (SDA1, SCL1, SDA2, SC	CL2)		V_SDA1 , V_SCL1 = VCC1 ; V_SDA2 , V_SCL2 = VCC2		0.01	10	μΑ
C _I	Input Capacitance to Loc (SDA1, SCL1, SDA2, SC	cal Ground CL2)		V₁ = 0.4 × sin(2E6π t) + 2.5 V		7		pF
CMTI	Common-Mode Transier			See Figure 3	25	50		kV/μs
V _CCUV ⁽³⁾	V _CC Undervoltage Locko (Side 1 and Side 2)	out Threshold			2.1	2.5	2.8	V

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⁽¹⁾ This parameter does not apply to the ISO1541 SCL1 line as it is uni-directional. (2) ΔV_OIT1 = V_OL1 - V_IHT1. This represents the minimum difference between a Low-Level Output Voltage and a High-Level Input Voltage Threshold to prevent a permanent latch condition that would otherwise exist with bi-directional communication.

Any V_CC voltages, on either side, less than the minimum will ensure device lockout. Both V_CC voltages above the maximum will prevent device lockout.

Absolute Maximum Ratings

					VALUES	UNIT
				MIN	MAX
	VCC1, VCC2			–0.5	6	V
Supply voltage	SDA1, SCL1		–0.5	VCC1 + 0.5	V
	SDA2, SCL2		–0.5	VCC2 + 0.5	V
Output current	SDA1, SCL1				±20	mA
	SDA2, SCL2				±100	mA
			Bus Pins		±8	kV
	Human Body Model	ESDA, JEDEC JS-001-2012 All Pins			±4
Electrostatic Discharge	Field-Induced-Charged Device Model	JEDEC JESD22-C101E All Pins			±1.5	kV
	Machine Model JEDEC JESD22-A115-A				±200	V
TJ(MAX)	Maximum junction temperature				150	°C
TSTG	Storage temperature range			–65	150	°C

⁽¹⁾ Stresses beyond those listed under ABSOLUTE MAXIMUM RATINGS cause permanent damage to the device. These are stress ratings only and functional operation of the device at these or any other conditions beyond those indicated under RECOMMENDED OPERATING CONDITIONS is not implied. Exposure to absolute-maximum-rated conditions for extended periods affects device reliability.

Recommended Operating Conditions

		MIN	NOM MAX	UNIT
VCC1, VCC2	Supply Voltage	3	5.5
VSDA1, VSCL1	Input/Output Signal Voltages, Side 1	0	VCC1
VSDA2, VSCL2	Input/Output Signal Voltages, Side 2	0	VCC2
VIL1	Low-Level Input Voltage, Side 1	0	0.5	V
VIH1	High-Level Input Voltage, Side 1	0.7 x VCC1	VCC1
VIL2	Low-Level Input Voltage, Side 2	0	0.3 x VCC2
VIH2	High-Level Input Voltage, Side 2	0.7 x VCC2	VCC2
IOL1	Output Current, Side 1	0.5	3.5
IOL2	Output Current, Side 2	0.5	35	mA
Cb1	Maximum Capacitive Load, Side 1		40
Cb2	Maximum Capacitive Load, Side 2		400	pF
fMAX	Maximum Operating Frequency (1)		1	MHz
TA	Ambient Temperature	–40	125	°C
TJ	Junction Temperature	–40	136	°C
TSD	Thermal Shutdown	139	171	°C

⁽¹⁾ This represents the maximum frequency with the maximum bus load (Cb) and the maximum current sink (IO). If the system has less bus capacitance, then higher frequencies can be achieved.

Product Folder Links: ISO1540 ISO1541

⁽²⁾ All voltage values here within are with respect to the local ground terminal (GND1 or GND2) and are peak voltage values.

ELECTRICAL CHARACTERISTICS

Over recommended operating conditions, unless otherwise noted

	PARAMETER		TEST	CONDITIONS	MIN	TYP	MAX	UNIT
SUPPLY CI	JRRENT (3V ≤ VCC1, VCC	2 < 3.6V)	1	-
0011 21 00	MREIT (37 2 7001, 700)	ISO1540				2.4	3.6
I _CC1	Supply Current, Side 1	ISO1541	V_SDA1 , V_SCL1 = GND1 ;			2.1	3.3
		ISO1540 and	V_SDA2 ,
I _CC2	Supply Current, Side 2	ISO1540 and	V_SCL2 = GND2	See Figure 1;		1.7	2.7
	0 10 1011	ISO1540	V _SDA1 ,	R₁,R₂ = Open, C₁,C₂ = Open		2.5	3.8	mA
I _CC1	Supply Current, Side 1	ISO1541	V_SCL1 = VCC1;	17.2		2.3	3.6
I _CC2	Supply Current, Side 2	ISO1540 and ISO1541	V_SDA2 , V_SCL2 = VCC2			1.9	3.1
SUPPLY CL	JRRENT (4.5 V ≤ VCC1, VC	CC2 ≤ 5.5 V)
	•	ISO1540	V			3.1	4.7
I _CC1	Supply Current, Side 1	ISO1541	V_SDA1 , V_SCL1 = GND1 ;			2.8	4.4
I _CC2	Supply Current, Side 2	ISO1540 and ISO1541	V_SDA2 , V_SCL2 = GND2	See Figure 1;		2.3	3.7
		ISO1540		R₁,R₂ = Open, C₁,C₂ = Open		3.1	4.7	mA
I _CC1	Supply Current, Side 1	ISO1541	V_SDA1 , V_SCL1 = VCC1 ;	0 ₁ ,0 ₂ = Open		2.9	4.5
I _CC2	Supply Current, Side 2	ISO1540 and ISO1541	V_SDA2 , V_SCL2 = VCC2			2.5	4
	PARAM			TEST CONDITIONS	MIN	TYP	MAX	UNIT
SIDE 1 (Onl
V _ILT1	Voltage Input Threshold Side 1 (SDA1, SCL1)	"Low",			500	550	660
V _IHT1	Voltage Input Threshold Side 1 (SDA1, SCL1)	"High",			540	610	700
V _HYST1	Voltage Input Hysteresis Side 1 V _IHT1 - V _ILT1	5,			40	60		mV
V _OL1 ⁽¹⁾	Low-Level Output Voltag Side 1 (SDA1,SCL1)	ge,		0.5. 4.4	650		800
ΔV _OIT1 ⁽¹⁾⁽²⁾	Low-Level Output Voltaç Threshold Difference, Side 1 (SDA1, SCL1)	ge to High-Level I	nput Voltage	0.5 mA ≤ ( I_SDA1 and I_SCL1 ) ≤ 3.5 mA	50
SIDE 2 (Onl	y)			•			•
V _ILT2	Voltage Input Threshold Side 2 (SDA2, SCL2)	"Low",			0.3 x VCC2		0.4 x VCC2
V _IHT2	Voltage Input Threshold Side 2 (SDA2, SCL2)	"High",			0.4 x VCC2		0.5 x VCC2	.,
V _HYST2	Voltage Input Hysteresis Side 2 V _IHT2 - V _ILT2	5,			0.05 x VCC2			mV
V _OL2	Low-Level Output Voltag Side 2 (SDA2, SCL2)	ge,		0.5 mA ≤ (I_SDA2 and I_SCL2) ≤ 35 mA			400
BOTH SIDE
1 ₁	Input Leakage Currents (SDA1, SCL1, SDA2, SC	CL2)		V_SDA1 , V_SCL1 = VCC1 ; V_SDA2 , V_SCL2 = VCC2		0.01	10	μΑ
C _I	Input Capacitance to Loc (SDA1, SCL1, SDA2, SC	cal Ground CL2)		V₁ = 0.4 × sin(2E6π t) + 2.5 V		7		pF
CMTI	Common-Mode Transier			See Figure 3	25	50		kV/μs
V _CCUV ⁽³⁾	V _CC Undervoltage Locko (Side 1 and Side 2)	out Threshold			2.1	2.5	2.8	V

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Any V_CC voltages, on either side, less than the minimum will ensure device lockout. Both V_CC voltages above the maximum will prevent device lockout.

Thermal Information

	THERMAL METRIC(1)	ISO1540 ISO1541	UNITS
		D (8 PINS)
θJA	Junction-to-ambient thermal resistance	114.6
θJCtop	Junction-to-case (top) thermal resistance	69.6
θJB	Junction-to-board thermal resistance	55.3
ψJT	Junction-to-top characterization parameter	27.2	°C/W
ψJB	Junction-to-board characterization parameter	54.7
θJCbot	Junction-to-case (bottom) thermal resistance	n/a

Related Variants

The following components are covered by the same datasheet.

Part Number	Manufacturer	Package
ISO1540	unknown	—
ISO1540D	Texas Instruments	—
ISO1540DR	Texas Instruments
ISO1541	Texas Instruments	—

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