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ISO1541

Bidirectional I²C Isolator

The ISO1541 is a bidirectional i²c isolator from Texas Instruments. View the full ISO1541 datasheet below including electrical characteristics, absolute maximum ratings.

Manufacturer

Texas Instruments

Overview

Part: ISO1540, ISO1541 — Texas Instruments

Type: Low-Power Bidirectional I2C Isolators

Description: Low-power, bidirectional isolators compatible with I2C interfaces, supporting up to 1 MHz operation, 3-V to 5.5-V supply range, and 4000-VPK isolation.

Operating Conditions:

  • Supply voltage: 3–5.5 V
  • Operating temperature: -40 to 125 °C
  • Max operating frequency: 1 MHz
  • Max capacitive load: 40 pF (Side 1), 400 pF (Side 2)

Absolute Maximum Ratings:

  • Max supply voltage: 6 V (VCC1, VCC2)
  • Max continuous current: ±20 mA (SDA1, SCL1), ±100 mA (SDA2, SCL2)
  • Max junction temperature: 150 °C
  • Storage temperature range: -65 to 150 °C

Key Specs:

  • Side 1 Output Current (IOL1): 0.5 mA to 3.5 mA
  • Side 2 Output Current (IOL2): 0.5 mA to 35 mA
  • Isolation Voltage: 4000 VPK (DIN EN 60747-5-2), 2500 VRMS (UL 1577)
  • Common-Mode Transient Immunity (CMTI): 25 kV/μs (min), 50 kV/μs (typ)
  • Supply Current, Side 1 (ISO1540, 3-3.6V): 2.4 mA (typ)
  • Supply Current, Side 2 (ISO1540/1541, 3-3.6V): 1.7 mA (typ)
  • Low-Level Output Voltage, Side 1 (VOL1): 650 mV (min) to 800 mV (max) for 0.5 mA ≤ I ≤ 3.5 mA
  • Low-Level Output Voltage, Side 2 (VOL2): 400 mV (max) for 0.5 mA ≤ I ≤ 35 mA

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
  • 4000-VPK Isolation per DIN EN 60747-5-2 (VDE 0884 Part 2)
  • 2500-VRMS Isolation for 1 minute per UL 1577

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

  • 2 · Isolated Bidirectional, I 2 C Compatible, Communications

Applications

  • Isolated I 2 C Bus
  • SMBus and PMBus Interfaces
  • Open-drain Networks
  • Motor Control Systems
  • Battery Management
  • I 2 C Level Shifting

Pin Configuration

ISO1540 and ISO1541I / ODESCRIPTIONDESCRIPTIONDESCRIPTIONDESCRIPTION
NAMEPINISO1540ISO1541ISO1540ISO1541
VCC11--Supply Voltage, Side 1Supply Voltage, Side 1
SDA12I / OI / OSerial Data, Side 1 Input/OutputSerial Data, Side 1 Input/Output
SCL13I / OISerial Clock Input/Output, Side 1Serial Clock Input, Side 1
GND14--Ground, Side 1Ground, Side 1
GND25--Ground, Side 2Ground, Side 2
SCL26I / OOSerial Clock Input/Output, Side 2Serial Clock Output, Side 2
SDA27I / OI / OSerial Data Input/Output, Side 2Serial Data Input/Output, Side 2
VCC28--Supply Voltage, Side 2Supply Voltage, Side 2

Electrical Characteristics

Over recommended operating conditions, unless otherwise noted

PARAMETERPARAMETERPARAMETERTEST CONDITIONSTEST CONDITIONSMINTYPMAXUNIT
SUPPLY CURRENT (3V ≤ VCC1, VCC2 ≤ 3.6V)SUPPLY CURRENT (3V ≤ VCC1, VCC2 ≤ 3.6V)SUPPLY CURRENT (3V ≤ VCC1, VCC2 ≤ 3.6V)SUPPLY CURRENT (3V ≤ VCC1, VCC2 ≤ 3.6V)SUPPLY CURRENT (3V ≤ VCC1, VCC2 ≤ 3.6V)SUPPLY CURRENT (3V ≤ VCC1, VCC2 ≤ 3.6V)SUPPLY CURRENT (3V ≤ VCC1, VCC2 ≤ 3.6V)SUPPLY CURRENT (3V ≤ VCC1, VCC2 ≤ 3.6V)SUPPLY CURRENT (3V ≤ VCC1, VCC2 ≤ 3.6V)
I CC1Supply Current, Side 1ISO1540 ISO1541V SDA1 , V SCL1 = GND1; V SDA2 , V SCL2 = GND2See Figure 1; R 1 ,R 2 = Open, C 1 ,C 2 = Open2.4 2.13.6 3.3mA
I CC2Supply Current, Side 2ISO1540 and ISO1541V SDA1 , V SCL1 = GND1; V SDA2 , V SCL2 = GND2See Figure 1; R 1 ,R 2 = Open, C 1 ,C 2 = Open1.72.7mA
IISO1540V SDA1 , V SCL1 = VCC1; V SDA2 ,See Figure 1; R 1 ,R 2 = Open, C 1 ,C 2 = Open2.53.8mA
CC1Supply Current, Side 1ISO1541V SDA1 , V SCL1 = VCC1; V SDA2 ,See Figure 1; R 1 ,R 2 = Open, C 1 ,C 2 = Open2.33.6mA
I CC2Supply Current, Side 2ISO1540 and ISO1541V SDA1 , V SCL1 = VCC1; V SDA2 ,See Figure 1; R 1 ,R 2 = Open, C 1 ,C 2 = Open1.93.1mA
SUPPLY CURRENT (4.5 V ≤ VCC1, VCC2 ≤ 5.5 V)SUPPLY CURRENT (4.5 V ≤ VCC1, VCC2 ≤ 5.5 V)SUPPLY CURRENT (4.5 V ≤ VCC1, VCC2 ≤ 5.5 V)SUPPLY CURRENT (4.5 V ≤ VCC1, VCC2 ≤ 5.5 V)SUPPLY CURRENT (4.5 V ≤ VCC1, VCC2 ≤ 5.5 V)SUPPLY CURRENT (4.5 V ≤ VCC1, VCC2 ≤ 5.5 V)SUPPLY CURRENT (4.5 V ≤ VCC1, VCC2 ≤ 5.5 V)SUPPLY CURRENT (4.5 V ≤ VCC1, VCC2 ≤ 5.5 V)SUPPLY CURRENT (4.5 V ≤ VCC1, VCC2 ≤ 5.5 V)
I CC1Supply Current, Side 1ISO1540V SCL1 = GND1; V SDA2 , V SCL2 = GND2See Figure 1; R 1 ,R 2 = Open, C 1 ,C 2 = Open3.14.7mA
I CC1Supply Current, Side 1ISO1541V SCL1 = GND1; V SDA2 , V SCL2 = GND2See Figure 1; R 1 ,R 2 = Open, C 1 ,C 2 = Open2.84.4mA
I CC2Supply Current, Side 2ISO1540 and ISO1541V SCL1 = GND1; V SDA2 , V SCL2 = GND2See Figure 1; R 1 ,R 2 = Open, C 1 ,C 2 = Open2.33.7mA
I CC1Supply Current, Side 1ISO1540 ISO1541V SDA1 , V SCL1 = VCC1; V SDA2 ,See Figure 1; R 1 ,R 2 = Open, C 1 ,C 2 = Open3.1 2.94.7 4.5mA
I CC2Supply Current, Side 2ISO1540 and ISO1541V SDA1 , V SCL1 = VCC1; V SDA2 ,See Figure 1; R 1 ,R 2 = Open, C 1 ,C 2 = Open2.54mA
PARAMETERPARAMETERPARAMETERPARAMETERTEST CONDITIONSMINTYPMAXUNIT
SIDE 1 (Only)SIDE 1 (Only)SIDE 1 (Only)SIDE 1 (Only)SIDE 1 (Only)SIDE 1 (Only)SIDE 1 (Only)SIDE 1 (Only)SIDE 1 (Only)
V ILT1Voltage Input Threshold 'Low', Side 1 (SDA1, SCL1)Voltage Input Threshold 'Low', Side 1 (SDA1, SCL1)Voltage Input Threshold 'Low', Side 1 (SDA1, SCL1)Voltage Input Threshold 'Low', Side 1 (SDA1, SCL1)500550660mV
V IHT1Voltage Input Threshold 'High', Side 1 (SDA1, SCL1)Voltage Input Threshold 'High', Side 1 (SDA1, SCL1)Voltage Input Threshold 'High', Side 1 (SDA1, SCL1)Voltage Input Threshold 'High', Side 1 (SDA1, SCL1)540610700mV
V HYST1Voltage Input Hysteresis, Side 1 V IHT1 - V ILT1Voltage Input Hysteresis, Side 1 V IHT1 - V ILT1Voltage Input Hysteresis, Side 1 V IHT1 - V ILT1Voltage Input Hysteresis, Side 1 V IHT1 - V ILT14060mV
V OL1 (1)Low-Level Output Voltage, Side 1 (SDA1,SCL1) 0.5 mA ≤ (I SDA1 andLow-Level Output Voltage, Side 1 (SDA1,SCL1) 0.5 mA ≤ (I SDA1 andLow-Level Output Voltage, Side 1 (SDA1,SCL1) 0.5 mA ≤ (I SDA1 andLow-Level Output Voltage, Side 1 (SDA1,SCL1) 0.5 mA ≤ (I SDA1 and650800mV
Δ V OIT1 (1)(2)Low-Level Output Voltage to High-Level Input Voltage I SCL1 ) ≤ 3.5 mA Threshold Difference, Side 1 (SDA1, SCL1)Low-Level Output Voltage to High-Level Input Voltage I SCL1 ) ≤ 3.5 mA Threshold Difference, Side 1 (SDA1, SCL1)Low-Level Output Voltage to High-Level Input Voltage I SCL1 ) ≤ 3.5 mA Threshold Difference, Side 1 (SDA1, SCL1)Low-Level Output Voltage to High-Level Input Voltage I SCL1 ) ≤ 3.5 mA Threshold Difference, Side 1 (SDA1, SCL1)50mV
SIDE 2 (Only)SIDE 2 (Only)SIDE 2 (Only)SIDE 2 (Only)SIDE 2 (Only)SIDE 2 (Only)SIDE 2 (Only)SIDE 2 (Only)SIDE 2 (Only)
V ILT2Voltage Input Threshold 'Low', Side 2 (SDA2, SCL2)Voltage Input Threshold 'Low', Side 2 (SDA2, SCL2)Voltage Input Threshold 'Low', Side 2 (SDA2, SCL2)Voltage Input Threshold 'Low', Side 2 (SDA2, SCL2)0.3 x VCC20.4 x VCC2mV
V IHT2Voltage Input Threshold 'High', Side 2 (SDA2, SCL2)Voltage Input Threshold 'High', Side 2 (SDA2, SCL2)Voltage Input Threshold 'High', Side 2 (SDA2, SCL2)Voltage Input Threshold 'High', Side 2 (SDA2, SCL2)0.4 x VCC20.5 x VCC2mV
V HYST2Voltage Input Hysteresis, Side 2 V IHT2 - V ILT2Voltage Input Hysteresis, Side 2 V IHT2 - V ILT2Voltage Input Hysteresis, Side 2 V IHT2 - V ILT2Voltage Input Hysteresis, Side 2 V IHT2 - V ILT20.05 x VCC2mV
V OL2Low-Level Output Voltage, 0.5 mA ≤ (I SDA2 and Side 2 (SDA2, SCL2) I SCL2 ) ≤ 35 mALow-Level Output Voltage, 0.5 mA ≤ (I SDA2 and Side 2 (SDA2, SCL2) I SCL2 ) ≤ 35 mALow-Level Output Voltage, 0.5 mA ≤ (I SDA2 and Side 2 (SDA2, SCL2) I SCL2 ) ≤ 35 mALow-Level Output Voltage, 0.5 mA ≤ (I SDA2 and Side 2 (SDA2, SCL2) I SCL2 ) ≤ 35 mA400mV
BOTH SIDESBOTH SIDESBOTH SIDESBOTH SIDESBOTH SIDESBOTH SIDESBOTH SIDESBOTH SIDESBOTH SIDES
\I I \Input Leakage Currents (SDA1, SCL1, SDA2, SCL2)Input Leakage Currents (SDA1, SCL1, SDA2, SCL2)Input Leakage Currents (SDA1, SCL1, SDA2, SCL2)V SDA1 , V SCL1 = VCC1; V SDA2 , V SCL2 = VCC20.01
C IInput Capacitance to Local Ground (SDA1, SCL1, SDA2, SCL2)Input Capacitance to Local Ground (SDA1, SCL1, SDA2, SCL2)Input Capacitance to Local Ground (SDA1, SCL1, SDA2, SCL2)V I = 0.4 x sin(2E6 π t) + 2.5 V7pF
CMTICommon-Mode Transient ImmunityCommon-Mode Transient ImmunityCommon-Mode Transient ImmunitySee Figure 32550kV/μs
V CCUV (3)V CC Undervoltage Lockout Threshold (Side 1 and Side 2)V CC Undervoltage Lockout Threshold (Side 1 and Side 2)V CC Undervoltage Lockout Threshold (Side 1 and Side 2)2.12.52.8V

Absolute Maximum Ratings

VALUESVALUESUNIT
MINMAX
VCC1, VCC2VCC1, VCC2VCC1, VCC2-0.56V
Supply voltageSDA1, SCL1SDA1, SCL1SDA1, SCL1-0.5VCC1 + 0.5V
SDA2, SCL2SDA2, SCL2SDA2, SCL2-0.5VCC2 + 0.5V
Output currentSDA1, SCL1SDA1, SCL1SDA1, SCL1±20mA
SDA2, SCL2SDA2, SCL2SDA2, SCL2±100mA
ElectrostaticHuman Body ModelESDA, JEDEC JS-001-2012Bus Pins±8kV
ElectrostaticESDA, JEDEC JS-001-2012All Pins±4kV
DischargeField-Induced-Charged Device ModelJEDEC JESD22-C101EAll Pins±1.5kV
DischargeMachine ModelJEDEC JESD22-A115-AAll Pins±200V
T J(MAX)Maximum junction temperatureMaximum junction temperatureMaximum junction temperature150°C
T STGStorage temperature rangeStorage temperature rangeStorage temperature range-65150°C

Recommended Operating Conditions

MINNOMMAXUNIT
VCC1, VCC2Supply Voltage35.5V
V SDA1 , V SCL1Input/Output Signal Voltages, Side 10VCC1V
V SDA2 , V SCL2Input/Output Signal Voltages, Side 20VCC2V
V IL1Low-Level Input Voltage, Side 100.5V
V IH1High-Level Input Voltage, Side 10.7 x VCC1VCC1V
V IL2Low-Level Input Voltage, Side 200.3 x VCC2V
V IH2High-Level Input Voltage, Side 20.7 x VCC2VCC2V
I OL1Output Current, Side 10.53.5mA
I OL2Output Current, Side 20.535mA
C b1Maximum Capacitive Load, Side 140pF
C b2Maximum Capacitive Load, Side 2400pF
f MAXMaximum Operating Frequency (1)1MHz
T AAmbient Temperature-40125°C
T JJunction Temperature-40136°C
T SDThermal Shutdown139171°C

Thermal Information

THERMAL METRIC (1)THERMAL METRIC (1)ISO1540 ISO1541UNITS
D (8 PINS)
θ JAJunction-to-ambient thermal resistance114.6°C/W
θ JCtopJunction-to-case (top) thermal resistance69.6°C/W
θ JBJunction-to-board thermal resistance55.3°C/W
ψ JTJunction-to-top characterization parameter27.2°C/W
ψ JBJunction-to-board characterization parameter54.7°C/W
θ JCbotJunction-to-case (bottom) thermal resistancen/a°C/W

Typical Application

Related Variants

The following components are covered by the same datasheet.

Part NumberManufacturerPackage
ISO1540Texas Instruments
ISO1540DTexas Instruments
ISO1540DRTexas Instruments
ISO154XTexas Instruments
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