optoisolators

ISO1540

Every spec below is cited to the manufacturer datasheet. Pick your exact ordering code, compare the closest alternatives, then ask the assistant what it means for your design.

00 — Overview

What the ISO1540 family does

The ISO1540 and ISO1541 are low-power, bidirectional I2C isolators featuring 3-V to 5.5-V supply ranges, 1-MHz operation, 3.5-mA side 2 sink current, and 40°C to 125°C operating temperatures. These devices support up to 50-kV/µs transient immunity and 4-kV HBM ESD protection on all pins. The ISO1540 provides two isolated bidirectional channels for clock and data lines, while the ISO1541 offers a bidirectional data channel and a unidirectional clock channel. Engineers typically use these components in isolated I2C buses, SMBus and PMBus interfaces, open-drain networks, motor control systems, battery management units, and I2C level shifting applications to prevent noise currents from damaging sensitive circuitry.

Next step
Start building with ISO1540 → Every number above is cited straight from the datasheet — ask what they mean for your design, and the assistant answers from the same source documents.
Ordering code:
01 — Key specifications

ISO1540 datasheet parameters

ParameterMinTypMaxConditionsSource
quiescent current (abs max) — — 198 mA RθJA = 114.6°C/W, VI = 5.5 V, TJ = 150°C, TA = 25°C, seeFigure 6-1; is; 6.8 Safety Limiting Values TI datasheet, p. 9 — 6.8 Safety Limiting Values
output current 500 µA — 3.5 mA iol1; 6.3 Recommended Operating Conditions TI datasheet, p. 6 — 6.3 Recommended Operating Conditions
supply voltage range 3 V — 5.5 V vcc1; 6.3 Recommended Operating Conditions TI datasheet, p. 6 — 6.3 Recommended Operating Conditions
operating temperature -40 °C — 125 °C ta; 6.3 Recommended Operating Conditions TI datasheet, p. 6 — 6.3 Recommended Operating Conditions
power dissipation 105 mW — — VCC1 = VCC2 = 5.5 V, TJ = 150 °C, C1 = 20 pF, C2 = 400 pF; R1 = 1.4 kΩ, R2 = 94 Ω; Input a 1-MHz 50% duty cycle clock signal; pd; 6.5 Power Ratings TI datasheet, p. 7 — 6.5 Power Ratings
input capacitance — 7 pF — VI = 0.4 × sin(2E6πt) + 2.5 V; ci TI datasheet, p. 10 — over recommended operating conditions, unless otherwise noted
isolation voltage — — 566 V AC voltage (bipolar); viorm; DIN EN IEC 60747-17 (VDE 0884-17)(2) TI datasheet, p. 8 — 6.6 Insulation Specifications
propagation delay — 100 ns 165 ns See Figure 7-2; R1 = 953 Ω, C1 = 40 pFR2 = 95.3 Ω, C2 = 400 pF; 0.4 V to 0.3 × VCC1; tloop1; 3 V ≤ VCC1, VCC2 ≤ 3.6 V TI datasheet, p. 12 — 6.12 Switching Characteristics
operating frequency — — 1 MHz fmax; 6.3 Recommended Operating Conditions TI datasheet, p. 6 — 6.3 Recommended Operating Conditions
fall time 8 ns 17 ns 29 ns See Figure 7-1R1 = 953 Ω, C1 = 40 pF; 0.7 × VCC1 to 0.3 × VCC1; tf1(sda1, scl1); 3 V ≤ VCC1, VCC2 ≤ 3.6 V TI datasheet, p. 12 — 6.12 Switching Characteristics
output voltage low 570 mV — 800 mV 0.5 mA ≤ (ISDA1and ISCL1) ≤ 3.5 mA; vol1 TI datasheet, p. 10 — over recommended operating conditions, unless otherwise noted
cmti 25 GV/s 50 GV/s — SeeFigure 7-3; cmti TI datasheet, p. 10 — over recommended operating conditions, unless otherwise noted
channel count — 2 — Two isolated channels: clock and data lines (ISO1540 bidirectional, ISO1541 bidirectional data + unidirectional clock) TI datasheet, p. 1
01 — Key specifications

ISO1541 datasheet parameters

ParameterMinTypMaxConditionsSource
quiescent current (abs max) — — 198 mA RθJA = 114.6°C/W, VI = 5.5 V, TJ = 150°C, TA = 25°C, seeFigure 6-1; is; 6.8 Safety Limiting Values TI datasheet, p. 9 — 6.8 Safety Limiting Values
output current 500 µA — 3.5 mA iol1; 6.3 Recommended Operating Conditions TI datasheet, p. 6 — 6.3 Recommended Operating Conditions
supply voltage range 3 V — 5.5 V vcc1; 6.3 Recommended Operating Conditions TI datasheet, p. 6 — 6.3 Recommended Operating Conditions
operating temperature -40 °C — 125 °C ta; 6.3 Recommended Operating Conditions TI datasheet, p. 6 — 6.3 Recommended Operating Conditions
power dissipation 105 mW — — VCC1 = VCC2 = 5.5 V, TJ = 150 °C, C1 = 20 pF, C2 = 400 pF; R1 = 1.4 kΩ, R2 = 94 Ω; Input a 1-MHz 50% duty cycle clock signal; pd; 6.5 Power Ratings TI datasheet, p. 7 — 6.5 Power Ratings
input capacitance — 7 pF — VI = 0.4 × sin(2E6πt) + 2.5 V; ci TI datasheet, p. 10 — over recommended operating conditions, unless otherwise noted
isolation voltage — — 566 V AC voltage (bipolar); viorm; DIN EN IEC 60747-17 (VDE 0884-17)(2) TI datasheet, p. 8 — 6.6 Insulation Specifications
propagation delay — 100 ns 165 ns See Figure 7-2; R1 = 953 Ω, C1 = 40 pFR2 = 95.3 Ω, C2 = 400 pF; 0.4 V to 0.3 × VCC1; tloop1; 3 V ≤ VCC1, VCC2 ≤ 3.6 V TI datasheet, p. 12 — 6.12 Switching Characteristics
operating frequency — — 1 MHz fmax; 6.3 Recommended Operating Conditions TI datasheet, p. 6 — 6.3 Recommended Operating Conditions
fall time 8 ns 17 ns 29 ns See Figure 7-1R1 = 953 Ω, C1 = 40 pF; 0.7 × VCC1 to 0.3 × VCC1; tf1(sda1, scl1); 3 V ≤ VCC1, VCC2 ≤ 3.6 V TI datasheet, p. 12 — 6.12 Switching Characteristics
output voltage low 570 mV — 800 mV 0.5 mA ≤ (ISDA1and ISCL1) ≤ 3.5 mA; vol1 TI datasheet, p. 10 — over recommended operating conditions, unless otherwise noted
cmti 25 GV/s 50 GV/s — SeeFigure 7-3; cmti TI datasheet, p. 10 — over recommended operating conditions, unless otherwise noted
channel count — 2 — Two isolated channels: clock and data lines (ISO1540 bidirectional, ISO1541 bidirectional data + unidirectional clock) TI datasheet, p. 1
03 — Alternatives

Closest matches to ISO1540

ISO7240C 16.5× lower propagation delay, 8.5× lower fall time, 3.5× lower input capacitance
Si8610BB-B-IS 6.8× lower fall time, 5.0× higher output current, 4.4× higher isolation voltage
Si8610BC-B-IS 6.8× lower fall time, 6.6× higher isolation voltage, 5.0× higher output current
ISO1211 5.2× lower power dissipation, 4.4× higher isolation voltage, 3.3× higher propagation delay
ADuM1200AR 4.4× higher isolation voltage, 3.0× higher propagation delay, 1.8× lower input capacitance
Si8230 11.4× higher power dissipation, 4.4× higher isolation voltage, 1.2× higher supply voltage range
ADuM1201ARZ 4.4× higher isolation voltage, 3.0× higher propagation delay, 1.8× lower input capacitance
ISO7220M 12.3× higher propagation delay, 7.0× lower input capacitance, 3.7× higher power dissipation
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