Part A
ISL81487LIBZ
Renesas Electronics America Inc.
- Lifecycle
- Active
- Stock
- 3479 Stückzahl
- Package
- SOIC-8
- Series
- Interface-Treiber, Empfänger, Transceiver
Replacement verdict
Not a drop-in replacement
The ISL81487LIBZ and ISL8105BCBZ-T are fundamentally different devices and cannot be used interchangeably. The ISL81487LIBZ is an RS-485/RS-422 transceiver, while the ISL8105BCBZ-T is a synchronous buck PWM controller. They differ in function, pinout, package, and electrical characteristics, making cross-replacement impossible without a complete redesign.
Different device function
Different pinout
Different package
Different supply voltage
Parts at a glance
Part B
ISL8105BCBZ-T
Renesas Electronics America Inc.
- Lifecycle
- Active
- Stock
- 6257 Stückzahl
- Package
- SOIC-8
- Series
- PMIC Spannungsregler für Spannungsregler für DC DC Switching Controller
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | ISL81487LIBZ | ISL8105BCBZ-T | Why it matters |
|---|---|---|---|
| Function | RS-485/RS-422 transceiver | Synchronous buck PWM controller | These devices perform completely different functions, so they are not functionally substitutable in any design. |
| Manufacturer | Renesas Electronics | Renesas Electronics | Same manufacturer, but this does not imply interchangeability between different product families. |
| Package / Mounting Type | 8-SOIC, surface mount | 10-SOIC, surface mount | Different pin counts and footprints prevent direct board-level replacement. |
| Supply Voltage Range | 4.5 V to 5.5 V | 5 V nominal (controller supply) | Operating voltage compatibility is essential for powering the device correctly in a target system. |
| Primary Interface / Control Type | Differential serial data (A/B bus pins) | PWM gate-drive outputs (UGATE/LGATE) | The signal interface determines what external circuitry the device can connect to and control. |
| Typical Application | Industrial data communication buses | DC-DC power conversion / voltage regulation | Application domain mismatch means the parts serve unrelated roles in a system. |
| Data Rate / Switching Frequency | Up to 250 kbps (slew-rate limited) | Fixed switching frequency (controller) | Speed and frequency specifications define the performance envelope and cannot be interchanged. |
| Number of Pins | 8 | 10 | Pin count difference directly affects PCB layout and socket compatibility. |
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Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | ISL81487LIBZ | ISL8105BCBZ-T |
|---|---|---|
| Supplier | - | Renesas Electronics America Inc |
| Part Status | Active | Obsolete |
| Output Type | - | Transistor Driver |
| Function | - | Step-Down |
| Output Configuration | - | Positive |
| Topology | - | Buck |
| Number of Outputs | - | 1 |
| Output Phases | - | 1 |
| Voltage - Supply (Vcc/Vdd) | - | 6.5V ~ 14.4V |
| Frequency - Switching | - | 300kHz |
| Duty Cycle(Max) | - | 100% |
| Synchronous Rectifier | - | Yes |
| Clock Sync | - | No |
| Control Features | - | Current Limit, Enable |
| Operating Temperature | -40°C ~ 85°C | 0°C ~ 70°C (TA) |
| Mounting Type | Surface Mount | Surface Mount |
| Type | Transceiver | - |
| Protocol | RS422, RS485 | - |
| Number of Drivers/Receivers | 1/1 | - |
| Duplex | Half | - |
| Receiver Hysteresis | 70 mV | - |
| Data Rate | 5Mbps | - |
| Voltage - Supply | 4.5V ~ 5.5V | - |
Frequently asked questions
Are the ISL81487LIBZ and ISL8105BCBZ-T interchangeable in a circuit design?
No. The ISL81487LIBZ is a half-duplex RS-485/RS-422 transceiver, while the ISL8105BCBZ-T is a synchronous buck PWM controller. They perform entirely different functions and are not pin-to-pin or functionally interchangeable.
What are the primary functions of the ISL81487LIBZ and ISL8105BCBZ-T?
The ISL81487LIBZ is a 5V-powered, half-duplex RS-485/RS-422 differential transceiver designed for bidirectional data communication over twisted-pair cables. The ISL8105BCBZ-T is a synchronous buck controller intended for DC-DC step-down voltage regulation in power supply designs.
What are the package types for the ISL81487LIBZ and ISL8105BCBZ-T?
The ISL81487LIBZ is offered in an 8-lead SOIC package. The ISL8105BCBZ-T is supplied in an 8-lead SOIC package with a tape-and-reel option (suffix -T). Both use SOIC-8, but their pinouts and functions differ.
Can the ISL81487LIBZ and ISL8105BCBZ-T operate from the same supply voltage?
The ISL81487LIBZ operates from a single 5V supply. The ISL8105BCBZ-T is a controller IC that typically operates from a 5V or 12V bias supply, depending on the application circuit, and is not a direct load-driving transceiver. Their supply requirements and operating conditions are not equivalent.
Do the ISL81487LIBZ and ISL8105BCBZ-T share any common applications?
No. The ISL81487LIBZ is used in industrial automation, data acquisition, and RS-485 networks. The ISL8105BCBZ-T is used in embedded DC-DC power converters, point-of-load regulators, and distributed power systems. Their application domains do not overlap.
Are the ISL81487LIBZ and ISL8105BCBZ-T available in the same temperature grade?
The ISL81487LIBZ is specified for the industrial temperature range of -40°C to +85°C. The ISL8105BCBZ-T is also specified for the industrial temperature range of -40°C to +85°C. However, this similarity does not imply functional compatibility.
Can the ISL81487LIBZ be used as a substitute for the ISL8105BCBZ-T in a power supply design?
No. The ISL81487LIBZ is a transceiver and cannot perform PWM control, gate driving, or voltage regulation. Substituting it for the ISL8105BCBZ-T would result in a non-functional power supply and potential damage to the circuit.