Overview
Description
The ISL81802 is a dual synchronous buck controller that generates two independent outputs or one output with two interleaved phases for a wide variety of applications in industrial and general purpose segments. With a wide input and output voltage ranges, the controller is suitable for telecommunication, data center, and computing applications.
The ISL81802 uses peak current mode control with phase interleaving for the two outputs. Each output has a voltage regulator, current monitor, and average current regulator to provide independent average voltage and current control. The internal Phase-Locked Loop (PLL) oscillator assures an accurate frequency setting from 100kHz to 1MHz, and the oscillator can be synchronized to an external clock signal for frequency synchronization and phase interleave paralleling applications. This PLL circuit can output a phase-shift-programmable clock signal that is expanded to three, four, and six phases with required interleaving phase shift.
The ISL81802 features programmable soft-start and accurate threshold enable functions along with a power-good indicator to simplify power supply rail sequencing. It also provides full protection features such as OVP, UVP, OTP, and average and peak current limit on both outputs to ensure high reliability.
The IC is packaged in a space-saving 32 Ld 5mm × 5mm TQFN or an easy to assemble 4.4mm × 9.7mm 38 Ld HTSSOP package. Both packages use an EPAD to improve thermal performance and noise immunity. The full feature design with low pin count makes the ISL81802 an ideal solution for quick time to market simple power supply designs.
Features
- Wide input voltage range: 4.5V to 80V
- Wide output voltage range: 0.8V to 76V
- Four MOSFET drivers with adaptive shoot-through protection
- Constant output voltage and output current feedback loop control
- Light-load efficiency enhancement
- Low ripple diode emulation and burst mode operation
- Programmable soft-start
- Supports startup into pre-biased rails
- Programmable frequency: 100kHz to 1MHz
- Supports current sharing with cascade phase interleaving
- External clock sync
- Clock out with accurate phase angle controlled by PLL or frequency dithering
- PGOOD indicator
- Output current monitor
- Selectable mode between PWM/DE/Burst
- Accurate EN/UVLO threshold: ±2%
- Low shutdown current: 5µA
- Complete protection: OCP (pulse by pulse and optional hiccup or constant current mode), OVP, OTP, and UVP
Comparison
Applications
Documentation
|
|
|
---|---|---|
Type | Title | Date |
Datasheet | PDF 2.61 MB | |
Manual - Development Tools | PDF 2.21 MB | |
Manual - Hardware | PDF 1.40 MB | |
3 items
|
Design & Development
Software & Tools
Boards & Kits
Models
ECAD Models
Schematic symbols, PCB footprints, and 3D CAD models from SamacSys can be found by clicking on the CAD Model links in the Product Options table. If a symbol or model isn't available, it can be requested directly from SamacSys.

Support
Support Communities
Support Communities
-
Definition of FET's switching time for ISL81806 or ISL81802
Could you please describe how do you define t_sw (switching time) in equation of the power loss of the upper GaN FET?I mean equation 15 from the datasheet of ISL81806 (or equation 16 from the datasheet of ISL81802).The user manuals of evaluation boards for SL81806 (or ISL81802 ...
Jun 12, 2023 -
ISL81802 as 8-Phase
Hi! From the link below, I knew that ISL81802 is for Si application and ISL81806 is for GaN application. link: ISL81806 as Quad Phase instead of Dual Phase My question is that is it possible to 8-phase 12v output capable of 80a using isl81802 or isl81806? Thanks!
May 15, 2025 -
ISL81806 as Quad Phase instead of Dual Phase
Hi! I happened to come across the ISL81806 which has the capability to do dual phase single output. I was curious to see if using two ISL81806 together to have a Quad Phase system would be doable, or if I should just stick with the Dual Phase of one instead ...
Nov 18, 2022
FAQs
-
Why is the ISL81802 rated at 80V, and is mainly used for 48V applications?
The 48V is not a constant voltage across the entire 5G base station or data center. There are long cables carrying that voltage with various loads attached to it. You can imagine there will be occasions like automotive load dump where the bus voltage simply goes up at transient. Most ...
Oct 21, 2020