Package Information
| CAD Model: | View CAD Model |
| Pkg. Type: | QFN |
| Pkg. Code: | LFM |
| Lead Count (#): | 20 |
| Pkg. Dimensions (mm): | 3.99 x 3.99 x 0.90 |
| Pitch (mm): | 0.5 |
Environmental & Export Classifications
| Moisture Sensitivity Level (MSL) | 3 |
| Pb (Lead) Free | Yes |
| ECCN (US) | EAR99 |
| HTS (US) | 8542.39.0090 |
| RoHS (ISL85403FRZ) | Download |
Product Attributes
| Lead Count (#) | 20 |
| Carrier Type | Tray |
| Moisture Sensitivity Level (MSL) | 3 |
| Pb (Lead) Free | Yes |
| Pb Free Category | Pb-Free 100% Matte Tin Plate w/Anneal-e3 |
| Temp. Range (°C) | -40 to +105°C |
| Country of Assembly | MALAYSIA |
| Country of Wafer Fabrication | TAIWAN |
| Control Type | Current Mode |
| Input Voltage (Max) (V) | 40 |
| Input Voltage (Max) [Rail 1] (V) | 40 - 40 |
| Input Voltage (Min) (V) | 3 |
| Input Voltage (Min) [Rail 1] (V) | 3 |
| Length (mm) | 4 |
| Longevity | 2033 Dec |
| MOQ | 1470 |
| Output Current (Max) [Rail 1] (A) | 2.5 |
| Output Voltage (Max) (V) | 36 |
| Output Voltage (Max) [Rail 1] (V) | 36 |
| Output Voltage (Min) (V) | 0.8 |
| Output Voltage (Min) [Rail 1] (V) | 0.8 |
| Outputs (#) | 1 |
| POR | Yes |
| Parametric Category | Buck Regulators (Integrated FETs) |
| Peak Efficiency (%) | 96 |
| Pitch (mm) | 0.5 |
| Pkg. Dimensions (mm) | 4.0 x 4.0 x 0.90 |
| Pkg. Type | QFN |
| Qualification Level | Standard |
| Quiescent Current | 300 µA |
| SYNCH Capability | Yes |
| Simulation Model Available | iSim |
| Switching Frequency (KHz) | 2.2 - 2.2 |
| Switching Frequency Range (Typical) (kHz) | 200 - 2200 |
| Thickness (mm) | 0.9 |
| Topology [Rail 1] | Buck or Boost |
| Width (mm) | 4 |
Resources for ISL85403
Description
The ISL85403 is a 40V, 2. 5A synchronous buck or boost-buck controller with an integrated high-side MOSFET and low-side driver. In Buck mode, the ISL85403 supports a wide input range of 3V to 40V. In Boost-Buck mode, the input range can be extended down to 2. 5V and output regulation can be maintained when VIN drops below VOUT, enabling sensitive electronics to remain on in low input voltage conditions. The ISL85403 has a flexible selection of Forced PWM mode and PFM mode. In PFM mode, the quiescent input current is as low as 180µA (AUXVCC connected to VOUT). The load boundary between PFM and PWM can be programmed to cover wide applications. The low-side driver can either be used to drive an external low-side MOSFET for a synchronous buck or left unused for a standard non-synchronous buck. The low-side driver can also be used to drive a boost converter as a preregulator followed by a buck controlled by the same IC, which greatly expands the operating input voltage range down to 2. 5V or lower. ISL85403 offers robust current protection. It uses peak current mode control with cycle-by-cycle current limiting. It is implemented with frequency foldback under current limit condition; also, the hiccup overcurrent mode ensures reliable operations under harsh short conditions. The ISL85403 has comprehensive protections against various faults including overvoltage and over-temperature protection.