The official datasheet reports a maximum output current of ~90 A and an operating supply range near 3 V–16 V for the ISL99390FRZ-TR5935, making it suitable for high-current point-of-load and multiphase power stages. This compact, fact-first brief condenses the datasheet highlights and the critical specs designers need to decide quickly whether the part fits a given high-current power design.
1 — Product snapshot: what the device is and why it matters (Background)
One-line definition
A high-current smart power stage / half-bridge driver intended for multiphase DC‑DC conversion and point‑of‑load regulation, integrating drive circuitry and current delivery capability to simplify board area and thermal management compared with discrete MOSFET solutions.
Typical application roles (where it’s used)
Typical uses include: multiphase VRMs for processors (high continuous current in a compact footprint); single‑phase 90 A point‑of‑load rails for ASICs and accelerators (dense power delivery); networking and telecom power modules where compact, high-current stages reduce board area and thermal resistance.
2 — ISL99390FRZ-TR5935: top-line key specs at a glance (Data analysis)
Electrical headline numbers (must-know specs)
Headlines from the official datasheet: maximum output current ≈ 90 A (device-level rating), recommended operating supply range ≈ 3 V to 16 V, and support for common output voltages used in point‑of‑load rails. Ranges shown in the datasheet should be treated as recommended operating windows versus absolute maximum ratings provided in the electrical tables. Verify the full electrical tables on the product datasheet for transient and derating conditions.
| Parameter | Specification Range | Conditions / Notes |
|---|---|---|
| Maximum Output Current | ~90 A Max | Device-level thermal limit |
| Operating Supply Voltage (VIN) | 3 V to 16 V | Recommended operating window |
| Package Footprint | QFN39 | Surface mount, exposed pad |
| Key Protections | OCP, OTP, UVLO | Integrated real-time reporting |
Package, mechanical and ordering basics
The part is provided in a QFN39-style package; the datasheet/part page contains the full mechanical drawing and recommended footprint. Moisture sensitivity level, reel/tray packaging, and minimum order quantities are listed on the official datasheet and part documentation—review those ordering metadata before procurement to confirm handling and assembly constraints.
3 — ISL99390FRZ-TR5935: electrical performance & protections (Data analysis)
Dynamic / switching characteristics & efficiency pointers
The datasheet includes switching and efficiency guidance tied to the reference controller and external components; switching frequency and resulting efficiency depend on the chosen controller topology and external inductor. Example curves typically show high efficiency at moderate loads with efficiency falling as switching losses rise at higher frequency or extreme current. For accurate design estimates use the official efficiency vs. load graphs and the electrical tables for conduction and switching loss contributors.
Built-in protections and telemetry
Protection features documented include over‑current protection, thermal shutdown, and undervoltage/overvoltage reporting. Fault reporting is provided via the device’s fault flag mechanism as described in the datasheet; consult the part page for whether flags are latched or open‑drain and for recommended fault handling in your controller firmware or supervision circuitry.
4 — PCB, thermal, and layout guidance (Method guide)
Recommended PCB layout and thermal management
The official layout guidance emphasizes a large thermal pad with multiple thermal vias to internal planes, wide copper pours for high‑current traces, and a low‑impedance ground. Where the datasheet specifies via counts and sizes, follow those exact recommendations; otherwise use best practices for high‑current QFN parts: large exposed pad, ≥6 thermal vias (staggered) of plated through type, and heavy copper pours tied to the pad to minimize thermal resistance.
Decoupling, gate-drive, and sensing recommendations
Recommended schematics show close‑placed input and output bulk/ceramic decoupling with low ESR and low ESL capacitors, gate‑drive bypass capacitors near the device, and sense resistor placement on the low‑side return for accurate current monitoring. If the datasheet gives ESR/ESL windows for capacitors, select caps within those ranges and follow placement rules to reduce loop inductance and ensure stable transient response.
5 — Typical application example, quick comparison and procurement checklist (Case + Action)
Typical application summary and quick schematic pointers
A common reference application is a single‑phase 90 A point‑of‑load regulator or a multiphase arrangement using multiple stages in parallel for higher total current. Reference designs pair the stage with a low‑DCR power inductor, accurate current sense resistor, input bulk and ceramic decoupling, and a compatible PWM controller; follow the reference schematic to ensure stable VOUT regulation and thermal balance across stages.
Quick procurement & evaluation checklist (what to verify before prototyping)
Before prototyping: confirm package compatibility with your PCB, verify max current and temperature derating, check moisture sensitivity and reel/tray packaging, and request the official datasheet and support files (EVM, BOM, Gerbers). Validate lead times and MOQs with suppliers and record the device datasheet and key specs for BOM signoff.
Summary
The ISL99390FRZ-TR5935 is a high‑current smart power stage rated for ≈90 A with a supply window around 3 V–16 V, offering a compact route to dense point‑of‑load and multiphase power delivery. For design decisions, download the official datasheet and confirm the detailed electrical tables, layout notes, and key specs before prototype.
Key summary
- Maximum output current ≈ 90 A and recommended operating supply ~3 V–16 V — check the official datasheet for transient and derating tables.
- QFN39 package with thermal pad; follow the datasheet mechanical drawing and thermal via recommendations for low thermal resistance and reliable assembly.
- Datasheet provides efficiency and switching guidance tied to reference designs; use recommended decoupling, gate‑drive bypassing, and current sense placement to match reference performance.
Frequently Asked Questions
What supply range does the ISL99390FRZ-TR5935 support and where is that documented?
The datasheet documents a recommended operating supply range near 3 V to 16 V; detailed operating conditions, absolute maxima, and recommended deratings are in the official product datasheet electrical tables. Use those tables when setting input rails and protections in your system.
How should I manage PCB thermal vias and copper for this power stage?
Follow the thermal pad and via guidance in the datasheet where provided. If specific counts are not listed, use a large exposed pad tied to internal planes, employ multiple plated through thermal vias (commonly ≥6, staggered), and maximize copper pour on power and return planes to reduce thermal resistance and minimize high‑current trace losses.
What protections and fault reporting does the datasheet describe for evaluation?
The product datasheet describes built‑in over‑current protection, thermal shutdown, and undervoltage/overvoltage reporting, with fault signaling via the device flag mechanism; check the datasheet for whether flags are latched or open‑drain and follow the recommended fault handling in reference schematics during evaluation.
What external decoupling components are recommended for high-current configurations?
High-current configurations require close-placed, low-ESR/ESL ceramic decoupling capacitors on both input (VIN) and output (VOUT) rails, alongside local gate-drive bypass capacitors. This minimizes loop inductance and ensures system stability under transient load steps.
