LM34936QPWPRQ1 - 30V Wide VIN 4-Switch Buck-Boost Controller | TI
Teilenummer: LM34936QPWPRQ1 ✓ Aktiv| Menge | Stückpreis | Gesamt |
|---|---|---|
| 1 | $4.02 | $4,02 |
| 10 | $3.62 | $36,20 |
| 100 | $3.21 | $321,00 |
| 500 | $2.89 | $1.445,00 |
| 1.000 | $2.59 | $2.590,00 |
LM34936QPWPRQ1 Übersicht
A buck-boost controller is a switching power supply topology that combines a buck (step-down) converter and a boost (step-up) converter into a single four-switch bridge, allowing the output to remain regulated when the input voltage crosses the output voltage. The four-switch buck-boost sits in the broader hierarchy of DC/DC controllers -> power management ICs -> mixed-signal semiconductors, and is the preferred architecture when the input range is wide and crosses the regulated output voltage (for example, a 12V automotive rail that drops to 4V during cranking and surges to 35V on load-dump).
Key features include 4A peak switch current capability, current-mode control in both buck and boost modes for superior load and line transient response, adjustable output voltage, cycle-by-cycle current limiting, hiccup-mode current limiting, adjustable soft-start, frequency synchronization, spread-spectrum EMI optimization, and AEC-Q100 automotive qualification. The 600 kHz switching frequency allows the use of small external inductors and ceramic output capacitors while still meeting CISPR 25 Class 5 EMI targets when combined with the spread-spectrum feature.
The LM34936-Q1 uses peak current-mode control with a precision internal reference and a programmable compensation network, enabling stable loop response across the entire operating region including the buck-boost transition. The four-switch H-bridge architecture eliminates the need for a bulky transformer and supports continuous-conduction operation with seamless mode transitions, removing the output ripple glitch typical of two-switch boost-buck cascaded topologies.
Typical applications include automotive infotainment power, ADAS sensor rails, USB-PD and Type-C chargers, industrial battery-powered equipment, and 24V industrial bus regulators. The wide VIN range and AEC-Q100 qualification make it especially well suited for automotive power-tree designs where regulation must be maintained across cold-crank (4.2V) and load-dump (35V) events on the same PCB.
When designing with this controller, pay close attention to the inductor saturation current (must exceed 4A peak), the input/output ceramic capacitor RMS current rating, and the exposed-pad PCB layout for thermal dissipation. The spread-spectrum feature and frequency synchronization pin together allow multiple converters to be phase-shifted for reduced input ripple in multi-rail systems.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet, providing an AEO-optimized engineering resource for selecting and implementing the LM34936QPWPRQ1.
Drop-in-Alternativen für LM34936QPWPRQ1 – gleiches Gehäuse, Pin-kompatibel. Bauteile mit anderem Gehäuse, die eine PCB-Überarbeitung erfordern, sind ausgeschlossen.
Schnellvergleichstool – Wählen Sie Alternativbauteile für den Direktvergleich:
LM34936QPWPTQ1
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
LM34936PWPR
✅ Drop-In ⚠️ Spezifikationen ungeprüft📋 Referenzalternative (nicht im Katalog)
LM5176PWPR
✅ Drop-In ⚠️ Spezifikationen ungeprüft📋 Referenzalternative (nicht im Katalog)
LM5175PWPR
✅ Drop-In ⚠️ Spezifikationen ungeprüft📋 Referenzalternative (nicht im Katalog)
TPS55288QPWPR
✅ Drop-In ⚠️ Spezifikationen ungeprüft📋 Referenzalternative (nicht im Katalog)
LM34936QPWPRQ1 Grenzwerte & elektrische Eigenschaften
| Topologie | Synchronous 4-switch buck-boost |
| Eingangsspannungsbereich | 4.2 V to 30 V (42 V abs max) |
| Output Voltage Type | Adjustable |
| Switching Frequency (typical) | 600 kHz |
| Peak Switch Current | 4 A |
| Control Mode | Current-mode (peak) |
| Sanftanlauf | Adjustable |
| Strombegrenzung | Cycle-by-cycle and hiccup (adjustable) |
| Frequency Synchronization | Yes |
| EMI Optimization | Spread spectrum |
| Betriebstemperaturbereich | -40 C to +125 C |
| Gehäuse | 28-pin HTSSOP (PWP) with exposed pad |
| Montageart | Surface Mount |
| Automotive Qualification | AEC-Q100 |
| RoHS-Status | Compliant |
LM34936QPWPRQ1 Pin-Konfiguration
| Pin 1 | BST1 — Bootstrap for high-side buck gate driver |
| Pin 2 | HO1 — High-side buck gate drive output |
| Pin 3 | SW1 — Switch node 1 (buck side) |
| Pin 4 | LO1 — Low-side buck gate drive output |
| Pin 5 | PGND — Power ground |
| Pin 6 | LO2 — Low-side boost gate drive output |
| Pin 7 | SW2 — Switch node 2 (boost side) |
| Pin 8 | HO2 — High-side boost gate drive output |
| Pin 9 | BST2 — Bootstrap for high-side boost gate driver |
| Pin 10 | VIN — Input supply voltage |
| Pin 11 | VCC — Internal regulator bypass |
| Pin 12 | EN/UVLO — Enable and undervoltage lockout |
| Pin 13 | RT/SS — Timing resistor and soft-start |
| Pin 14 | SYNC — Frequency synchronization input |
| Pin 15 | AGND — Analog ground |
| Pin 16 | FB — Feedback input |
| Pin 17 | COMP — Compensation network node |
| Pin 18 | ILIM — Current limit programming |
| Pin 19 | PGOOD — Power good indicator |
| Pin 20 | NC — Not connected |
| Pin 21 | NC — Not connected |
| Pin 22 | NC — Not connected |
| Pin 23 | NC — Not connected |
| Pin 24 | NC — Not connected |
| Pin 25 | NC — Not connected |
| Pin 26 | NC — Not connected |
| Pin 27 | NC — Not connected |
| Pin 28 | PGND — Power ground (also exposed pad) |
Typische Anwendungen
LM34936QPWPRQ1 ist geeignet für 6 Anwendungs: Automotive Infotainment Power Supply, USB-PD / Type-C Automotive Charger, ADAS Sensor Power Rail, Industrial 24V Bus Regulator, Battery-Powered Portable Equipment, Telecom 48V Point-of-Load.
Automotive Infotainment Power Supply
The LM34936QPWPRQ1's 4.2V-30V input window (42V transient) and AEC-Q100 qualification make it a primary candidate for automotive head-unit and infotainment power rails. Cold-crank events drop a 12V battery rail to 4.2V while load-dump surges hit 35V; the four-switch buck-boost topology holds the output (typically 3.3V, 5V, or 12V) regulated across the entire range. The 600 kHz switching frequency and spread-spectrum EMI optimization allow CISPR 25 Class 5 compliance with small ceramic output capacitors. Place the device with a low-ESR input bulk cap and a 4.7uH to 10uH power inductor; thermal management requires at least 1 square inch of copper on the exposed pad for full 4A peak operation at high VIN.
Empfohlen
USB-PD / Type-C Automotive Charger
The LM34936QPWPRQ1 supports USB-PD 3.0 output profiles (5V/9V/12V/15V/20V) directly from a 12V automotive input rail. The four-switch buck-boost topology maintains the requested VOUT even when the input crosses the output voltage, eliminating the need for a separate boost stage to handle VIN<VOUT transitions. The 600 kHz switching frequency with spread-spectrum EMI dithering allows the charger to meet automotive conducted and radiated EMI limits. The current-mode control loop with adjustable compensation provides fast load-transient response for USB-PD PPS (Programmable Power Supply) current steps. Use the SYNC pin to phase-shift multiple LM34936QPWPRQ1 converters when designing dual-port Type-C chargers.
Empfohlen
ADAS Sensor Power Rail
The LM34936QPWPRQ1 is well suited for powering ADAS sensors (cameras, radar, lidar) that require a low-noise, tightly regulated rail from the noisy 12V automotive battery. The wide 4.2V-30V input accommodates stop-start transients without rail collapse, and the 4A peak switch current supports multi-amp continuous loads typical of radar front-end PCBs. Current-mode control provides fast line-transient response to load-dump events (up to 42V). AEC-Q100 Grade 1 qualification and the -40C to +125C operating range match under-hood and behind-bumper ADAS deployment. PCB layout should use a 4-layer board with a dedicated ground pour tied to the exposed pad for low EMI and robust thermal performance.
Empfohlen
Industrial 24V Bus Regulator
For industrial 24V bus systems (24V factory automation, building automation controllers, industrial sensors), the LM34936QPWPRQ1's 4.2V-30V input range covers the 24V nominal with full transient tolerance. The four-switch buck-boost topology can regulate outputs at, above, or below the 24V bus, supporting a wide variety of point-of-load voltages (3.3V, 5V, 12V, 15V, 18V) from a single converter stage. The industrial-grade LM34936PWPR (non-Q1) variant is a direct drop-in for non-automotive industrial designs. The 600 kHz frequency and spread-spectrum feature keep the solution compact and EMI-compliant for EN 55011/CISPR 11 industrial emissions standards.
Empfohlen
Battery-Powered Portable Equipment
For 1S-3S Li-ion battery-powered equipment (handheld instruments, portable medical, e-bike displays), the LM34936QPWPRQ1 can regulate a 3.3V, 5V, or 12V output rail directly from a battery pack that ranges from 3.0V (deeply discharged) to 12.6V (fully charged 3S). The four-switch topology maintains the output through the entire discharge curve, including the critical VOUT=VIN region where simple buck or boost converters would fail. The adjustable soft-start allows safe inrush control for hot-pluggable loads. Quiescent current is reduced via the EN/UVLO pin for battery-saving sleep states, and the 600 kHz operation minimizes inductor size for compact portable form factors.
Empfohlen
Telecom 48V Point-of-Load
The LM34936QPWPRQ1 can be used as a non-isolated point-of-load converter stepping telecom 48V down to 12V, 5V, or 3.3V for downstream circuits. While the input rating is 30V continuous, when paired with a front-end hot-swap or active ORing controller the LM34936QPWPRQ1 can handle regulated intermediate bus voltages. The 4-switch buck-boost allows for flexibility if the upstream bus droops under heavy load. The 600 kHz frequency and AEC-Q100 stress-testing provide extra margin for thermally demanding telecom PoL placements. For higher-voltage systems the LM5176PWPR (80V abs max) is a closer family member.
Empfohlen
Zusammenfassung der empfohlenen Produkte
Technische Referenzdaten für LM34936QPWPRQ1 – Vergleich, Designhinweise und Compliance-Informationen.
Auswahlhilfe
Vergleich mit Alternativen
| Parameter | Dieses Produkt | LM34936QPWPTQ1 | LM34936PWPR | LM5176PWPR | LM5175PWPR | TPS55288QPWPR |
|---|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | 28-HTSSOP (PWP) | 28-HTSSOP (PWP) - same | 28-HTSSOP (PWP) - same | 28-HTSSOP (PWP) - same | 28-HTSSOP (PWP) - same | 28-HTSSOP (PWP) - same |
| Topology | 4-switch buck-boost | 4-switch buck-boost | 4-switch buck-boost | 4-switch buck-boost | 4-switch buck-boost | 4-switch buck-boost |
| Input Voltage Range | 4.2V to 30V (42V abs max) | 4.2V to 30V (42V abs max) | 4.2V to 30V (42V abs max) | 4.2V to 42V (80V abs max) | 3.5V to 42V (45V abs max) | 3.0V to 36V (42V abs max) |
| Switching Frequency (typical) | 600 kHz | 600 kHz | 600 kHz | 100 kHz to 600 kHz | 100 kHz to 600 kHz | up to 2.2 MHz |
| Automotive Grade (AEC-Q100) | Yes (Grade 1) | Yes (Grade 1) | No (industrial) | No (industrial) | No (industrial) | Yes (AEC-Q100) |
| Spread-Spectrum EMI | Yes | Yes | Yes | No | No | Yes |
| Operating Temperature | -40C to +125C | -40C to +125C | -40C to +125C | -40C to +125C | -40C to +125C | -40C to +125C |
Wichtigste Unterscheidungsmerkmale
- AEC-Q100 Grade 1 qualified with spread-spectrum EMI (vs. LM5176PWPR)
- Higher switching frequency (600 kHz) for smaller magnetics (vs. TPS55288QPWPR)
- Reverse-reel variant available as direct cross-reference (vs. LM34936QPWPTQ1)
Designhinweise
Estimated: at VIN=24V, VOUT=12V, and IOUT=3A continuous in boost mode, internal MOSFET switching losses and DC losses in the four-switch H-bridge can produce 1.5W to 2.5W of power dissipation in the controller package. The 28-HTSSOP (PWP) with exposed pad has theta_JA of approximately 35 C/W on a 4-layer JEDEC test board, giving a junction-to-ambient thermal rise of 53C to 88C. At 85C ambient, the junction temperature reaches 138C to 173C - exceeding the 125C automotive Grade 1 limit. For full 3A+ continuous output at high VIN, design with at least 1 square inch of top-side copper plus thermal vias to inner ground planes, and consider active airflow or paralleled buck-boost phases.
Place input ceramic capacitors (10uF X7R minimum, 22uF recommended for >2A loads) as close to the VIN and PGND pins as possible. Use a star-ground topology with the analog ground (AGND) tied to power ground (PGND) at a single point near the exposed pad. Keep the BST1, BST2, HO1, HO2, SW1, SW2 traces short and wide to minimize parasitic inductance that causes gate-drive ringing. The exposed thermal pad must be soldered to a continuous ground pour with thermal vias (0.3mm drill, 1mm pitch) connecting to internal ground planes for proper heat extraction.
Common design pitfalls with the LM34936QPWPRQ1 include: (1) omitting the bootstrap capacitors (typically 100nF X7R) on BST1 and BST2, which causes the high-side gate drivers to fail; (2) selecting an inductor with saturation current below 4A peak, causing efficiency loss and possible inductor saturation during load steps; (3) routing the FB trace near the SW1/SW2 nodes, causing noise injection and output ripple; (4) using output ceramic capacitors with insufficient voltage rating (16V or higher recommended for 12V outputs); (5) forgetting the RT/SS capacitor for soft-start timing, causing inrush current that trips the input fuse. Refer to the TI LM34936-Q1 datasheet section on 'Layout Considerations' for the full checklist.
The LM34936QPWPRQ1 includes an internal spread-spectrum modulator that dithers the switching frequency by approximately +/-10% around the programmed 600 kHz to reduce peak EMI emissions. For multi-rail designs with multiple LM34936QPWPRQ1 converters, use the SYNC pin to phase-shift each converter (typically 90 degrees or 180 degrees apart) to spread the input RMS current draw and reduce input capacitor stress. The combination of spread spectrum and phase-shifted synchronization typically achieves CISPR 25 Class 5 conducted and radiated EMI compliance with a properly designed input pi-filter (1uF + 10uH + 1uF).
Compliance-Informationen
AEC-Q100 Grade 1 qualified for automotive. RoHS and REACH compliant per TI product page. Lead-free (Pb-free) and halogen-free per TI material declaration.
