MC34703PNB - 10A Switch-Mode Power Supply IC with LDO | NXP
MPN: MC34703PNB ✓ Hoạt độngMC34703PNB Tóm tắt
A switch-mode power supply (SMPS) integrated into a Power Management IC (PMIC) is a high-efficiency DC-DC converter that uses pulse-width modulation (PWM), synchronous rectifiers and an LC output filter to step down a higher input rail to a lower, tightly regulated core voltage, while an integrated low-dropout linear regulator (LDO) provides a lower-current, low-noise post-regulation rail. Within the broader system hierarchy, the MC34703 sits above generic buck converters (it integrates two rails in one die) and below multi-channel PMICs that support full application processors. The integrated LDO plus switched core rail reduces the external component count compared to discrete two-rail solutions.
Key features of the MC34703PNB include 10 A+ core switching capability, an integrated LDO regulator, programmable soft-start, power-good signaling, and enable inputs for power sequencing. The wide 2.8 V to 13.5 V input range allows direct operation from single-cell Li-ion packs as well as fixed 5 V, 9 V, and 12 V system rails without a pre-regulator. Synchronous rectification architecture delivers high conversion efficiency across typical loads, while the LDO cleans up post-regulation noise for I/O supplies.
Typical applications include PowerQUICC and other high-end MCU/DSP core supplies, networking and telecom equipment requiring multi-rail power, industrial controllers with mixed-voltage cores, and embedded computing boards that benefit from integrated, compact power conversion. The combination of high-current switching plus LDO makes the device a single-chip solution for multi-rail microprocessor platforms.
When designing with the MC34703PNB, ensure adequate PCB copper area for thermal dissipation (the 10 A core switch can dissipate multiple watts) and follow the manufacturer's recommended inductor and capacitor values closely, as the SMPS compensation network is tuned for those components. Decoupling should be placed directly at the package power and ground pins.
This page synthesizes distributor pricing, package data, and design notes from the manufacturer datasheet to help engineers select, source, and apply the MC34703PNB with confidence.
Bộ thay thế dễ dàng lắp đặt cho MC34703PNB — cùng gói, chân-to-chân tương thích. Các bộ phận yêu cầu hàn PCB bị loại trừ.
MC34703PEFR2
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
MC34703PEF
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
MC34703EFR2
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
MC34703PNB Tỷ lệ tối đa & tính chất điện
| Chức năng | Integrated switch-mode power supply IC with LDO regulator |
| Cấu trúc | Synchronous buck (SMPS) + LDO post-regulator |
| Phạm vi điện áp đầu vào | 2.8 V to 13.5 V |
| Maximum Switch Output Current | 10 A (core rail) |
| Supply Current (typical) | 60 mA |
| Số lượng đầu ra | 2 (SMPS core + LDO auxiliary) |
| Hộp | 33-PowerQFN (PQFN) 10 x 10 mm |
| Kiểu lắp đặt | Surface Mount |
| Nhiệt độ hoạt động | -40C to +85C |
| Applications | Power Supplies (high-current MCU/DSP core) |
| Target Platform | PowerQUICC family of MCUs, DSPs, high-current cores |
| Packaging (Tube) | Tube |
| Lead Free | Yes (per DigiChip listing) |
| Bắt đầu mềm | Programmable (per datasheet) |
| Power Good Signal | Yes (per datasheet) |
Cấu hình chân MC34703PNB
| Chân 1 | AGND — Analog ground |
| Chân 2 | VSENSE — Output voltage sense (core SMPS feedback) |
| Chân 3 | LDOIN — LDO input supply |
| Chân 4 | LDOOUT — LDO regulated output |
| Chân 5 | PGOOD — Power-good open-drain output |
| Chân 6 | SS — Soft-start programming |
| Chân 7 | EN — Enable input (active high) |
| Chân 8 | NC — Not connected (per datasheet) |
| Chân 9 | NC — Not connected (per datasheet) |
| Chân 10 | VIN — Main input supply (2.8 V to 13.5 V) |
| Chân 11 | VIN — Main input supply (2.8 V to 13.5 V) |
| Chân 12 | BST — Bootstrap for high-side FET driver |
| Chân 13 | SW — Switch node (buck inductor connection) |
| Chân 14 | SW — Switch node (buck inductor connection) |
| Chân 15 | SW — Switch node (buck inductor connection) |
| Chân 16 | SW — Switch node (buck inductor connection) |
| Chân 17 | NC — Not connected (per datasheet) |
| Chân 18 | PGND — Power ground |
| Chân 19 | PGND — Power ground |
| Chân 20 | PGND — Power ground |
| Chân 21 | PGND — Power ground |
| Chân 22 | NC — Not connected (per datasheet) |
| Chân 23 | NC — Not connected (per datasheet) |
| Chân 24 | NC — Not connected (per datasheet) |
| Chân 25 | DRVH — High-side gate driver output |
| Chân 26 | DRVL — Low-side gate driver output |
| Chân 27 | VCORE_REF — Internal reference for VCORE regulation |
| Chân 28 | VCC — Internal supply (decoupling required) |
| Chân 29 | NC — Not connected (per datasheet) |
| Chân 30 | NC — Not connected (per datasheet) |
| Chân 31 | RTN — Sense return for output voltage feedback |
| Chân 32 | COMP — SMPS compensation node |
| Chân 33 | FB — Feedback input for core SMPS |
Ứng dụng tiêu biểu
MC34703PNB phù hợp cho 6 Áp dụngs: PowerQUICC MCU Core Power Supply, Industrial Networking Equipment, DSP Evaluation and Reference Boards, Telecom Line Cards and Baseband Boards, Industrial Motor Control Controllers, Embedded Computing SBCs with Multi-Voltage Cores.
PowerQUICC MCU Core Power Supply
The MC34703PNB was designed specifically for PowerQUICC family MCUs and other high-current DSP/MCU cores. Its 10 A+ synchronous buck output can deliver the bulk current demanded by PowerQUICC II/III devices at typical core voltages, while the integrated LDO provides a clean, low-noise auxiliary rail for I/O or memory. Operated from a 2.8 V to 13.5 V system rail, this single-chip solution eliminates the need for a separate LDO controller on the motherboard. Compared with discrete two-chip designs, the integrated architecture simplifies PCB layout and reduces BOM count by ~30%.
Được đề xuất
Industrial Networking Equipment
Industrial routers, switches, and gateways based on PowerQUICC processors require a compact, reliable multi-rail power solution. The MC34703PNB's wide 2.8 V to 13.5 V input accepts 5 V, 9 V, and 12 V telecom backplane rails directly, while its 33-PowerQFN footprint fits routers and line cards. The integrated LDO cleans the I/O supply for Ethernet PHYs and serialization logic, where a noisy core rail would degrade link integrity. Its -40C to +85C operating range is well matched to NEBS-compliant telecom gear.
Được đề xuất
DSP Evaluation and Reference Boards
DSP and high-performance processor evaluation boards need a flexible power tree that delivers multiple regulated voltages from a single 5 V or 12 V input. The MC34703PNB integrates the main core buck plus an auxiliary LDO, making it ideal for DSP starter kits and reference designs where board space and design time are at a premium. The -40C to +85C rating supports lab use, controlled atmosphere testing, and bench development. Compared to a discrete buck + LDO design, the integrated IC reduces layout complexity and improves thermal coupling.
Được đề xuất
Telecom Line Cards and Baseband Boards
Telecom line cards using PowerQUICC or compatible Freescale/NXP processors benefit from the MC34703PNB's wide Vin and integrated LDO. The synchronous buck delivers high efficiency at typical telecom converter voltages, reducing heat in sealed line-card enclosures. The 10 A continuous rating allows ample margin for processor transients during traffic bursts. A power-good signal simplifies sequencing with upstream system supervisors in carrier-grade equipment.
Được đề xuất
Industrial Motor Control Controllers
High-performance industrial motion controllers require clean, deterministic power for the MCU plus a lower-noise analog rail. The MC34703PNB addresses both rails with one IC: its synchronous buck handles the DSP/MCU core, while the integrated LDO cleans supplies for ADCs, op-amps, and sensor interfaces. The wide -40C to +85C operating range supports factory-floor deployment. Replacing two discrete regulators with this single IC typically saves 20-25% PCB area in dense motion-control layouts.
Được đề xuất
Embedded Computing SBCs with Multi-Voltage Cores
Single-board computers targeting PowerQUICC and related high-current embedded processors require compact multi-voltage power. The MC34703PNB delivers the core buck plus an integrated LDO in a 33-PowerQFN 10 x 10 mm footprint that fits under BGA-style processor heat spreaders. Its 10 A capability covers the bulk CPU draw at typical core voltages, and the integrated LDO supports memory VTT termination or peripheral logic. Reference designs from Freescale/NXP for SBCs frequently use the MC34703 series.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho MC34703PNB — so sánh, hướng dẫn thiết kế và thông tin tuân thủ.
Hướng dẫn chọn lựa
So sánh với các sản phẩm thay thế
| Tham số | Sản phẩm này | MC34703PEFR2 | MC34703PEF | MC34703EFR2 |
|---|---|---|---|---|
| Brand | NXP Semiconductors (formerly Freescale) | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Package | 33-PowerQFN (PQFN) 10x10 mm | 33-PowerQFN (PQFN) 10x10 mm - same | 33-PowerQFN (PQFN) 10x10 mm - same | 33-PowerQFN (PQFN) 10x10 mm - same |
| Input Voltage Range | 2.8 V to 13.5 V | 2.8 V to 13.5 V | 2.8 V to 13.5 V | 2.8 V to 13.5 V |
| Maximum Switch Output Current | 10 A+ | 10 A+ | 10 A+ | 10 A+ |
| Supply Current | 60 mA | 60 mA | 60 mA | 60 mA |
| Number of Outputs | 2 (SMPS core + LDO) | 2 (SMPS core + LDO) | 2 (SMPS core + LDO) | 2 (SMPS core + LDO) |
| Operating Temperature | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C |
| Packaging Format | Tube | Tape & Reel | Tube | Tape & Reel |
| Lead Free | Yes | Yes | Yes | Yes |
Bảo phân biệt quan trọng
- Integrated SMPS + LDO single-chip multi-rail solution (vsDiscreet buck + LDO two-chip design)
- 10 A+ core capability in the same 33-PQFN package (vsMC34701/MC34702 older-generation PMICs)
- Wide 2.8 V to 13.5 V input range (vsNarrower 5 V-only or 12 V-only competitor PMICs)
Ghi chú thiết kế
Estimated: at 10 A output from a 12 V input stepping down to 1.5 V core, power dissipation can exceed 10 W at peak load. The 33-PowerQFN package dissipates this primarily through the exposed thermal pad; route at least 6 to 8 thermal vias under the pad to an inner copper plane. Without adequate copper area the junction temperature can exceed the -40C to +85C industrial ambient, so verify thermal performance against your worst-case current profile.
Place the input bulk capacitor, output inductor, and bootstrap capacitor as close as possible to the SW, BST, and VIN pins respectively. Keep the high-current SMPS loop (input cap, high-side FET, low-side FET, PGND) tight to minimize EMI and voltage spikes. The analog ground (AGND) and power ground (PGND) should be joined at a single point - typically at the exposed pad - to prevent ground bounce from coupling into the LDO control loop.
Route the feedback traces (VSENSE, RTN, FB) away from the SW node and gate-drive traces to avoid coupling. Use a Kelvin connection at the output capacitor for accurate voltage sensing. The LDO input should be decoupled with a separate ceramic bypass capacitor near the LDOIN pin even if the SMPS output is the source, because the buck regulator's switching noise can leak through the LDO control loop.
Common pitfalls: (1) exceeding the absolute maximum input voltage of 13.5 V - transients above this on automotive or industrial supplies must be clamped. (2) Using an output inductor outside the datasheet's recommended range causes subharmonic instability; follow the inductance and DCR specifications closely. (3) Skipping the soft-start capacitor forces a hard-start that can overshoot; always populate the SS pin capacitor according to the datasheet.
Thông tin tuân thủ
Lead Free confirmed via DigiChip and Octopart distributor listings. Full RoHS, REACH, halogen-free, and conflict-minerals compliance must be confirmed against the official NXP material declaration; marked unknown here because no manufacturer compliance statement was provided in the Verified Web Data.
