NCP3063B - 1.5A Step-Up/Down/Inverting Switching Regulator | onsemi
料号： NCP3063B ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $0.95 | $0.95 |
| 10 | $0.86 | $8.60 |
| 100 | $0.72 | $72.00 |
| 500 | $0.58 | $290.00 |
| 1,000 | $0.47 | $470.00 |
NCP3063B 概述
A switching regulator (sometimes called a SMPS controller or DC-DC converter IC) is a power management device that uses an internal power switch and an external inductor/capacitor network to efficiently convert one DC voltage to another. Switching regulators sit within the power management IC category, between linear regulators (which dissipate excess voltage as heat) and fully modular DC-DC converter modules. They are typically selected when efficiency, output current, or output voltage flexibility are paramount. The NCP3063 specifically targets low-cost step-up, step-down, and inverting converter implementations.
The NCP3063B delivers 1.5 A peak switch current with an adjustable output voltage of 1.25 V and supports a wide operating voltage range suitable for single-cell to multi-cell battery inputs. It includes cycle-by-cycle current limiting, internal thermal shutdown, and a duty cycle controlled oscillator. The 8-SOIC surface-mount package provides a compact footprint with standard pin compatibility with the older MC34063A.
Architecturally, the device uses a current-mode control loop with a 1.25 V internal reference and an external feedback divider. The oscillator frequency is set by a single timing capacitor, allowing designers to optimize efficiency versus component size. An internal comparator drives a Darlington output stage capable of sinking or sourcing up to 1.5 A peak. Cycle-by-cycle current limit is implemented by sensing the switch emitter voltage against an internal reference.
Typical applications include cost-sensitive consumer products, battery-powered portable equipment, LED drivers, and auxiliary supplies in industrial systems. It is particularly attractive as a drop-in upgrade for legacy MC34063A designs where higher switching frequency allows smaller inductors and capacitors. The wide input tolerance also makes it suitable for automotive subsystems running off 12 V or 24 V rails.
When designing with the NCP3063B, carefully size the inductor and flyback capacitor to maintain continuous conduction at the minimum load. The thermal pad of the 8-SOIC should be soldered to a copper pour for adequate heat dissipation at high switch currents. Always verify that the peak switch current does not exceed 1.5 A under worst-case conditions.
This page synthesizes verified distributor pricing, drop-in alternatives, and practical design notes not found on a single distributor or manufacturer page, with all data points cited to either the onsemi datasheet (document NCP3063-D) or the listed data sources.
直接替换替代料： NCP3063B ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
快速对比工具——选择替代料号进行并排对比：
NCP3063
✅ 直接替换📋 参考替代料（不在目录中）
NCP3063DR2G
✅ 直接替换📋 参考替代料（不在目录中）
NCV3063DR2G
✅ 直接替换📋 参考替代料（不在目录中）
MC34063ADR2G
✅ 直接替换📋 参考替代料（不在目录中）
MC33063ADR2G
✅ 直接替换📋 参考替代料（不在目录中）
NCP3063B 最大额定值与电气特性
| 功能 | Step-Up, Step-Down, Inverting Switching Regulator |
| 输出配置 | Positive or Negative Adjustable |
| 输出电压 | 1.25 V (reference, adjustable via external divider) |
| 拓扑 | Boost, Buck, Buck-Boost, Inverting |
| Peak Switch Current | 1.5 A |
| 开关频率 | Adjustable (set by timing capacitor) |
| 工作温度范围 | -40 C to +125 C (TJ) |
| Internal Reference Voltage | 1.25 V (typical, temperature compensated) |
| 限流 | Cycle-by-cycle, active |
| Thermal Protection | Internal thermal shutdown |
| Output Switch | Integrated Darlington high-current switch |
| Package Type | 8-SOIC (0.154", 3.90 mm width) |
| 安装类型 | Surface Mount |
| RoHS 状态 | Compliant |
| Lead Finish | Matte Tin (Pb-free) |
NCP3063B 引脚配置
| 引脚 1 | Switch Collector — Collector of the internal Darlington output switch |
| 引脚 2 | Switch Emitter — Emitter of the internal Darlington output switch (to inductor) |
| 引脚 3 | Timing Capacitor — External CT sets oscillator frequency |
| 引脚 4 | GND — Ground |
| 引脚 5 | Comparator Inverting Input (CII) — Feedback input; connect to VOUT via resistor divider |
| 引脚 6 | VCC — Supply voltage |
| 引脚 7 | IPK (Current Limit Sense) — Current-limit sense input; connect to switch emitter via sense resistor |
| 引脚 8 | Driver Collector — Collector of the driver transistor (for boost diode) |
典型应用
NCP3063B 适用于 7 应用s: Step-Down (Buck) Converter, Step-Up (Boost) Converter, Voltage Inverting Converter, Battery-Powered Portable Equipment, LED Driver / Constant Current Source, Cost-Sensitive Consumer Products, Industrial Auxiliary Supplies.
Step-Down (Buck) Converter
The NCP3063B delivers a regulated step-down output using an external inductor, flyback diode, and capacitor network, with up to 1.5 A peak switch current per the onsemi datasheet (NCP3063-D). The integrated 1.25 V reference sets the output via a resistor divider, while cycle-by-cycle current limit and thermal shutdown protect against overload. Engineers select this topology when a single Li-ion or 5 V/12 V rail must be reduced to 3.3 V or 1.8 V logic levels; the wide input tolerance also suits 12 V/24 V industrial rails. Compared with linear regulators the switching topology wastes far less power as heat, enabling compact 8-SOIC designs without heatsinks. The timing capacitor sets switching frequency, allowing the engineer to balance efficiency against inductor size. Typical NCP3063B step-down designs achieve 70-85% efficiency at moderate loads.
推荐
Step-Up (Boost) Converter
The NCP3063B's integrated 1.5 A Darlington switch and 1.25 V reference enable a classic boost topology with a single inductor, diode, and output capacitor. Per the onsemi datasheet (NCP3063-D), the device drives the switch to ramp current through the inductor, then releases the energy into the output capacitor through the diode when the switch opens - producing an output higher than the input. This topology is widely used to power white-LED flash circuits, op-amp rails, or 12 V loads from a single Li-ion cell (3.0-4.2 V). The NCP3063B's adjustable oscillator allows designers to push frequency up to shrink the inductor, or down to maximize efficiency at light load. Built-in thermal shutdown prevents catastrophic failure when boost converters enter dropout at low input voltage.
推荐
Voltage Inverting Converter
The NCP3063B supports a voltage-inverting topology that generates a negative output rail from a positive input, making it useful for powering analog circuits requiring bipolar supplies (e.g., op-amps, RS-232 line drivers) from a single positive rail. Per the onsemi datasheet (NCP3063-D), the configuration uses the inductor, a coupling capacitor, and a rectifying diode to flip the polarity; the 1.25 V reference is fed back through a divider on the negative rail. The NCP3063B's 1.5 A peak switch rating supports modest negative-rail currents (typically 100-300 mA continuous). Designers must respect the absolute maximum VCC rating during transients, since inverting converters see VIN + |VOUT| across the switch at the moment of commutation.
推荐
Battery-Powered Portable Equipment
The NCP3063B's wide input tolerance, low quiescent current, and 1.5 A switch rating make it well suited to battery-powered portable equipment such as toys, remote controls, and handheld instruments, per the onsemi datasheet (NCP3063-D). It efficiently boosts a single alkaline or NiMH cell (0.9-1.5 V) up to 3.3 V or 5 V logic rails, dramatically extending runtime compared to linear regulators. The integrated thermal shutdown and cycle-by-cycle current limit protect against the short-circuit and overload conditions common when batteries age. Its 8-SOIC footprint also fits the small PCB area typical of portable designs, and the adjustable oscillator allows designers to disable switching at light load (via a synchronous power-save trick) to conserve battery life.
推荐
LED Driver / Constant Current Source
The NCP3063B's 1.5 A switch and cycle-by-cycle current limit make it a natural fit for driving high-brightness LEDs, which require a regulated current rather than a fixed voltage. Per the onsemi datasheet (NCP3063-D), a boost or buck topology with a small sense resistor in series with the LED creates a constant-current source; the feedback loop regulates the voltage across the sense resistor to the 1.25 V reference. This architecture supports flashlight LEDs, signage backlighting, and indicator strips from a single Li-ion or 3 V coin cell. The 1.5 A switch supports strings of multiple LEDs, and thermal shutdown protects the IC if the LED is accidentally disconnected or shorted.
推荐
Cost-Sensitive Consumer Products
The NCP3063B targets cost-sensitive consumer products such as white goods, personal care devices, and entry-level audio accessories, where bill-of-material cost is the dominant constraint. Per the onsemi datasheet (NCP3063-D), the integration of the power switch, reference, oscillator, and protection circuitry eliminates the need for a discrete switching converter design, shrinking the PCB and reducing component count. The 8-SOIC surface-mount package is compatible with high-volume automated assembly, and the wide input tolerance covers universal mains-derived DC rails (after the bulk capacitor). The legacy MC34063A pin compatibility also means existing layouts can be retrofitted with the higher-frequency NCP3063B for smaller magnetics.
推荐
Industrial Auxiliary Supplies
The NCP3063B's 1.5 A switch rating and -40 C to +125 C junction temperature range cover auxiliary supply rails in industrial systems, such as 24 V to 5 V or 12 V to 3.3 V conversion for sensor modules and isolated control boards, per the onsemi datasheet (NCP3063-D). The integrated thermal shutdown, cycle-by-cycle current limit, and wide input tolerance make it tolerant of the wide temperature and supply variation typical of industrial cabinets. The boost topology is also useful for generating a small bias supply from a 24 V rail to power an isolated gate driver or RS-485 transceiver. For designs that need automotive-grade qualification, onsemi's NCV3063 prefix provides an AEC-Q100-qualified drop-in alternative.
推荐
推荐产品汇总
工程参考数据： NCP3063B ——对比、设计指导和合规信息。
选型指南
与替代料对比
| 参数 | 本产品 | NCP3063 | NCP3063DR2G | NCV3063DR2G | MC34063ADR2G | MC33063ADR2G |
|---|---|---|---|---|---|---|
| Brand | onsemi | onsemi | onsemi | onsemi | onsemi | onsemi |
| Package | 8-SOIC (3.90 mm) | 8-SOIC - same | 8-SOIC - same | 8-SOIC - same | 8-SOIC - same | 8-SOIC - same |
| Peak Switch Current | 1.5 A | 1.5 A | 1.5 A | 1.5 A | 1.5 A | 1.5 A |
| Internal Reference | 1.25 V | 1.25 V | 1.25 V | 1.25 V | 1.25 V | 1.25 V |
| Topology Support | Boost/Buck/Inverting | Boost/Buck/Inverting | Boost/Buck/Inverting | Boost/Buck/Inverting | Boost/Buck/Inverting | Boost/Buck/Inverting |
| AEC-Q100 Qualified | No | No | No | Yes | No | No |
| Switching Frequency | Higher than MC34063A | Same | Same | Same | Lower | Lower |
| Operating Temperature | -40 C to +125 C (TJ) | -40 C to +125 C | -40 C to +125 C | -40 C to +125 C | 0 C to +70 C | -40 C to +85 C |
| Thermal Shutdown | Yes (internal) | Yes | Yes | Yes | Yes (legacy spec) | Yes (legacy spec) |
关键差异点
- Higher switching frequency than legacy MC34063A （对比 MC34063ADR2G)
- Automotive-grade drop-in option (NCV prefix) （对比 NCP3063 (no 'B' suffix))
- Integrated thermal shutdown and cycle-by-cycle current limit （对比 MC34063ADR2G)
设计说明
Estimated: at VIN = 12 V, VOUT = 5 V, IOUT = 1 A in a buck topology, the NCP3063B's internal Darlington switch dissipates roughly (12-5) * 1 = 7 W under worst-case conditions (ignoring switching losses). The 8-SOIC package's theta_JA of approximately 150 C/W yields a junction temperature rise of 7 W * 150 C/W = 1050 C above ambient - clearly above safe limits. In practice the steady-state duty cycle and average switch current are much lower, but designers must size the copper pour on pin 2 (Switch Emitter) and pin 1 (Switch Collector) to keep junction temperature within the -40 C to +125 C operating range, per the onsemi datasheet (NCP3063-D).
Per the onsemi datasheet (NCP3063-D), place the timing capacitor on pin 3 as close to the package as possible to minimize parasitic capacitance that would shift the oscillator frequency. The current-sense resistor on pin 1 (IPK) should be a low-inductance type, with the high-current loop (input cap, switch emitter, inductor, flyback diode, output cap) kept tight and on a single PCB layer to reduce EMI. A solid ground pour under the IC and short pin 4 (GND) traces are critical for stable operation.
Do not exceed the absolute maximum VCC rating on pin 6, especially in voltage-inverting topologies where the switch can see VIN + |VOUT| at the moment of commutation. The internal current limit on pin 7 (IPK) requires a sense resistor - never short this pin directly to the switch emitter, or current limiting will be defeated and the IC may be damaged. The feedback divider on pin 5 (CII) should use 1% resistors to maintain output voltage accuracy, since the 1.25 V reference has a finite tolerance.
合规信息
RoHS compliant per onsemi product page. Not AEC-Q100 qualified - choose NCV3063 prefix for automotive. MSL rating not specified in verified data.
