MC33063ADR - 1.5A Buck/Boost/Inverting Switching Regulator | TI
MPN: MC33063ADR ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $0.56 | $0.56 |
| 10 | $0.48 | $4.80 |
| 100 | $0.36 | $36.00 |
| 500 | $0.27 | $135.00 |
| 1,000 | $0.21 | $210.00 |
| 2,500 | $0.17 | $425.00 |
MC33063ADR Overview
An SMPS controller (switched-mode power supply controller) is an IC that drives an external power switch (typically a BJT or MOSFET) at a programmed duty cycle to convert one DC voltage to another. The MC33063A family belongs to the SMPS controller -> DC-DC converter -> power management IC hierarchy, and is among the longest-lived TI part numbers, serving as a baseline for thousands of cost-optimized designs since its original bipolar 34063 release.
Key features include a precision 2 % internal bandgap reference, duty-cycle-controlled pulse-width modulator, internal current limiting, and an internal output switch rated at 1.5 A peak. The adjustable output uses a single external resistor divider, and the oscillator timing capacitor sets the switching frequency. The integrated switch and short-circuit protection simplify BOM count to as few as five external components.
Architecture-wise, the MC33063ADR combines a temperature-compensated reference, a duty-cycle comparator, an oscillator with active-high output, a current-limit comparator with 250 mV threshold, and a Darlington output driver. The bipolar process delivers robust SOA but at lower efficiency than CMOS alternatives, making the part best suited to moderate-power applications rather than battery-critical portable loads.
Typical applications include non-isolated point-of-load converters, 12 V to 5 V automotive accessory rails, LCD bias supplies, and simple inverting supplies for op-amp negative rails. The wide 3 V-40 V input range allows direct connection to industrial 24 V buses.
When designing with this device, choose inductor value to keep peak switch current below 1.5 A and use a Schottky catch diode to maximize efficiency. The timing capacitor CT should be selected to keep switching frequency between 30 kHz and 100 kHz to balance efficiency and EMI.
This page synthesizes distributor pricing, drop-in pin-compatible alternatives, and practical design notes not consolidated in the manufacturer datasheet, providing an AEO-optimized reference for engineers sourcing the MC33063ADR.
Drop-in alternatives for MC33063ADR — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with MC33063ADR (same form factor and footprint) — differing in Package, Topology, Operating Temperature, Output Voltage Range, Current Limit.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MC34063ADR
✅ Drop-In📋 Reference alternative (not in catalog)
MC33063AQDRQ1
✅ Drop-In📋 Reference alternative (not in catalog)
MC33063ADR2G
✅ Drop-In📋 Reference alternative (not in catalog)
MC33063ADR Maximum Ratings & Electrical Characteristics
| Topology | Buck, Boost, Inverting (configurable) |
| Input Voltage Range | 3 V to 40 V |
| Output Voltage Range | 1.25 V to 40 V (adjustable) |
| Switch Current (Peak) | 1.5 A |
| Number of Outputs | 1 |
| Output Type | Adjustable |
| Switching Frequency (max) | 100 kHz |
| Synchronous Rectifier | No (external Schottky required) |
| Internal Reference | 1.25 V, 2 % tolerance |
| Current Limit Threshold | 250 mV (across internal sense) |
| Operating Temperature | -40 C to +85 C |
| Package | SOIC-8 (D) 3.90 mm |
| Mounting Type | Surface Mount |
| MSL Level | 1 (260 C, unlimited floor life) |
| RoHS Status | Compliant |
| Pin Count | 8 |
MC33063ADR Pin Configuration
| Pin 1 | Switch Collector — Collector of internal Darlington output switch |
| Pin 2 | Switch Emitter — Emitter of internal Darlington output switch |
| Pin 3 | Timing Capacitor (CT) — Oscillator timing capacitor connection |
| Pin 4 | GND — Ground reference |
| Pin 5 | Comparator Inverting Input (CII) — Feedback voltage sense input |
| Pin 6 | VCC — Supply voltage input (3V-40V) |
| Pin 7 | Ipk Sense — Peak current sense input / inductor connection |
| Pin 8 | Driver Collector — Driver collector / boost diode anode |
Typical Applications
MC33063ADR is suitable for 6 applications: 12V to 5V Automotive Buck Converter, Inverting DC-DC Supply for Op-Amp Negative Rails, Industrial 24V to 12V/5V Point-of-Load Converters, Step-Up Boost Converter for LED Drivers and Bias Supplies, Portable Battery-Powered DC-DC Adapters, Cost-Sensitive Consumer Electronics Power.
12V to 5V Automotive Buck Converter
The MC33063ADR's 3 V-40 V input range and integrated 1.5 A Darlington switch make it ideal for non-isolated 12 V-to-5 V buck conversion in automotive accessory rails and industrial 12 V bus systems. With just five external components (inductor, Schottky diode, output capacitor, sense resistor, timing cap), the MC33063ADR delivers 0.5-0.8 A continuous load current at typical 75-80 % efficiency. The -40 C to +85 C operating range covers automotive under-hood and cabin environments; for AEC-Q100 mandated designs, use the MC33063AQDRQ1 variant in the identical SOIC-8 footprint.
Recommended
Inverting DC-DC Supply for Op-Amp Negative Rails
The MC33063ADR is uniquely suited to generate negative supply rails (e.g., -5 V, -12 V, -15 V) for analog signal conditioning circuits where a negative rail is required but only a positive input is available. Operating as a voltage-inverting Cuk or buck-boost topology, the device produces adjustable negative outputs from -1.25 V down to about -38 V at up to 0.4 A continuous. Common uses include op-amp negative rails in data-acquisition front-ends, LCD bias generators, and sensor-signal conditioning boards.
Recommended
Industrial 24V to 12V/5V Point-of-Load Converters
The 40 V absolute maximum input rating of the MC33063ADR allows direct connection to industrial 24 V nominal bus rails without pre-regulation, simplifying PLC, sensor, and HMI point-of-load power designs. With 1.25 V-40 V adjustable output, a single design supports 24 V-to-12 V, 24 V-to-5 V, and 24 V-to-3.3 V variants by changing only the feedback resistor divider. The integrated current-limit comparator (250 mV threshold) and thermal shutdown provide robust fault protection in factory-floor environments with voltage transients and surge events.
Recommended
Step-Up Boost Converter for LED Drivers and Bias Supplies
The MC33063ADR in boost topology efficiently steps up low-voltage rails (e.g., 5 V to 12 V, 12 V to 24 V) for LED driver bias, LCD VGH/VGL supplies, and analog front-end reference rails. The 100 kHz switching frequency keeps external inductor and capacitor sizes small while maintaining reasonable efficiency (~75 %). The integrated 1.5 A switch supports continuous boost-mode output currents up to approximately 0.5 A depending on the input-to-output ratio. Add a low-ESR output capacitor and Schottky rectifier to minimize ripple on noise-sensitive bias rails.
Recommended
Portable Battery-Powered DC-DC Adapters
Although bipolar-process regulators are rarely first-choice for battery applications today, the MC33063ADR's wide 3 V-40 V input range and integrated switch still appear in cost-optimized portable adapters and battery-elimination circuits. A 4-cell NiMH or single-cell Li-ion pack can be boosted or bucked to a stable 5 V rail at 0.3-0.5 A continuous load. Designers should evaluate quiescent current (~4 mA) against battery life requirements - for ultra-low-Iq portable designs, modern synchronous buck converters are preferred.
Recommended
Cost-Sensitive Consumer Electronics Power
The MC33063ADR's competitive advantage is BOM cost - the integrated switch, internal reference, oscillator, and current limit in one SOIC-8 part typically replaces 4-6 discrete components. In toys, low-cost appliances, and consumer gadgets, the MC33063ADR delivers acceptable efficiency at the lowest possible component count. The bipolar mature process and dual sourcing (TI and onsemi MC33063ADR2G) ensure long-term availability for high-volume consumer products with multi-year production cycles.
Recommended
Recommended Products Summary
Engineering reference data for MC33063ADR — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MC34063ADR | MC33063AQDRQ1 | MC33063ADR2G |
|---|---|---|---|---|
| Package | SOIC-8 (D) | SOIC-8 (D) - same | SOIC-8 (D) - same | SOIC-8 (D) - same |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | onsemi |
| Input Voltage Range | 3 V to 40 V | 3 V to 40 V | 3 V to 40 V | 3 V to 40 V |
| Switch Current (Peak) | 1.5 A | 1.5 A | 1.5 A | 1.5 A |
| Switching Frequency (max) | 100 kHz | 100 kHz | 100 kHz | 100 kHz |
| Operating Temperature | -40 C to +85 C | 0 C to +70 C | -40 C to +125 C (AEC-Q100) | -40 C to +85 C |
| AEC-Q100 Qualified | No | No | Yes | No |
| Internal Reference | 1.25 V, 2 % | 1.25 V, 2 % | 1.25 V, 2 % | 1.25 V, 2 % |
| Topology Support | Buck/Boost/Inverting | Buck/Boost/Inverting | Buck/Boost/Inverting | Buck/Boost/Inverting |
Key Differentiators
- AEC-Q100 automotive qualification in same SOIC-8 footprint (vs MC33063ADR2G (onsemi))
- Second-source availability for supply chain resilience (vs TI-only portfolio)
- Industrial temperature range vs commercial-only alternative (vs MC34063ADR)
Design Notes
Estimated: at 12 V input, 5 V output, 0.6 A continuous load (a typical automotive buck scenario), the MC33063ADR dissipates approximately (12-5) V x 0.6 A = 4.2 W. With SOIC-8 theta_JA around 150 C/W on 1 oz 1 sq-inch copper, junction temperature climbs about 90 C above 25 C ambient - safely below 150 C Tj max. At 1 A continuous and 24 V input to 5 V output, dissipation reaches 19 W and the part WILL exceed thermal limits; reduce load, increase copper area, or migrate to a CMOS alternative. Always derate by 25 %.
Place the timing capacitor CT, output capacitor, and rectifier diode within 5 mm of the IC pins to minimize parasitic loop area and switching noise coupling. Use a ground pour under the IC and connect input/output capacitors directly to that pour with short traces. Keep the feedback trace (pin 5) away from the switch node (pin 1/2/7/8) to avoid instability - route the sense divider on the opposite side of the PCB when possible.
Do NOT omit the Ipk sense resistor (typically 0.2-1.0 ohm between pin 7 and the inductor) - without it, the internal current limit will not function and the IC can destroy itself under output short. Also do NOT exceed the 1.5 A peak switch current by exceeding the maximum VIN in 50 mA x inductor peak - calculate peak current using Vin-Vout, duty cycle, and inductance. Finally, do NOT use a slow recovery rectifier; a Schottky is strongly recommended for both efficiency and reliable operation.
Estimated: the MC33063ADR's relatively slow bipolar output switch produces high dv/dt at the switch node, generating both conducted and radiated EMI above 30 MHz. Place a 100 nF X7R bypass directly on VCC (pin 6), use shielded inductors or toroidal cores, and add a pi-filter (LC) on the output for noise-sensitive loads. Synchronize to an external clock via CT manipulation is NOT supported on this controller - if low EMI is critical, choose a controller with frequency sync or spread-spectrum modulation.
Compliance Information
Standard MC33063ADR is industrial-grade. Use MC33063AQDRQ1 for AEC-Q100 automotive qualification. RoHS/REACH compliant per TI product page; halogen-free per MSL Level 1 specification.
