MXP34063RT
Radiation-tolerant 1.5A buck-boost converter with 3V-40V input, 100krad(Si) tolerance, and high efficiency.
Product Overview
Description
The MXP34063RT is a radiation-tolerant buck-boost DC-DC converter capable of operating from input voltages above, below, or equal to the output voltage.
With a wide 3V to 40V input range, 1.5A switch current, and 100krad(Si) radiation tolerance, it serves satellite and military applications.
The device achieves up to 90% efficiency and includes comprehensive protection features for reliable operation in harsh environments.
Product Series
MXP
Primary Application
Satellite power systems
Key Features
- Radiation tolerant to 100krad(Si) TID
- Wide input voltage range 3V to 40V
- Buck, boost, and buck-boost operation
- 1.5A output switch current
- High efficiency up to 90%
- Current limiting protection
- Thermal shutdown protection
- Hermetic ceramic packages
Specifications
| Input Voltage | 3V to 40V |
|---|---|
| Output Voltage | 1.25V to 40V |
| Switch Current | 1.5A maximum |
| Efficiency | Up to 90% |
| Radiation Tolerance | 100 krad(Si) |
| Switching Frequency | 100kHz fixed |
| Protection | Current limiting, thermal shutdown |
| Temperature Range | -55°C to +125°C |
| Package | CERDIP-8, CFP-8 |
Applications
Satellite power systems
Electronic system design
Military avionics
Electronic system design
Battery-powered equipment
Battery and charging management
Industrial controls
Industrial automation and control
Power supply modules
Power conversion and supply
Portable instruments
Electronic system design
FAE Expert Insights
"The MXP34063RT is a workhorse DC-DC converter that I've used in numerous satellite power system designs. The 100krad(Si) radiation tolerance makes it suitable for most LEO and GEO missions. The buck-boost capability is particularly valuable in battery-powered systems where input voltage varies above and below the output as the battery discharges. In one satellite design, we used this part to generate 5V from a 6.8V to 10V battery range throughout the mission life. The 90% efficiency is excellent for a radiation-tolerant part - many competing parts only achieve 80-85% due to larger feature sizes used for radiation hardness. One consideration: the 100kHz switching frequency is lower than commercial parts, resulting in larger inductors, but this is typical for rad-tolerant designs. I recommend using 2oz copper and adequate thermal vias for the switching transistor. For output capacitors, use ceramic with X7R dielectric for stability across temperature."
Reliable radiation-tolerant converter for satellite power systems
— Dr. Wang Tao, BeiLuo
Frequently Asked Questions
What is the radiation tolerance of MXP34063RT?
MXP34063RT is radiation tolerant to 100krad(Si) total ionizing dose (TID) per MIL-STD-883 Method 1019. The device undergoes radiation lot acceptance testing (RLAT) to verify radiation hardness. Single event effects (SEE) characterization shows no destructive single event latch-up (SEL) up to LET of 85 MeV·cm²/mg. Single event transient (SET) performance is characterized and reported in the radiation test report. This radiation tolerance level is suitable for most LEO satellite missions (typically 10-50krad total dose over mission life) and GEO missions (typically 100krad over 15 years). For missions requiring higher radiation tolerance, contact Mxtronics for 300krad options.
100krad suitable for most LEO and GEO missions. Contact factory for higher radiation tolerance requirements.
How do I calculate the inductor value for MXP34063RT?
Inductor value calculation for MXP34063RT: L_min = (V_out × (V_in - V_out)) / (V_in × f_sw × I_ripple). Where I_ripple is typically 20-30% of I_out. For example: V_in = 12V, V_out = 5V, I_out = 500mA, f_sw = 100kHz, I_ripple = 150mA (30%). L_min = (5 × (12-5)) / (12 × 100k × 0.15) = 35 / 180000 = 194μH. Use standard value 220μH with saturation current >1.5x I_out. For boost configuration, use L_min = (V_in² × (V_out - V_in)) / (V_out × f_sw × I_ripple × V_in). Always verify inductor saturation current rating exceeds peak switch current.
Calculate minimum inductance using formula. Use next standard value higher. Verify saturation current rating >1.5x output current.
What efficiency can I expect in actual operation?
MXP34063RT efficiency varies with input voltage, output voltage, and load current. Typical efficiency: Buck mode (12V to 5V): 85-90% at 50-100% load. Boost mode (5V to 12V): 80-85% at 50-100% load. Buck-boost mode (12V to 12V): 75-80% at 50-100% load. Efficiency decreases at light loads (<20%) due to quiescent current. Efficiency also decreases with larger input-output voltage differences. For highest efficiency, operate in buck mode when possible, and keep load current above 20% of maximum. Use synchronous rectification (external Schottky across internal diode) for 3-5% efficiency improvement.
Expect 85-90% in buck mode, 80-85% in boost mode. Operate above 20% load for best efficiency.
Can MXP34063RT be used for battery charging?
MXP34063RT can be configured for battery charging with appropriate external circuitry. For lithium-ion charging, you need: 1) Current sense resistor to monitor charge current. 2) Voltage feedback divider to set charge voltage (typically 4.2V per cell). 3) External control circuit (MCU or dedicated charger IC) to implement CC-CV charging profile. 4) Temperature monitoring for safety. The converter provides the power stage, but the charging algorithm must be implemented externally. For simple applications, constant voltage charging with current limiting may be sufficient. For multi-cell batteries, ensure proper cell balancing. Always include safety features like overvoltage protection and overtemperature shutdown.
Use with external control circuit for CC-CV charging. Implement safety features including temperature monitoring.
What are the key layout considerations for MXP34063RT?
PCB layout guidelines for MXP34063RT: 1) Keep high-current switching loop (input cap, switch, inductor) as small as possible to minimize EMI. 2) Place input capacitor close to VCC and ground pins with short, wide traces. 3) Use wide traces for power paths (switch, inductor, output cap). 4) Separate power ground from signal ground, connecting at a single point. 5) Place output capacitor close to load for best transient response. 6) Use thermal vias under the IC for heat dissipation. 7) Keep feedback divider traces away from switching nodes. 8) Use ground plane for shielding and low impedance return. For radiation-tolerant designs, use ceramic capacitors with X7R dielectric for stability across temperature.
Minimize switching loop area. Use short, wide traces. Separate power and signal grounds. Use thermal vias.