Product Specifications
| SPECIFICATION |
|
| OUTPUT |
|
| Model | SD-350B | SD-350C | SD-350D |
| DC Voltage | 5V | 12V | 24V | 48V | 5V | 12V | 24V | 48V | 5V | 12V | 24V | 48V |
| Rated Current | 57A | 27.5A | 14.6A | 7.3A | 60A | 27.5A | 14.6A | 7.3A | 60A | 29.2A | 14.6A | 7.3A |
| Current Range | 0~57A | 0~27.5A | 0~14.6A | 0~7.3A | 0~60A | 0~27.5A | 0~14.6A | 0~7.3A | 0~60A | 0~29.2A | 0~14.6A | 0~7.3A |
| Rated Power | 285W | 330W | 350.4W | 350.4W | 300W | 330W | 350.4W | 350.4W | 300W | 350.4W | 350.4W | 350.4W |
| Ripple & Noise | 100mVp-p | 120mVp-p | 150mVp-p | 200mVp-p | 100mVp-p | 120mVp-p | 150mVp-p | 200mVp-p | 100mVp-p | 120mVp-p | 150mVp-p | 200mVp-p |
| Voltage Adj. Range | 4.5~5.5VDC | 11~16VDC | 23~30VDC | 43~53VDC | 4.5~5.5VDC | 11~16VDC | 23~30VDC | 43~53VDC | 4.5~5.5VDC | 11~16VDC | 23~30VDC | 43~53VDC |
| Voltage Tolerance | ±2.0% | ±1.0% | ±1.0% | ±1.0% | ±2.0% | ±1.0% | ±1.0% | ±1.0% | ±2.0% | ±1.0% | ±1.0% | ±1.0% |
| Line Regulation | ±0.5% | ±0.3% | ±0.2% | ±0.2% | ±0.5% | ±0.3% | ±0.2% | ±0.2% | ±0.5% | ±0.3% | ±0.2% | ±0.2% |
| Load Regulation | ±1.0% | ±1.0% | ±1.0% | ±1.0% | ±1.0% | ±1.0% | ±1.0% | ±1.0% | ±1.0% | ±1.0% | ±1.0% | ±1.0% |
| Setup, Rise Time | 300ms,50ms at full load |
| Voltage Range | 19~36VDC | 36~72VDC | 72~144VDC |
| Efficiency | 74% | 80% | 80% | 84% | 76% | 81% | 81% | 82% | 78% | 83% | 87% | 89% |
| DC Current | 14.4A/24V | 16A/24V | 17.6A/24V | 17.6A/24V | 7.6A/48V | 8.8A/48V | 9.0A/48V | 9.0A/48V | 6A/96V | 6A/96V | 6A/96V | 6A/96V |
| Over Load | 105~135% rated output power |
| Protection type: Shut down o/p voltage,re-power on to recover |
| Over Voltage | 5.75~6.75V | 16.8~20V | 31.5~37.5V | 53~65V | 5.75~6.75V | 16.8~20V | 31.5~37.5V | 53~65V | 5.75~6.75V | 16.8~20V | 31.5~37.5V | 53~65V |
| Protection type: Shut down o/p voltage,re-power on to recover |
| Over Temperature | 95℃± 5℃(TSW1) detect on main power transistor |
| Protection type: Shut down o/p voltage, recovers automatically after temperature goes down |
| Working Temp. | -20~+60℃ (Refer to “Derating Curve”) |
| Working Humidity | 20~90%RH non-condensing |
| Storage Temp., Humidity | -40~+85℃,10~95%RH |
| Temp. Coefficient | ±0.03%/℃ (0~50℃) |
| Vibration | 10~500Hz, 2G 10min./1cycle, 60min. each along X, Y, Z axes |
| Safety Standards | IEC60950-1CB approved by TUV(for D type only) |
| Withstand Voltage | I/P-O/P:1.5KVAC I/P-FG:1.5KVAC O/P-FG:0.5KVAC |
| Isolation Resistance | I/P-O/P,I/P-FG,O/P-FG:100M Ohms/500VDC /25℃ /70%RH |
| EMC Emission | Compliance to EN55022(CISPR22) Class B |
| EMC Immunity | Compliance to EN61000-4-2,3,4,6,8,light industry level,criteria A |
| Dimension | 215*115*50mm(L*W*H) |
| Weight | 1.1Kg |
| Packing | 12pcs/14.4Kg/0.92CUFT |
| NOTE |
|
| 1. All parameters NOT specially mentioned are measured at 24,48,96VDC input, rated load and 25℃ of ambient temperature. |
| 2. Ripple & noise are measured at 20MHz of bandwidth by using a 12” twisted pair-wire terminated with a 0.1uf & 47uf parallel capacitor. |
| 3. Tolerance : includes set up tolerance, line regulation and load regulation. |
| 4. The power supply is considered a component which will be installed into a final equipment. The final equipment must be re-confirmed that it still meets EMC directives. |
Product Introduction
The Leyu SD-350 series is a single-output DC-DC converter with a rated output power of 350W. It features a 2:1 wide input voltage range and supports three input voltage levels: 19–36V, 36–72V, and 72–144V (corresponding to sub-models B/C/D). The series offers four output voltage options: 5V, 12V, 24V, and 48V, with a maximum output current of up to 60A (for the 5V model). The converter is equipped with a built‑in DC fan for forced air cooling and operates stably in ambient temperatures from -20°C to +60°C. It is suitable for industrial, telecom, and vehicle‑mounted applications that demand high reliability.
![SD-350 Switch Power Supply]()
![SD-350 Switch Power Supply]()
![SD-350 Switch Power Supply]()
![SD-350 Switch Power Supply]()
Product Features
2:1 wide input voltage ratio, adaptable to different DC power systems
1500VAC input‑to‑output isolation, enhancing system safety
Built‑in protections: overload, short circuit, overvoltage, overtemperature. Overvoltage and overload protection require input power cycling to recover; overtemperature protection recovers automatically
Forced air cooling with built‑in DC fan – no external heatsink needed
100% full‑load burn‑in test to ensure consistency
Efficiency up to 89% (SD‑350D with 48V output), reducing heat loss
Adjustable output voltage (e.g., 12V model adjustable from 11–16V) to meet different load requirements
Product Advantages
Compared with similar DC‑DC modules, the Leyu SD‑350 series offers the following key advantages:
Wide input coverage: One series supports 24V, 48V, and 96V bus systems simultaneously, simplifying selection
Tight output accuracy: Typical line regulation ±0.2%~±0.5%, load regulation ±1.0%, output voltage tolerance as low as ±1.0%
Low ripple & noise: Only 100mVp‑p ripple on the 5V output and 200mVp‑p on the 48V output (20MHz bandwidth) – ideal for noise‑sensitive digital circuits
Complete EMC compliance: Meets EN55022 Class B radiated and conducted emission limits, and passes EN61000‑4 series immunity tests (light industrial level, criteria A)
Compact mechanical dimensions: 215×115×50mm (L×W×H), weight 1.1kg – easy for chassis integration
Product Applications
Industrial automation control cabinets (PLCs, servo drives)
Telecom base stations and DC remote power feeding systems
Railway and metro vehicle‑mounted DC power equipment
Battery backup power systems (voltage stabilization under fluctuating battery voltages)
Surveillance, photovoltaic monitoring, and other isolated DC supply scenarios
Frequently Asked Questions (FAQ)
Q: How to choose among the three sub‑models (B/C/D) of the SD‑350 series?
A: Decide based on your input voltage. Select model B for 19–36V input, model C for 36–72V input, and model D for 72–144V input. All models support the same output voltages (5/12/24/48V) – just specify the required output voltage when placing the order.
Q: Can I parallel outputs to increase total power?
A: Direct paralleling is not recommended. Each module has independent voltage regulation, and direct paralleling may cause current imbalance. For higher power, please consider other Leyu series with greater output power, or use an external current‑sharing circuit.
Q: How to recover from overload protection?
A: When the load exceeds 105%~135% of the rated output power, the module shuts down its output. You need to disconnect the input power, clear the overload fault, and then reapply input power – the module will resume normal operation.
Q: What is the operating temperature range? Does derating apply?
A: The operating ambient temperature is -20°C to +60°C. Derating is required between 50°C and 60°C (e.g., reduce output current at high temperatures). The datasheet provides a specific derating curve – follow it to avoid overtemperature protection.
Q: Does the product carry safety approvals?
A: Model D (72–144V input) has TUV CB certification based on IEC60950‑1. Models B and C are designed with reference to LVD requirements, but final certification must be confirmed for the complete end equipment.
Q: Does the fan run continuously or is it temperature‑controlled?
A: The built‑in DC fan runs continuously as soon as power is applied. It is not temperature‑controlled, ensuring reliable cooling across the entire load range.
Note: All technical parameters above are based on the Leyu official SD‑350 series datasheet (test conditions: nominal input voltage, rated load, 25°C ambient temperature). For actual use, please refer to the full datasheet for derating and installation instructions.
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SD-350.doc
English
