3A 30V Synchronous Buck Converter
EC3284S
General Description
The EC3284S is a monolithic synchronous buck regulator. The device integrates 95 mΩ MOSFETS that provide 3A continuous load current over a wide operating input voltage of 4.5V to 30V.Current mode control provides fast transient response and cycle-by-cycle current limit. An adjustable soft-start prevents inrush current at turn on.
Features
● 3A Output Current
● Wide 4.5V to 30V Operating Input Range
● Output Adjustable from 0.925V to 0.8VIN
● Up to 93% Efficiency
● Programmable Soft-Start
● Stable with Low ESR Ceramic Output Capacitors
● Fixed 340KHz Frequency
● Cycle-by-Cycle Over Current Protection
● Short-Circuit Protection
● Input Under Voltage Lockout
● Package：SOP 8L(Exposed PAD)
Applications
● Distributed Power Systems
● Networking Systems
● FPGA, DSP, ASIC Power Supplies
● Green Electronics/ Appliances
● Notebook Computers
Pin Configurations
3A 30V Synchronous Buck Converter
EC3284S
Typical Applications
Ordering Information
Part Number | Package | Marking | Marking Information |
EC3284SNMHR | SOP 8L (Exposed Pad) | 3284S LLLLL YYWWT | LLLLL is Lot Number YYWW is date code T is internal tracking code |
3A 30V Synchronous Buck Converter
EC3284S
Function Block Diagram
Absolute Maximum Ratings
Parameter | Symbol | Maximum | Units |
Supply Voltage | VIN | -0.3 to 30 | V |
SW Voltage | VSW | -0.3 to VIN+0.3 | V |
BS Voltage | VBS | VSW – 0.3V to VSW+6 | V |
EN / FB / COMP Voltage |
| -0.3 to 5 | V |
Continuous SW Current |
| Internally limited | A |
Junction to Ambient Thermal Resistance ( θJA ) |
| 20 | °C/W |
Junction to Ambient Case Resistance ( θJC ) | | 10 | °C/W |
SOP-8L(EP) Power Dissipation |
| Internal limit | W |
Storage Temperature | | -65 to 150 | ºC |
Maximum Junction Temperature |
| 150 | °C |
Note: Exceeding these limits may damage the device. Even the duration of exceeding is very short. Exposure to
absolute maximum rating conditions for long periods may affect device reliability。
3A 30V Synchronous Buck Converter
EC3284S
Recommended Operating Conditions
Parameter | Symbol | Value | Units |
Supply Input Voltage | VIN | 4.5 to +30 | V |
Operating Junction Temperature | TJ | -40 to +125 | °C |
Electrical Characteristics
(VIN = 12V, TJ = 25℃ unless otherwise specified.)
Parameter | Symbol | Conditions | Min | Typ | Max | Unit |
Feedback Voltage | VFB | 4.5V ≤ VIN ≤ 30V | 0.9 | 0.925 | 0.95 | V |
Feedback Overvoltage Threshold |
|
|
| 1.1 |
| V |
High-Side Switch-On Resistance* |
|
|
| 90 |
| mΩ |
Low-Side Switch-On Resistance* |
|
|
| 70 |
| mΩ |
High-Side Switch Leakage |
| VEN = VSW = 0V | , | 0.1 | 10 | uA |
Upper Switch Current Limit* |
| Min Duty Cycle | 3.8 | 4.5 |
| A |
Lower Switch Current Limit* |
| From Drain to Source |
| 1.2 |
| A |
COMP to Current Limit Trans conductance | GCOMP |
|
| 5.2 |
| A/V |
Error Amplifier Trans conductance | GEA | ΔICOMP = ±10uA |
| 900 |
| uA/V |
Error Amplifier DC Gain*A | VEA |
|
| 400 |
| V/V |
Switching Frequency | fSW |
| 300 | 340 | 380 | KHz |
Short Circuit Switching Frequency |
| VFB = 0V |
| 100 |
| KHz |
Minimum Duty Cycle | DMIN |
| 7.5 | |
| % |
Maximum Duty Cycle | DMAX |
| | 92 |
| % |
EN Shutdown Threshold Voltage |
| VEN Rising | 1.1 | 1.4 | 2 | V |
EN Shutdown Threshold Voltage Hysteresis |
|
|
| 180 |
| mV |
EN Lockout Threshold Voltage |
|
| 2.2 | 2.5 | 2.7 | V |
EN Lockout Hysteresis |
|
|
| 150 |
| mV |
Supply Current in Shutdown |
| VEN = 0V |
| 0.3 | 3.0 | uA |
IC Supply Current in Operation |
| VEN = 3V, VFB=1V |
| 1.3 | 1.5 | mA |
Input UVLO Threshold Rising | UVLO | VEN Rising | 3.8 | 4.0 | 4.4 | V |
Input UVLO Threshold Hysteresis |
|
|
| 150 |
| mV |
Soft-start Current |
| VSS = 0V |
| 6 |
| uA |
Soft-start Period |
| CSS =0.1uF |
| 15 |
| mS |
Thermal Shutdown Temperature* |
| Hysteresis=25°C |
| 155 |
| ℃ |
Note: * Guaranteed by design, not tested
Typical Applications
EC3284S Circuit, 3.3V/3A output