PWM Control Step-up DC/DC Converter
ECL2119
General Description
The ECL2119 Series is a fixed frequency, constant current step-up DC/DC converter ideal for driving OLED. Output voltage of up to 22V can be derived, and from a li-ion battery supply ,the output voltage can be 12V drive OLED. A 2 ohm resistance of NMOS is integrated in the circuit , withstand voltage can support 22V, with a small SOT23-5 package saves PCB space and BOM cost.
Features
◆Input voltage range 2.7V—5.5V
◆Output voltage range up to 22V
◆Oscillation frequency 1.0MHz±20%
◆Efficiency 88%
◆Control PWM control
◆Stand-by Current ISTB=1.0uA(MAX)
◆Load capacitor 10uF,ceramic
◆LX limit Current 600mA
Applications
◆Mobil phones, PHS
◆PDAs
◆Digital still cameras
Package
◆SOT23-5L
Typical Application Circuit
Note: R1 and R2 can be adjusted by the voltage of VOUT and FB Pin; (when vout is equal to 12V,recommended resistor R1 = 875K, R2 = 100K,CP=100pF)
Ordering Information
R:Standard Feed
S:Reverse Feed
Denotes Oscillation Frequency:
B:1.0MHZ
B2:SOT23-5L
Marking Information
Part No | Package | Mark | Information |
ECL2119BB2X | SOT23-5L |
|
0-9,A-Z; 0-9,A-Z mirror writing,repeated(G,I,J,O,Q,W exception) |
Pin Configuration
Pin Number | Pin Name | Function |
1 | LX | Switch |
2 | VSS | Ground |
3 | FB | Voltage Feedback |
4 | CE | Chip Enable |
5 | VIN | Power Input |
Function Block Diagram
Absolute Maximum Ratings
Item | Symbol | Absolute maximum ratings | Unit | |
VIN Pin Voltage | VIN | Vss-0.3~Vss+7 | V | |
LX Pin Voltage | VLX | Vss-0.3~Vss+22 | ||
FB Pin Voltage | VFB | Vss-0.3~Vss+7 | V | |
CE Pin Voltage | VCE | Vss-0.3~Vss+7 | V | |
LX Pin Current | ILX | 600 | mA | |
Power Dissipation | PD | SOT23-5 | 250 | mW |
Operating Temperature range | Topr | -40~+85 | ℃ | |
Storage Temperature range | Tstg | -55~+125 |
Electrical Characteristics Ta=25℃, unless otherwise noted
Item | Symbol | Condtion | Min. | Typ. | Max. | Unit | Circuits |
FB Control Voltage | VFB | - | 1.205 | 1.23 | 1.255 | V | 1 |
Output Voltage range | VOUT | - | VIN | - | 22 | ||
Lx Operating Voltage range | VLX |
| - | - | 22 | ||
Operating Voltage range | VIN |
| 2.5 | - | 6 | ||
Stand-by Current | ISTB | VCE=0V、VLX=5V | - |
| 1 | uA | 3 |
Supply Current 1 | IDD1 |
| 500 | 1200 | 1500 | uA | 2 |
Supply Current 2 | IDD2 | VIN=VLX、VFB=2V | - | 90 |
| 3 | |
Oscillation Frequency | FOSC |
| 0.8 | 1.0 | 1.2 | MHz | 2 |
Maximum Duty Cycle | MAXDTY | VCONT=0.4V |
| 75 |
| % | 2 |
Efficiency | EFFI | VIN=3.6V;RLED=20Ω | - | 88 | - | % | 1 |
Current Limit | ILIM | VIN=3.6 |
| 600 |
| mA | 4 |
LX On Resistance |
| VIN=3.6V、VLX=0.4V |
| 2.0 |
| Ω | 2 |
LX Leak Current | ILXL |
|
| 0 | 1 | uA | 3 |
CE ‘H’ Voltage | VCEH |
| 1.1 |
|
| V | 2 |
CE ‘L’ Voltage | VCEL |
|
|
| 0.6 | V | 2 |
CE ‘H’ Current | ICEH | VIN=VLX、VFB=0.4V |
|
| 0.1 | uA | 3 |
CE ‘L’ Current | ICEL | VCE=0V、 VLX=5V |
|
| -0.1 | uA | 3 |
FB ’H’ Current | ICEH | VIN=VLX、VFB=0.4V |
|
| 0.1 | uA | 3 |
FB ’L’ Current | ICEL | VCE=0V、 VLX=5V |
|
| -0.1 | uA | 3 |
Test Circuits
Typical Performance Characteristics
Package Information
SOP23-5L