2-A Chopper-Type DC/DC Buck Converter: TB7107FN
The TB7107FN is a 2-A chopper-type DC/DC converter housed in a small PS-8 package. It operates from a 4.5-V to 20-V input voltage (VIN) range, much wider than its predecessors. Thus, the TB7107FN can operate directly from 12 V or 15 V supplied from an AC/DC power board in various stationary equipment. The TB7107FN provides high efficiency due to a bootstrapped supply voltage and the on-chip output stage that consists of high-speed, low-RON N-channel power MOSFETs.
Features
- Achieves high-current drive with only a few external components : IOUT=2A(max)
- Operating supply voltage : VIN = 4.5V to 20 V
- Adjustable output voltage : VFB = 0.8V±2.3% (@Tj=25°C)
- Provides a power solution with high efficiency :η= 88%(Typ.) (@VIN = 12V, VOUT=3.3V , IOUT =0.7A)
- A small multi-layer ceramic capacitor can be used for an output smoothing capacitor.
- Undervoltage lockout, thermal shutdown, overcurrent protection
- Soft-start time adjustable via an external capacitor
- Small surface-mount package with low thermal resistance(PS-8)
Application
- LCD TVs, plasma display panels, DVD/Blu-ray recorders, set-top boxes, projectors, copiers, amusement
Pin Configuration
| Pin No. | Pin Name | Description |
|---|---|---|
| 1 | BOOT | BOOT switch pin |
| 2 | VIN | Input pin |
| 3 | LX | Switching pin |
| 4 | GND | Ground pin |
| 5 | VFB | Output voltage feedback pin |
| 6 | COMP | Phase compensation pin |
| 7 | EN | Enable pin |
| 8 | SS | Soft-start pin |
Features of the PS-8 Package
- The TB7107FN in the PS-8 package is much smaller and thinner than 2-A counterparts in SOP-8 from competitors.
PS-8 features 73% less mount area & 50% less height than SOP-8.Package PS-8 SOP-8 Outline Dimensions
Lead pitch=0.65mm
Mount Area [Ratio] 8.1mm2 [0.27] 30mm2 [1] Height [Ratio] 0.8mm [0.5] 1.6mm typ. [1]
Application Example
* See the datasheet for the values of the resistors for setting output voltage(RFB1/RFB2).
The values shown at left are an example for VOUT = 3.3 V.
Efficiency (For reference only)
Block Diagram
Main Characteristics
| Part Number | Type | Operating Input Voltage VIN(V) |
Output Current IOUT(A) |
Output Voltage VOUT(V) |
Typical Switching Frequency fosc(kHz) |
Package |
|---|---|---|---|---|---|---|
| TB7107FN | Buck | 4.5 to 20 | 2.0 | Variable (VFB=0.8V±2.3%) |
380 | PS-8 |