ZHCSHN0A February 2018 – April 2018 TPSM84424
PRODUCTION DATA.
- 1 特性
- 2 應用
- 3 說明
- 4 修訂歷史記錄
- 5 Pin Configuration and Functions
- 6 Specifications
-
7 Detailed Description
- 7.1 Overview
- 7.2 Functional Block Diagram
- 7.3
Feature Description
- 7.3.1 Adjusting the Output Voltage
- 7.3.2 Switching Frequency (RT)
- 7.3.3 Synchronization (CLK)
- 7.3.4 Output On/Off Enable (EN)
- 7.3.5 Input Capacitor Selection
- 7.3.6 Output Capacitor Selection
- 7.3.7 TurboTrans (TT)
- 7.3.8 Undervoltage Lockout (UVLO)
- 7.3.9 Soft Start (SS/TR)
- 7.3.10 Sequencing (SS/TR)
- 7.3.11 Power Good (PGOOD)
- 7.3.12 Safe Start-up into Pre-Biased Outputs
- 7.3.13 Overcurrent Protection
- 7.3.14 Thermal Shutdown
- 7.4 Device Functional Modes
- 8 Application and Implementation
- 9 Power Supply Recommendations
- 10Layout
- 11器件和文檔支持
- 12機械、封裝和可訂購信息
7.3.2 Switching Frequency (RT)
The switching frequency range of the TPSM84424 is 200 kHz to 1.6 MHz. The switching frequency can easily be set by connecting a resistor (RRT) between the RT pin and AGND. Use Equation 2 to calculate the RRT value for a desired frequency or simply select from Table 2.
The switching frequency must be selected based on the output voltage setting of the device and the operating input voltage. See Table 2 for the allowable output voltage range for a given switching frequency.
Equation 2. 
Table 2. VOUT Range vs Switching Frequency
| SWITCHING FREQUENCY | VIN = 5 V (±10%) | VIN = 12 V (±5%) | VIN = 15 V (±5%) | |||
|---|---|---|---|---|---|---|
| VOUT RANGE (V) | VOUT RANGE (V) | VOUT RANGE (V) | ||||
| min | max | min | max | min | max | |
| 250 kHz | 0.6 | 0.9 | 0.6 | 0.8 | 0.6 | 0.8 |
| 300 kHz | 0.6 | 0.9 | 0.6 | 0.9 | 0.7 | 0.9 |
| 350 kHz | 0.6 | 1.0 | 0.7 | 1.0 | 0.8 | 1.0 |
| 400 kHz | 0.6 | 1.2 | 0.7 | 1.2 | 0.9 | 1.2 |
| 450 kHz | 0.6 | 1.8 | 0.8 | 1.5 | 1.0 | 1.5 |
| 500 kHz | 0.6 | 2.0 | 0.9 | 1.8 | 1.1 | 1.8 |
| 550 kHz | 0.6 | 2.2 | 1.0 | 2.0 | 1.2 | 2.0 |
| 600 kHz | 0.6 | 2.5 | 1.1 | 2.5 | 1.4 | 2.3 |
| 650 kHz | 0.6 | 3.0 | 1.2 | 2.7 | 1.5 | 2.5 |
| 700 kHz | 0.6 | 3.5 | 1.3 | 3.0 | 1.6 | 2.8 |
| 750 kHz | 0.6 | 3.5 | 1.4 | 3.3 | 1.7 | 3.0 |
| 800 kHz | 0.7 | 3.5 | 1.5 | 3.6 | 1.8 | 3.3 |
| 900 kHz | 0.7 | 3.5 | 1.6 | 4.0 | 2.0 | 4.0 |
| 1.0 MHz | 0.9 | 3.5 | 1.8 | 6.0 | 2.2 | 4.8 |
| 1.1 MHz | 1 | 3.5 | 2.0 | 9.0 | 2.5 | 6.0 |
| 1.2 MHz | 1.1 | 3.5 | 2.2 | 9.0 | 2.7 | 8.0 |
| 1.3 MHz | 1.1 | 3.5 | 2.3 | 9.0 | 2.9 | 10 |
| 1.4 MHz | 1.2 | 3.5 | 2.4 | 9.0 | 3.1 | 10 |
| 1.5 MHz | 1.3 | 3.5 | 2.6 | 9.0 | 3.3 | 10 |
| 1.6 MHz | 1.4 | 3.5 | 2.8 | 9.0 | 3.5 | 10 |