SLOS751D March   2013  – November 2018

PRODUCTION DATA.

1. Features
2. Applications
3. Description
4. Revision History
5. Pin Configuration and Functions
6. Specifications
7. Detailed Description
1. 7.1 Overview
2. 7.2 Functional Block Diagram
3. 7.3 Feature Description
4. 7.4 Device Functional Modes
5. 7.5 Programming
1. 7.5.1 Programming the Boost Voltage
2. 7.5.2 Programming the Boost Current Limit
3. 7.5.3 Programming the RAM
1. 7.5.3.1 Accessing the RAM
2. 7.5.3.2 RAM Format
4. 7.5.4 I2C Interface
6. 7.6 Register Map
8. Application and Implementation
1. 8.1 Application Information
2. 8.2 Typical Application
1. 8.2.1 Design Requirements
2. 8.2.2 Detailed Design Procedure
3. 8.2.3 Application Curves
3. 8.3 Initialization Setup
1. 8.3.1 Initialization Procedure
2. 8.3.2 Typical Usage Examples
9. Power Supply Recommendations
10. 10Layout
11. 11Device and Documentation Support
12. 12Mechanical, Packaging, and Orderable Information

• RGP|20
• RGP|20

#### 7.5.1 Programming the Boost Voltage

The boost output voltage is programmed through two external resistors as shown in Figure 23. The boost output voltage is given by Equation 1.

Equation 1.

where

• V(FB) = 1.32 V

V(BST) must be programmed to a value of 5.0 V greater than the largest peak voltage expected in the system to allow adequate amplifier headroom. Because the programming range for the boost voltage extends to 105 V, the leakage current through the resistor divider can become significant. It is recommended that the sum of the resistances R1 + R2 be greater than 400 kΩ. When resistor values greater than 1 MΩ are used, PCB contamination may cause boost voltage inaccuracy. Exercise caution when soldering large resistances, and clean the area when finished for best results. Table 2 shows examples on how to configure the device for different output voltages.

### Table 2. Boost Voltage Table

R1 R2 GAIN[1:0] V(BST) FULL SCALE PEAK VOLTAGE (V)
402 kΩ 18.2 kΩ 00 30 25
392 kΩ 9.76 kΩ 01 55 50
768 kΩ 13 kΩ 10 80 75
768 kΩ 9.76 kΩ 11 105 100