SNVSB23 March 2018 LP87521-Q1 , LP87522-Q1 , LP87523-Q1 , LP87524-Q1 , LP87525-Q1
PRODUCTION DATA.
- 1 Features
- 2 Applications
- 3 Description
- 4 Revision History
- 5 Device Comparison Table
- 6 Pin Configuration and Functions
- 7 Specifications
-
8 Detailed Description
- 8.1 Overview
- 8.2 Functional Block Diagram
- 8.3
Feature Descriptions
- 8.3.1 Multi-Phase DC/DC Converters
- 8.3.2 Sync Clock Functionality
- 8.3.3 Power-Up
- 8.3.4 Regulator Control
- 8.3.5 Enable and Disable Sequences
- 8.3.6 Device Reset Scenarios
- 8.3.7 Diagnosis and Protection Features
- 8.3.8 GPIO Signal Operation
- 8.3.9 Digital Signal Filtering
- 8.4 Device Functional Modes
- 8.5 Programming
- 8.6
Register Maps
- 8.6.1
Register Descriptions
- 8.6.1.1 OTP_REV
- 8.6.1.2 BUCK0_CTRL1
- 8.6.1.3 BUCK1_CTRL1
- 8.6.1.4 BUCK2_CTRL1
- 8.6.1.5 BUCK3_CTRL1
- 8.6.1.6 BUCK0_VOUT
- 8.6.1.7 BUCK0_FLOOR_VOUT
- 8.6.1.8 BUCK1_VOUT
- 8.6.1.9 BUCK1_FLOOR_VOUT
- 8.6.1.10 BUCK2_VOUT
- 8.6.1.11 BUCK2_FLOOR_VOUT
- 8.6.1.12 BUCK3_VOUT
- 8.6.1.13 BUCK3_FLOOR_VOUT
- 8.6.1.14 BUCK0_DELAY
- 8.6.1.15 BUCK1_DELAY
- 8.6.1.16 BUCK2_DELAY
- 8.6.1.17 BUCK3_DELAY
- 8.6.1.18 GPIO2_DELAY
- 8.6.1.19 GPIO3_DELAY
- 8.6.1.20 RESET
- 8.6.1.21 CONFIG
- 8.6.1.22 INT_TOP1
- 8.6.1.23 INT_TOP2
- 8.6.1.24 INT_BUCK_0_1
- 8.6.1.25 INT_BUCK_2_3
- 8.6.1.26 TOP_STAT
- 8.6.1.27 BUCK_0_1_STAT
- 8.6.1.28 BUCK_2_3_STAT
- 8.6.1.29 TOP_MASK1
- 8.6.1.30 TOP_MASK2
- 8.6.1.31 BUCK_0_1_MASK
- 8.6.1.32 BUCK_2_3_MASK
- 8.6.1.33 SEL_I_LOAD
- 8.6.1.34 I_LOAD_2
- 8.6.1.35 I_LOAD_1
- 8.6.1.36 PGOOD_CTRL1
- 8.6.1.37 PGOOD_CTRL2
- 8.6.1.38 PGOOD_FLT
- 8.6.1.39 PLL_CTRL
- 8.6.1.40 PIN_FUNCTION
- 8.6.1.41 GPIO_CONFIG
- 8.6.1.42 GPIO_IN
- 8.6.1.43 GPIO_OUT
- 8.6.1
Register Descriptions
- 9 Application and Implementation
- 10Power Supply Recommendations
- 11Layout
- 12Device and Documentation Support
- 13Mechanical, Packaging, and Orderable Information
8.3.7.2.1 Output Power Limit
The regulators have output peak current limits. The peak current limits are described in Electrical Charasteristics Table. If the load current is increased so that the current limit is triggered, the regulator continues to regulate to the limit current level (current peak regulation, peak on each switching cycle). The voltage may decrease if the load current is higher than the average output current. If the current regulation continues for 20 µs, the LP8752x-Q1 device sets the BUCKx_ILIM_INT bit (in INT_BUCKx register) and pulls the nINT pin low. The host processor can read BUCKx_ILIM_STAT bits (in BUCKx_STAT register) to see if the regulator is still in peak-current-regulation mode.
If the load is so high that the output voltage decreases below a 350-mV level, the LP8752x-Q1 device disables the regulator and sets the BUCKx_SC_INT bit (in INT_BUCKx register). In addition the BUCKx_STAT bit (in BUCKx_STAT register) is set to 0. The interrupt is cleared when the host processor writes 1 to BUCKx_SC_INT bit. The overload situation is shown in Figure 20.
Figure 20. Overload Situation