SLVAET3
October 2021
TPS8802
Trademarks
1
Introduction
2
System Architecture
2.1
Battery Voltage
2.2
VCC Supply
2.2.1
Connecting VCC to VBST
2.2.2
Connecting VCC to VBAT Through a Switch
2.3
MCU Supply
2.3.1
MCU Connected to VBAT
2.3.2
MCU Connected to MCU LDO
2.3.3
MCU with VCC Connected to VBAT Through a Switch
2.4
Photoelectric Smoke Sensor LED Supply
2.4.1
LED Connected to VBAT
2.4.2
LED Connected to PLDO
2.4.3
LED Connected to LEDLDO
2.5
Example Schematics
2.5.1
Smoke and CO Schematics
2.5.2
Smoke-Only Schematics
3
Current Consumption
3.1
Standby Current
3.1.1
TPS8802 Standby Current
3.1.2
Microcontroller Standby Current
3.2
Measurement Current
3.2.1
Smoke Measurement Current
3.2.2
CO Measurement Current
3.2.3
Battery Test Current
3.2.4
User Alarm Test Current
3.3
Other Current Consumption
3.3.1
Boost Charge Current
3.3.2
Initialization Current
4
System Power Calculation and Measurements
4.1
Power Calculation Spreadsheet
4.1.1
Power Consumption Overview Page
4.1.2
Detailed Calculation Pages
4.2
Power Consumption Measurements
4.2.1
Power Measurement Method
4.2.2
Smoke and CO System Measurements
4.2.3
Smoke-Only System Measurements
5
Summary
6
References
3.3
Other Current Consumption