Overview
The TPS8802DCPR, produced by Texas Instruments, is a highly integrated Analog Front End (AFE) designed specifically for residential smoke and carbon monoxide (CO) alarm systems. This device combines all the necessary regulators, amplifiers, and drivers to support dual-wave photoelectric smoke detection and CO detection. It is optimized for low power consumption, making it ideal for battery-powered smoke alarms with a 10-year battery life from a single lithium primary battery.
The TPS8802DCPR features a wide input voltage range, ultra-low power consumption, and advanced power-saving features, ensuring continuous operation even during power outages or battery disconnection. Its high flexibility and precision make it a reliable choice for critical safety applications.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| Power Up Threshold (VPWRUP) | 1.2 | 1.55 | 2.0 | V |
| Power Down Threshold (VPWRDOWN) | 0.932 | 1.15 | 2.0 | V |
| Standby Supply Current (ISTANDBY) | 3.8 | 4.4 | - | µA (VCC=3V, VMCU=1.8V) |
| Standby Supply Current (ISTANDBY) | 7.7 | 9.1 | - | µA (VCC=9V, VMCU=3.3V) |
| MCU LDO Output Voltage (VMCULDO) | - | - | - | V (IMCULDO < 30 mA, VCC > 2.2 V) |
| MCU LDO Power Up Time (TMCULDO, PWR) | 600 | 1100 | - | µs (CMCULDO = 1µF) |
| Boost Converter Feedback Voltage (VBST) | - | - | - | V (IBST < 20 mA, 2.0 V < VBAT < 13.5 V) |
| Junction-to-Ambient Thermal Resistance (RθJA) | - | 29.3 | - | °C/W |
Key Features
- Photo Chamber AFE: Dual 8-bit programmable current LED drivers with temperature compensation of LED current, ultra-low offset op-amp for photodiodes, and a programmable and bypassable gain stage.
- Carbon Monoxide Sensor AFE: Ultra-low offset gain stage with programmable gain and reference.
- Horn Driver: Self-resonant driver for three-terminal piezos and PWM support for voice on two-terminal piezos.
- Power Management: Programmable LDO for external microcontroller, boost converter for horn and interconnect, and ultra-low power consumption.
- Interconnection Bus: For multi-alarm communication.
- I2C Serial Interface: For communication with external devices.
- Programmable Battery Test Load: For battery life testing.
Applications
- Smoke and CO Alarms: The TPS8802DCPR is specifically designed for residential smoke and carbon monoxide alarm systems, ensuring reliable and accurate detection.
- Battery Backup Smoke Alarms: Supports seamless operation during power outages or battery disconnection.
Q & A
- What is the primary function of the TPS8802DCPR?
The TPS8802DCPR is an Analog Front End (AFE) designed for residential smoke and carbon monoxide alarm systems.
- What are the key features of the Photo Chamber AFE in the TPS8802DCPR?
The Photo Chamber AFE includes dual 8-bit programmable current LED drivers, temperature compensation of LED current, an ultra-low offset op-amp for photodiodes, and a programmable and bypassable gain stage.
- How does the TPS8802DCPR manage power for the horn driver?
The device includes a self-resonant driver for three-terminal piezos and PWM support for voice on two-terminal piezos.
- What is the significance of the I2C serial interface in the TPS8802DCPR?
The I2C serial interface allows for communication with external devices, enabling configuration and data exchange.
- How does the TPS8802DCPR support multi-alarm communication?
The device features an interconnection bus for multi-alarm communication, enabling multiple smoke alarms to communicate with each other.
- What are the power consumption characteristics of the TPS8802DCPR?
The device is designed for ultra-low power consumption, supporting a 10-year battery life from a single lithium primary battery.
- What are the thermal characteristics of the TPS8802DCPR?
The device has a junction-to-ambient thermal resistance (RθJA) of 29.3°C/W and other specified thermal metrics to ensure reliable operation.
- How does the TPS8802DCPR handle battery backup during power outages?
The device supports battery backup smoke alarms, ensuring continuous operation even when the mains supply drops or the battery is disconnected.
- What is the role of the programmable LDO in the TPS8802DCPR?
The programmable LDO provides a regulated voltage supply for an external microcontroller and internal IO buffers.
- Can the TPS8802DCPR be used in safety-critical applications?
Yes, the TPS8802DCPR is designed for safety-critical applications such as residential smoke and CO alarm systems, ensuring high reliability and precision.
