ZHCSL07C September 2019 – August 2021 TPS8802
PRODUCTION DATA
- 1 特性
- 2 应用
- 3 说明
- 4 Revision History
- 5 Pin Configuration and Functions
- 6 Specifications
- 7 Typical Characteristics
-
8 Detailed Description
- 8.1 Overview
- 8.2 Functional Block Diagram
- 8.3
Feature Description
- 8.3.1 System Power-up
- 8.3.2 LDO Regulators
- 8.3.3 Photo Chamber AFE
- 8.3.4 LED Driver
- 8.3.5 Carbon Monoxide Sensor AFE
- 8.3.6 Boost Converter
- 8.3.7 Interconnect Driver
- 8.3.8 Piezoelectric Horn Driver
- 8.3.9 Battery Test
- 8.3.10 AMUX
- 8.3.11 Analog Bias Block and 8 MHz Oscillator
- 8.3.12 Interrupt Signal Alerts
- 8.4 Device Functional Modes
- 8.5 Programming
- 8.6
Register Maps
- 8.6.1 REVID Register (Offset = 0h) [reset = 0h]
- 8.6.2 STATUS1 Register (Offset = 1h) [reset = 0h]
- 8.6.3 STATUS2 Register (Offset = 2h) [reset = 0h]
- 8.6.4 MASK Register (Offset = 3h) [reset = 0h]
- 8.6.5 CONFIG1 Register (Offset = 4h) [reset = 20h]
- 8.6.6 CONFIG2 Register (Offset = 5h) [reset = 2h]
- 8.6.7 ENABLE1 Register (Offset = 6h) [reset = 10h]
- 8.6.8 ENABLE2 Register (Offset = 7h) [reset = 0h]
- 8.6.9 CONTROL Register (Offset = 8h) [reset = 0h]
- 8.6.10 SLPTMR1 Register (Offset = 9h) [reset = 0h]
- 8.6.11 SLPTMR2 Register (Offset = Ah) [reset = 0h]
- 8.6.12 GPIO_AMUX Register (Offset = Bh) [reset = 0h]
- 8.6.13 CO_BATTEST Register (Offset = Ch) [reset = 0h]
- 8.6.14 CO Register (Offset = Dh) [reset = 0h]
- 8.6.15 VBOOST Register (Offset = Eh) [reset = F2h]
- 8.6.16 LEDLDO Register (Offset = Fh) [reset = 0h]
- 8.6.17 PH_CTRL Register (Offset = 10h) [reset = 0h]
- 8.6.18 LED_DAC_A Register (Offset = 11h) [reset = 0h]
- 8.6.19 LED_DAC_B Register (Offset = 12h) [reset = 0h]
- 9 Application and Implementation
- 10Power Supply Recommendations
- 11Layout
- 12Device and Documentation Support
- 13Mechanical, Packaging, and Orderable Information
8.3.8.1 Three-Terminal Piezo
Figure 8-9 Three-Terminal Piezoelectric Horn Driver CircuitIn the three-terminal mode, the piezo silver and brass terminals connect directly to the HORNSL and HORNBR pins, and the feedback terminal connects through a resistor-capacitor network to the HORNFB pin. The driver is enabled and begins oscillating when the HORN_EN register bit and HBEN pin are set high. Adjust the value of the resistor connected to the piezo feedback terminal to tune the oscillation frequency. Trial and error is required to select this resistance. After the driver achieves resonant oscillation, the duty cycle of the HORNSL and HORNBR outputs can be adjusted using the HORN_THR bits to maximize the loudness. It is recommended to try each HORN_THR value and select the one that operates the horn closest to 50% duty cycle.