Timer Developer Guide#

About This Guide#

This guide explains the timer peripherals available on the Silicon Labs SiWx917 device. It helps you select and configure the most suitable timer for your application. Each timer serves a specific purpose — from high-performance operation in active modes to precise, ultra-low-power timing during sleep states.

Audience#

This guide is designed for developers and system designers who are implementing timing features on the SiWx917 device. It is especially relevant if you are building IoT devices, battery-powered systems, or embedded products that need precise timing and optimized energy usage.

Purpose#

This document helps you:

Choose the right timer for your SiWx917 application.
Configure timers for performance and energy efficiency.
Integrate timers with power management and wake systems.
Implement reliable, predictable timing across power states.

Scope#

The guide focuses exclusively on SiWx917 timer peripherals, including:

Selecting a timer depends on your application’s timing accuracy, energy budget, and reliability needs.


Application Type	Recommended Timer	Key Benefits
High-performance control	Configurable Timer (CT)	High-speed PWM, precise control, deterministic timing
Low-power scheduling	SYSRTC / ULP Timer	Continuous or ultra-low-power timing
Multi-timing operations	SYSRTC	Multiple timing groups, coordination across subsystems

Power State Compatibility#


Timer	PS4	PS2	PS1	PS0
CT	Full	Suspended	Suspended	Suspended
SYSRTC	Full	Full	Full	Full
ULP Timer	Full	Full	Wake Source	N/A

Quick Reference#


Property	CT	SYSRTC	ULP Timer
Clock Source	40–160 MHz (PLL)	32 kHz (RC/XTAL)	32 kHz–32 MHz
Counter Width	Dual 16-bit	32-bit shared	32-bit
Primary Use	PWM, waveform	Timekeeping	Sleep scheduling