Check the listing for details. Adjustable PWM Pulse Frequency Duty Cycle Square Wave Signal Generator Module K9. Condition: New. Listed at 1.85 USD. Adjustable PWM Pulse Frequency Duty Cycle Square Wave Signal Generator Module K9Product Image: Product Description: 1. Item 1 Highlights: Two independent PWM generators can set the frequency, duty cycle; The wide frequency range, high accuracy; Can serial communication. First, the module description： Frequency is divided into three ranges: XXX (no decimal point): the smallest unit is 1Hz, the range 1Hz ~ 999Hz; XX.X (decimal point in ten): The minimum unit is 0.1Khz; the range of 0.1KHz ~ 99.9KHz X.X.X. (there are three decimal point): the smallest unit is 1Khz; the range 1KHz ~ 150KHz Frequency display example: "100" indicates that the PWM output pulse of 100Hz; "54.1" indicates that the PWM output pulse of 54.1KHz; "1.2.4." Indicates that the PWM pulse output 124KHz Duty Cycle in the range: 0 to 100; Three frequencies duty cycle is the same, all the parameters non-volatile. Second, the module parameters: Working voltage: 5--30V, support micro USB 5.0V power supply; Frequency range: 1Hz ~ 150KHz; The frequency accuracy: ± 2%; Output Current: