diff --git a/components/esp8266/driver/pwm.c b/components/esp8266/driver/pwm.c
index 376aa756..73c3d0f8 100644
--- a/components/esp8266/driver/pwm.c
+++ b/components/esp8266/driver/pwm.c
@@ -514,7 +514,7 @@ static esp_err_t pwm_obj_free(void)
     return ESP_OK;
 }
 
-static esp_err_t pwm_obj_malloc(uint32_t channel_num)
+static esp_err_t pwm_obj_malloc(uint8_t channel_num)
 {
     pwm_obj = (pwm_obj_t *)heap_caps_malloc(sizeof(pwm_obj_t), MALLOC_CAP_8BIT);
 
@@ -539,7 +539,7 @@ static esp_err_t pwm_obj_malloc(uint32_t channel_num)
     return ESP_OK;
 }
 
-esp_err_t pwm_init(uint32_t period, uint32_t *duties, uint32_t channel_num, const uint32_t *pin_num)
+esp_err_t pwm_init(uint32_t period, uint32_t *duties, uint8_t channel_num, const uint32_t *pin_num)
 {
     PWM_CHECK(pwm_obj == NULL, "pwm has been initialized", ESP_FAIL);
     PWM_CHECK(channel_num <= MAX_PWM_CHANNEL, "Channel num out of range", ESP_ERR_INVALID_ARG);
diff --git a/components/esp8266/include/driver/pwm.h b/components/esp8266/include/driver/pwm.h
index cc1f643c..c457ba91 100644
--- a/components/esp8266/include/driver/pwm.h
+++ b/components/esp8266/include/driver/pwm.h
@@ -27,7 +27,7 @@ extern "C" {
   * @param  period PWM period, unit: us.
   *         e.g. For 1KHz PWM, period is 1000 us. Do not set the period below 20us.
   * @param  duties duty cycle of each channels.
-  * @param  pwm_channel_num PWM channel number, maximum is 8
+  * @param  channel_num PWM channel number, maximum is 8
   * @param  pin_num GPIO number of PWM channel
   * 
   * @return
@@ -35,7 +35,7 @@ extern "C" {
   *     - ESP_ERR_INVALID_ARG Parameter error
   *     - ESP_FAIL Init error
   */
-esp_err_t pwm_init(uint32_t period, uint32_t *duties, uint32_t pwm_channel_num, const uint32_t *pin_num);
+esp_err_t pwm_init(uint32_t period, uint32_t *duties, uint8_t channel_num, const uint32_t *pin_num);
 
 /**
   * @brief  PWM function uninstall
diff --git a/examples/peripherals/pwm/README.md b/examples/peripherals/pwm/README.md
index 91df1ad2..c073186b 100644
--- a/examples/peripherals/pwm/README.md
+++ b/examples/peripherals/pwm/README.md
@@ -47,7 +47,7 @@ I (220) gpio: GPIO[12]| InputEn: 0| OutputEn: 1| OpenDrain: 0| Pullup: 0| Pulldo
 I (225) gpio: GPIO[13]| InputEn: 0| OutputEn: 1| OpenDrain: 0| Pullup: 0| Pulldown: 0| Intr:0
 I (247) gpio: GPIO[14]| InputEn: 0| OutputEn: 1| OpenDrain: 0| Pullup: 0| Pulldown: 0| Intr:0
 I (251) gpio: GPIO[15]| InputEn: 0| OutputEn: 1| OpenDrain: 0| Pullup: 0| Pulldown: 0| Intr:0
-I (265) pwm: --- PWM v3.0
+I (265) pwm: --- PWM v3.2
 
 I (20276) main: PWM stop
 
diff --git a/examples/peripherals/pwm/main/pwm_example_main.c b/examples/peripherals/pwm/main/pwm_example_main.c
index 989b4648..e7f1df5d 100644
--- a/examples/peripherals/pwm/main/pwm_example_main.c
+++ b/examples/peripherals/pwm/main/pwm_example_main.c
@@ -30,8 +30,8 @@
 #define PWM_2_OUT_IO_NUM   14
 #define PWM_3_OUT_IO_NUM   15
 
-// PWM period 500us(2Khz), same as depth
-#define PWM_PERIOD    (500)
+// PWM period 1000us(1Khz), same as depth
+#define PWM_PERIOD    (1000)
 
 static const char *TAG = "pwm_example";
 
@@ -45,7 +45,7 @@ const uint32_t pin_num[4] = {
 
 // duties table, real_duty = duties[x]/PERIOD
 uint32_t duties[4] = {
-    250, 250, 250, 250,
+    500, 500, 500, 500,
 };
 
 // phase table, delay = (phase[x]/360)*PERIOD
diff --git a/examples/peripherals/pwm/wave.png b/examples/peripherals/pwm/wave.png
index a7ace1e4..7c52a98b 100644
Binary files a/examples/peripherals/pwm/wave.png and b/examples/peripherals/pwm/wave.png differ