11 files changed, 136 insertions, 10 deletions

diff --git a/docs/feature_rgb_matrix.md b/docs/feature_rgb_matrix.md
index fa06e46e4..cad7c50f1 100644
--- a/docs/feature_rgb_matrix.md
+++ b/docs/feature_rgb_matrix.md
@@ -21,6 +21,7 @@ You can use between 1 and 4 IS31FL3731 IC's. Do not specify `DRIVER_ADDR_<N>` de
 |----------|-------------|---------|
 | `ISSI_TIMEOUT` | (Optional) How long to wait for i2c messages, in milliseconds | 100 |
 | `ISSI_PERSISTENCE` | (Optional) Retry failed messages this many times | 0 |
+| `ISSI_3731_DEGHOST` | (Optional) Set this define to enable de-ghosting by halving Vcc during blanking time | |
 | `DRIVER_COUNT` | (Required) How many RGB driver IC's are present | |
 | `DRIVER_LED_TOTAL` | (Required) How many RGB lights are present across all drivers | |
 | `DRIVER_ADDR_1` | (Required) Address for the first RGB driver | |
@@ -85,6 +86,8 @@ You can use between 1 and 4 IS31FL3733 IC's. Do not specify `DRIVER_ADDR_<N>` de
 | `ISSI_TIMEOUT` | (Optional) How long to wait for i2c messages, in milliseconds | 100 |
 | `ISSI_PERSISTENCE` | (Optional) Retry failed messages this many times | 0 |
 | `ISSI_PWM_FREQUENCY` | (Optional) PWM Frequency Setting - IS31FL3733B only | 0 |
+| `ISSI_SWPULLUP` | (Optional) Set the value of the SWx lines on-chip de-ghosting resistors | PUR_0R (Disabled) |
+| `ISSI_CSPULLUP` | (Optional) Set the value of the CSx lines on-chip de-ghosting resistors | PUR_0R (Disabled) |
 | `DRIVER_COUNT` | (Required) How many RGB driver IC's are present | |
 | `DRIVER_LED_TOTAL` | (Required) How many RGB lights are present across all drivers | |
 | `DRIVER_ADDR_1` | (Required) Address for the first RGB driver | |
@@ -96,6 +99,18 @@ You can use between 1 and 4 IS31FL3733 IC's. Do not specify `DRIVER_ADDR_<N>` de
 | `DRIVER_SYNC_3` | (Optional) Sync configuration for the third RGB driver | 0 |
 | `DRIVER_SYNC_4` | (Optional) Sync configuration for the fourth RGB driver | 0 |
 
+The IS31FL3733 IC's have on-chip resistors that can be enabled to allow for de-ghosting of the RGB matrix. By default these resistors are not enabled (`ISSI_SWPULLUP`/`ISSI_CSPULLUP` are given the value of`PUR_0R`), the values that can be set to enable de-ghosting are as follows:
+
+| `ISSI_SWPULLUP/ISSI_CSPULLUP` | Description |
+|----------------------|-------------|
+| `PUR_0R` | (default) Do not use the on-chip resistors/enable de-ghosting |
+| `PUR_05KR` | The 0.5k Ohm resistor used during blanking period (t_NOL) |
+| `PUR_3KR` | The 3k Ohm resistor used at all times |
+| `PUR_4KR` | The 4k Ohm resistor used at all times |
+| `PUR_8KR` | The 8k Ohm resistor used at all times |
+| `PUR_16KR` | The 16k Ohm resistor used at all times |
+| `PUR_32KR` | The 32k Ohm resistor used during blanking period (t_NOL) |
+
 Here is an example using 2 drivers.
 
 ```c
@@ -156,11 +171,25 @@ Configure the hardware via your `config.h`:
 |----------|-------------|---------|
 | `ISSI_TIMEOUT` | (Optional) How long to wait for i2c messages, in milliseconds | 100 |
 | `ISSI_PERSISTENCE` | (Optional) Retry failed messages this many times | 0 |
+| `ISSI_SWPULLUP` | (Optional) Set the value of the SWx lines on-chip de-ghosting resistors | PUR_0R (Disabled) |
+| `ISSI_CSPULLUP` | (Optional) Set the value of the CSx lines on-chip de-ghosting resistors | PUR_0R (Disabled) |
 | `DRIVER_COUNT` | (Required) How many RGB driver IC's are present | |
 | `DRIVER_LED_TOTAL` | (Required) How many RGB lights are present across all drivers | |
 | `DRIVER_ADDR_1` | (Required) Address for the first RGB driver | |
 | `DRIVER_ADDR_2` | (Optional) Address for the second RGB driver | |
 
+The IS31FL3737 IC's have on-chip resistors that can be enabled to allow for de-ghosting of the RGB matrix. By default these resistors are not enabled (`ISSI_SWPULLUP`/`ISSI_CSPULLUP` are given the value of`PUR_0R`), the values that can be set to enable de-ghosting are as follows:
+
+| `ISSI_SWPULLUP/ISSI_CSPULLUP` | Description |
+|----------------------|-------------|
+| `PUR_0R` | (default) Do not use the on-chip resistors/enable de-ghosting |
+| `PUR_05KR` | The 0.5k Ohm resistor used during blanking period (t_NOL) |
+| `PUR_1KR` | The 1k Ohm resistor used during blanking period (t_NOL) |
+| `PUR_2KR` | The 2k Ohm resistor used during blanking period (t_NOL) |
+| `PUR_4KR` | The 4k Ohm resistor used during blanking period (t_NOL) |
+| `PUR_8KR` | The 8k Ohm resistor during blanking period (t_NOL) |
+| `PUR_16KR` | The 16k Ohm resistor during blanking period (t_NOL) |
+| `PUR_32KR` | The 32k Ohm resistor used during blanking period (t_NOL) |
 
 Here is an example using 2 drivers.
 
@@ -184,7 +213,7 @@ Here is an example using 2 drivers.
 ```
 !> Note the parentheses, this is so when `DRIVER_LED_TOTAL` is used in code and expanded, the values are added together before any additional math is applied to them. As an example, `rand() % (DRIVER_1_LED_TOTAL + DRIVER_2_LED_TOTAL)` will give very different results than `rand() % DRIVER_1_LED_TOTAL + DRIVER_2_LED_TOTAL`.
 
-Currently only 2 drivers are supported, but it would be trivial to support all 4 combinations. 
+Currently only 2 drivers are supported, but it would be trivial to support all 4 combinations.
 
 Define these arrays listing all the LEDs in your `<keyboard>.c`:
 
@@ -343,7 +372,7 @@ x = 224 / (NUMBER_OF_COLS - 1) * COL_POSITION
 y =  64 / (NUMBER_OF_ROWS - 1) * ROW_POSITION
 ```
 
-Where NUMBER_OF_COLS, NUMBER_OF_ROWS, COL_POSITION, & ROW_POSITION are all based on the physical layout of your keyboard, not the electrical layout. 
+Where NUMBER_OF_COLS, NUMBER_OF_ROWS, COL_POSITION, & ROW_POSITION are all based on the physical layout of your keyboard, not the electrical layout.
 
 As mentioned earlier, the center of the keyboard by default is expected to be `{ 112, 32 }`, but this can be changed if you want to more accurately calculate the LED's physical `{ x, y }` positions. Keyboard designers can implement `#define RGB_MATRIX_CENTER { 112, 32 }` in their config.h file with the new center point of the keyboard, or where they want it to be allowing more possibilities for the `{ x, y }` values. Do note that the maximum value for x or y is 255, and the recommended maximum is 224 as this gives animations runoff room before they reset.
 
@@ -386,7 +415,7 @@ All RGB keycodes are currently shared with the RGBLIGHT system:
 
 * `RGB_MODE_*` keycodes will generally work, but not all of the modes are currently mapped to the correct effects for the RGB Matrix system.
 
-`RGB_MODE_PLAIN`, `RGB_MODE_BREATHE`, `RGB_MODE_RAINBOW`, and `RGB_MATRIX_SWIRL` are the only ones that are mapped properly. The rest don't have a direct equivalent, and are not mapped. 
+`RGB_MODE_PLAIN`, `RGB_MODE_BREATHE`, `RGB_MODE_RAINBOW`, and `RGB_MATRIX_SWIRL` are the only ones that are mapped properly. The rest don't have a direct equivalent, and are not mapped.
 
 !> By default, if you have both the [RGB Light](feature_rgblight.md) and the RGB Matrix feature enabled, these keycodes will work for both features, at the same time. You can disable the keycode functionality by defining the `*_DISABLE_KEYCODES` option for the specific feature.
 
@@ -423,7 +452,7 @@ enum rgb_matrix_effects {
     RGB_MATRIX_JELLYBEAN_RAINDROPS, // Randomly changes a single key's hue and saturation
     RGB_MATRIX_HUE_BREATHING,       // Hue shifts up a slight ammount at the same time, then shifts back
     RGB_MATRIX_HUE_PENDULUM,        // Hue shifts up a slight ammount in a wave to the right, then back to the left
-    RGB_MATRIX_HUE_WAVE,            // Hue shifts up a slight ammount and then back down in a wave to the right 
+    RGB_MATRIX_HUE_WAVE,            // Hue shifts up a slight ammount and then back down in a wave to the right
     RGB_MATRIX_FRACTAL,             // Single hue fractal filled keys pulsing horizontally out to edges
 #if define(RGB_MATRIX_FRAMEBUFFER_EFFECTS)
     RGB_MATRIX_TYPING_HEATMAP,      // How hot is your WPM!
@@ -698,7 +727,7 @@ Where `28` is an unused index from `eeconfig.h`.
 
 ### Indicators :id=indicators
 
-If you want to set custom indicators, such as an LED for Caps Lock, or layer indication, you can use the `rgb_matrix_indicators_kb` or `rgb_matrix_indicators_user` function for that: 
+If you want to set custom indicators, such as an LED for Caps Lock, or layer indication, you can use the `rgb_matrix_indicators_kb` or `rgb_matrix_indicators_user` function for that:
 ```c
 void rgb_matrix_indicators_kb(void) {
     rgb_matrix_set_color(index, red, green, blue);
@@ -753,18 +782,18 @@ This example sets the modifiers to be a specific color based on the layer state.
 ```c
 void rgb_matrix_indicators_advanced_user(uint8_t led_min, uint8_t led_max) {
     HSV hsv = {0, 255, 255};
-    
+
     if (layer_state_is(layer_state, 2)) {
         hsv = {130, 255, 255};
     } else {
         hsv = {30, 255, 255};
     }
-    
+
     if (hsv.v > rgb_matrix_get_val()) {
         hsv.v = rgb_matrix_get_val();
     }
     RGB rgb = hsv_to_rgb(hsv);
-    
+
     for (uint8_t i = led_min; i <= led_max; i++) {
         if (HAS_FLAGS(g_led_config.flags[i], 0x01)) { // 0x01 == LED_FLAG_MODIFIER
             rgb_matrix_set_color(i, rgb.r, rgb.g, rgb.b);
@@ -773,7 +802,7 @@ void rgb_matrix_indicators_advanced_user(uint8_t led_min, uint8_t led_max) {
 }
 ```
 
-If you want to indicate a Host LED status (caps lock, num lock, etc), you can use something like this to light up the caps lock key: 
+If you want to indicate a Host LED status (caps lock, num lock, etc), you can use something like this to light up the caps lock key:
 
 ```c
 void rgb_matrix_indicators_advanced_user(uint8_t led_min, uint8_t led_max) {
diff --git a/drivers/led/issi/is31fl3731-simple.c b/drivers/led/issi/is31fl3731-simple.c
index d295772f5..9d28ea91d 100644
--- a/drivers/led/issi/is31fl3731-simple.c
+++ b/drivers/led/issi/is31fl3731-simple.c
@@ -1,6 +1,7 @@
 /* Copyright 2017 Jason Williams
  * Copyright 2018 Jack Humbert
  * Copyright 2019 Clueboard
+ * Copyright 2021 Doni Crosby
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -40,6 +41,9 @@
 
 #define ISSI_REG_PICTUREFRAME 0x01
 
+// Not defined in the datasheet -- See AN for IC
+#define ISSI_REG_GHOST_IMAGE_PREVENTION 0xC2  // Set bit 4 to enable de-ghosting
+
 #define ISSI_REG_SHUTDOWN 0x0A
 #define ISSI_REG_AUDIOSYNC 0x06
 
@@ -144,6 +148,9 @@ void IS31FL3731_init(uint8_t addr) {
 
     // enable software shutdown
     IS31FL3731_write_register(addr, ISSI_REG_SHUTDOWN, 0x00);
+#ifdef ISSI_3731_DEGHOST  // set to enable de-ghosting of the array
+    IS31FL3731_write_register(addr, ISSI_REG_GHOST_IMAGE_PREVENTION, 0x10);
+#endif
 
     // this delay was copied from other drivers, might not be needed
     wait_ms(10);
diff --git a/drivers/led/issi/is31fl3731.c b/drivers/led/issi/is31fl3731.c
index 110bdc1be..fbf24c30f 100644
--- a/drivers/led/issi/is31fl3731.c
+++ b/drivers/led/issi/is31fl3731.c
@@ -1,5 +1,6 @@
 /* Copyright 2017 Jason Williams
  * Copyright 2018 Jack Humbert
+ * Copyright 2021 Doni Crosby
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -39,6 +40,9 @@
 
 #define ISSI_REG_PICTUREFRAME 0x01
 
+// Not defined in the datasheet -- See AN for IC
+#define ISSI_REG_GHOST_IMAGE_PREVENTION 0xC2  // Set bit 4 to enable de-ghosting
+
 #define ISSI_REG_SHUTDOWN 0x0A
 #define ISSI_REG_AUDIOSYNC 0x06
 
@@ -132,6 +136,9 @@ void IS31FL3731_init(uint8_t addr) {
 
     // enable software shutdown
     IS31FL3731_write_register(addr, ISSI_REG_SHUTDOWN, 0x00);
+#ifdef ISSI_3731_DEGHOST  // set to enable de-ghosting of the array
+    IS31FL3731_write_register(addr, ISSI_REG_GHOST_IMAGE_PREVENTION, 0x10);
+#endif
 
     // this delay was copied from other drivers, might not be needed
     wait_ms(10);
diff --git a/drivers/led/issi/is31fl3733.c b/drivers/led/issi/is31fl3733.c
index 4ddd827ca..c64d03513 100644
--- a/drivers/led/issi/is31fl3733.c
+++ b/drivers/led/issi/is31fl3733.c
@@ -1,6 +1,7 @@
 /* Copyright 2017 Jason Williams
  * Copyright 2018 Jack Humbert
  * Copyright 2018 Yiancar
+ * Copyright 2021 Doni Crosby
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -58,6 +59,12 @@
 
 #ifndef ISSI_PWM_FREQUENCY
 #    define ISSI_PWM_FREQUENCY 0b000  // PFS - IS31FL3733B only
+#ifndef ISSI_SWPULLUP
+#    define ISSI_SWPULLUP PUR_0R
+#endif
+
+#ifndef ISSI_CSPULLUP
+#    define ISSI_CSPULLUP PUR_0R
 #endif
 
 // Transfer buffer for TWITransmitData()
@@ -158,6 +165,10 @@ void IS31FL3733_init(uint8_t addr, uint8_t sync) {
 
     // Select PG3
     IS31FL3733_write_register(addr, ISSI_COMMANDREGISTER, ISSI_PAGE_FUNCTION);
+    // Set de-ghost pull-up resistors (SWx)
+    IS31FL3733_write_register(addr, ISSI_REG_SWPULLUP, ISSI_SWPULLUP);
+    // Set de-ghost pull-down resistors (CSx)
+    IS31FL3733_write_register(addr, ISSI_REG_CSPULLUP, ISSI_CSPULLUP);
     // Set global current to maximum.
     IS31FL3733_write_register(addr, ISSI_REG_GLOBALCURRENT, 0xFF);
     // Disable software shutdown.
diff --git a/drivers/led/issi/is31fl3733.h b/drivers/led/issi/is31fl3733.h
index 64fd38eb1..daa226b41 100644
--- a/drivers/led/issi/is31fl3733.h
+++ b/drivers/led/issi/is31fl3733.h
@@ -1,6 +1,7 @@
 /* Copyright 2017 Jason Williams
  * Copyright 2018 Jack Humbert
  * Copyright 2018 Yiancar
+ * Copyright 2021 Doni Crosby
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -47,6 +48,14 @@ void IS31FL3733_set_led_control_register(uint8_t index, bool red, bool green, bo
 void IS31FL3733_update_pwm_buffers(uint8_t addr, uint8_t index);
 void IS31FL3733_update_led_control_registers(uint8_t addr, uint8_t index);
 
+#define PUR_0R 0x00    // No PUR resistor
+#define PUR_05KR 0x02  // 0.5k Ohm resistor in t_NOL
+#define PUR_3KR 0x03   // 3.0k Ohm resistor on all the time
+#define PUR_4KR 0x04   // 4.0k Ohm resistor on all the time
+#define PUR_8KR 0x05   // 8.0k Ohm resistor on all the time
+#define PUR_16KR 0x06  // 16k Ohm resistor on all the time
+#define PUR_32KR 0x07  // 32k Ohm resistor in t_NOL
+
 #define A_1 0x00
 #define A_2 0x01
 #define A_3 0x02
diff --git a/drivers/led/issi/is31fl3736.c b/drivers/led/issi/is31fl3736.c
index 7dece1b1e..dcaabba2e 100644
--- a/drivers/led/issi/is31fl3736.c
+++ b/drivers/led/issi/is31fl3736.c
@@ -1,4 +1,5 @@
 /* Copyright 2018 Jason Williams (Wilba)
+ * Copyright 2021 Doni Crosby
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -54,6 +55,14 @@
 #    define ISSI_PERSISTENCE 0
 #endif
 
+#ifndef ISSI_SWPULLUP
+#    define ISSI_SWPULLUP PUR_0R
+#endif
+
+#ifndef ISSI_CSPULLUP
+#    define ISSI_CSPULLUP PUR_0R
+#endif
+
 // Transfer buffer for TWITransmitData()
 uint8_t g_twi_transfer_buffer[20];
 
@@ -140,6 +149,10 @@ void IS31FL3736_init(uint8_t addr) {
 
     // Select PG3
     IS31FL3736_write_register(addr, ISSI_COMMANDREGISTER, ISSI_PAGE_FUNCTION);
+    // Set de-ghost pull-up resistors (SWx)
+    IS31FL3736_write_register(addr, ISSI_REG_SWPULLUP, ISSI_SWPULLUP);
+    // Set de-ghost pull-down resistors (CSx)
+    IS31FL3736_write_register(addr, ISSI_REG_CSPULLUP, ISSI_CSPULLUP);
     // Set global current to maximum.
     IS31FL3736_write_register(addr, ISSI_REG_GLOBALCURRENT, 0xFF);
     // Disable software shutdown.
diff --git a/drivers/led/issi/is31fl3736.h b/drivers/led/issi/is31fl3736.h
index c956c87f7..a30be9055 100644
--- a/drivers/led/issi/is31fl3736.h
+++ b/drivers/led/issi/is31fl3736.h
@@ -1,4 +1,5 @@
 /* Copyright 2018 Jason Williams (Wilba)
+ * Copyright 2021 Doni Crosby
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -60,6 +61,15 @@ void IS31FL3736_mono_set_led_control_register(uint8_t index, bool enabled);
 void IS31FL3736_update_pwm_buffers(uint8_t addr1, uint8_t addr2);
 void IS31FL3736_update_led_control_registers(uint8_t addr1, uint8_t addr2);
 
+#define PUR_0R 0x00    // No PUR resistor
+#define PUR_05KR 0x01  // 0.5k Ohm resistor
+#define PUR_1KR 0x02   // 1.0k Ohm resistor
+#define PUR_2KR 0x03   // 2.0k Ohm resistor
+#define PUR_4KR 0x04   // 4.0k Ohm resistor
+#define PUR_8KR 0x05   // 8.0k Ohm resistor
+#define PUR_16KR 0x06  // 16k Ohm resistor
+#define PUR_32KR 0x07  // 32k Ohm resistor
+
 #define A_1 0x00
 #define A_2 0x02
 #define A_3 0x04
diff --git a/drivers/led/issi/is31fl3737.c b/drivers/led/issi/is31fl3737.c
index 0bb4ddd42..62862e0d4 100644
--- a/drivers/led/issi/is31fl3737.c
+++ b/drivers/led/issi/is31fl3737.c
@@ -1,6 +1,7 @@
 /* Copyright 2017 Jason Williams
  * Copyright 2018 Jack Humbert
  * Copyright 2018 Yiancar
+ * Copyright 2021 Doni Crosby
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -56,6 +57,14 @@
 #    define ISSI_PERSISTENCE 0
 #endif
 
+#ifndef ISSI_SWPULLUP
+#    define ISSI_SWPULLUP PUR_0R
+#endif
+
+#ifndef ISSI_CSPULLUP
+#    define ISSI_CSPULLUP PUR_0R
+#endif
+
 // Transfer buffer for TWITransmitData()
 uint8_t g_twi_transfer_buffer[20];
 
@@ -143,6 +152,10 @@ void IS31FL3737_init(uint8_t addr) {
 
     // Select PG3
     IS31FL3737_write_register(addr, ISSI_COMMANDREGISTER, ISSI_PAGE_FUNCTION);
+    // Set de-ghost pull-up resistors (SWx)
+    IS31FL3737_write_register(addr, ISSI_REG_SWPULLUP, ISSI_SWPULLUP);
+    // Set de-ghost pull-down resistors (CSx)
+    IS31FL3737_write_register(addr, ISSI_REG_CSPULLUP, ISSI_CSPULLUP);
     // Set global current to maximum.
     IS31FL3737_write_register(addr, ISSI_REG_GLOBALCURRENT, 0xFF);
     // Disable software shutdown.
diff --git a/drivers/led/issi/is31fl3737.h b/drivers/led/issi/is31fl3737.h
index 06886e9c9..97917f1d4 100644
--- a/drivers/led/issi/is31fl3737.h
+++ b/drivers/led/issi/is31fl3737.h
@@ -1,6 +1,7 @@
 /* Copyright 2017 Jason Williams
  * Copyright 2018 Jack Humbert
  * Copyright 2018 Yiancar
+ * Copyright 2021 Doni Crosby
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -47,6 +48,15 @@ void IS31FL3737_set_led_control_register(uint8_t index, bool red, bool green, bo
 void IS31FL3737_update_pwm_buffers(uint8_t addr1, uint8_t addr2);
 void IS31FL3737_update_led_control_registers(uint8_t addr1, uint8_t addr2);
 
+#define PUR_0R 0x00    // No PUR resistor
+#define PUR_05KR 0x01  // 0.5k Ohm resistor in t_NOL
+#define PUR_1KR 0x02   // 1.0k Ohm resistor in t_NOL
+#define PUR_2KR 0x03   // 2.0k Ohm resistor in t_NOL
+#define PUR_4KR 0x04   // 4.0k Ohm resistor in t_NOL
+#define PUR_8KR 0x05   // 8.0k Ohm resistor in t_NOL
+#define PUR_16KR 0x06  // 16k Ohm resistor in t_NOL
+#define PUR_32KR 0x07  // 32k Ohm resistor in t_NOL
+
 #define A_1 0x00
 #define A_2 0x01
 #define A_3 0x02
diff --git a/drivers/led/issi/is31fl3741.c b/drivers/led/issi/is31fl3741.c
index 24a273514..5084f3b9f 100644
--- a/drivers/led/issi/is31fl3741.c
+++ b/drivers/led/issi/is31fl3741.c
@@ -61,6 +61,14 @@
 #    define ISSI_PERSISTENCE 0
 #endif
 
+#ifndef ISSI_SWPULLUP
+#    define ISSI_SWPULLUP PUR_32KR
+#endif
+
+#ifndef ISSI_CSPULLUP
+#    define ISSI_CSPULLUP PUR_32KR
+#endif
+
 #define ISSI_MAX_LEDS 351
 
 // Transfer buffer for TWITransmitData()
@@ -157,7 +165,7 @@ void IS31FL3741_init(uint8_t addr) {
     // Set Golbal Current Control Register
     IS31FL3741_write_register(addr, ISSI_REG_GLOBALCURRENT, 0xFF);
     // Set Pull up & Down for SWx CSy
-    IS31FL3741_write_register(addr, ISSI_REG_PULLDOWNUP, 0x77);
+    IS31FL3741_write_register(addr, ISSI_REG_PULLDOWNUP, ((ISSI_CSPULLUP << 4) | ISSI_SWPULLUP));
 
     // IS31FL3741_update_led_scaling_registers(addr, 0xFF, 0xFF, 0xFF);
 
diff --git a/drivers/led/issi/is31fl3741.h b/drivers/led/issi/is31fl3741.h
index 163a03523..563022b9b 100644
--- a/drivers/led/issi/is31fl3741.h
+++ b/drivers/led/issi/is31fl3741.h
@@ -51,6 +51,15 @@ void IS31FL3741_set_scaling_registers(const is31_led *pled, uint8_t red, uint8_t
 
 void IS31FL3741_set_pwm_buffer(const is31_led *pled, uint8_t red, uint8_t green, uint8_t blue);
 
+#define PUR_0R 0x00    // No PUR resistor
+#define PUR_05KR 0x01  // 0.5k Ohm resistor
+#define PUR_1KR 0x02   // 1.0k Ohm resistor
+#define PUR_2KR 0x03   // 2.0k Ohm resistor
+#define PUR_4KR 0x04   // 4.0k Ohm resistor
+#define PUR_8KR 0x05   // 8.0k Ohm resistor
+#define PUR_16KR 0x06  // 16k Ohm resistor
+#define PUR_32KR 0x07  // 32k Ohm resistor
+
 #define CS1_SW1 0x00
 #define CS2_SW1 0x01
 #define CS3_SW1 0x02