diff --git a/src/laser_diode/laser_diode.rs b/src/laser_diode/laser_diode.rs
index 40954b6..5c4e7cb 100644
--- a/src/laser_diode/laser_diode.rs
+++ b/src/laser_diode/laser_diode.rs
@@ -2,7 +2,8 @@ use miniconf::Miniconf;
 use stm32f4xx_hal::pac::ADC2;
 use crate::laser_diode::ld_ctrl::LdCtrl;
 use crate::laser_diode::ld_pwr_exc_protector::{LdPwrExcProtector, self};
-use core::{marker::PhantomData, f64::NAN};
+use crate::laser_diode::pd_mon;
+use core::marker::PhantomData;
 
 use uom::si::{
     electric_current::milliampere,
@@ -43,7 +44,8 @@ impl Settings{
 pub struct Settings {
     ld_drive_current: ElectricCurrent,
     ld_drive_current_limit: ElectricCurrent,
-    pd_i_to_out_pwr: IToPowerUnit,
+    #[miniconf(defer)]
+    pd_responsitivity: pd_mon::Parameters,
 }
 
 impl Default for Settings {
@@ -51,7 +53,7 @@ impl Default for Settings {
         Self {
             ld_drive_current: ElectricCurrent::new::<milliampere>(0.0),
             ld_drive_current_limit: ElectricCurrent::new::<milliampere>(0.0),
-            pd_i_to_out_pwr: IToPowerUnit {dimension: PhantomData, units: PhantomData, value: NAN}
+            pd_responsitivity: pd_mon::Parameters::default(),
         }
     }
 }
@@ -125,16 +127,17 @@ impl LdDrive{
         LdPwrExcProtector::clear_alarm_status();
     }
 
+    pub fn set_pd_responsitivity(&mut self, responsitivity: pd_mon::ResponsitivityUnit){
+        self.settings.pd_responsitivity.responsitivity = responsitivity;
+    }
+
     pub fn set_ld_power_limit(&mut self, pwr_limit: Power){
-        // LdPwrExcProtector::set_trigger_threshold_v(convert pwr_limit to raw adc code)
-        unimplemented!()
+        LdPwrExcProtector::set_trigger_threshold_v(self.settings.pd_responsitivity
+            .get_ld_i_from_ld_pwr(pwr_limit) / Settings::PD_MON_TRANSCONDUCTANCE
+        );
     }
 
     pub fn set_pd_i_limit(&mut self, i: ElectricCurrent){
         LdPwrExcProtector::set_trigger_threshold_v(i / Settings::PD_MON_TRANSCONDUCTANCE);
     }
-
-    pub fn set_pd_v_limit(&mut self, v: ElectricPotential){
-        LdPwrExcProtector::set_trigger_threshold_v(v);
-    }
 }
diff --git a/src/laser_diode/pd_mon.rs b/src/laser_diode/pd_mon.rs
index fe69219..e09cf8d 100644
--- a/src/laser_diode/pd_mon.rs
+++ b/src/laser_diode/pd_mon.rs
@@ -12,19 +12,22 @@ use miniconf::Miniconf;
 // Ampere / Watt
 pub type ResponsitivityUnit = Quantity<ISQ<N2, N1, P3, P1, Z0, Z0, Z0>, SI<f64>, f64>; 
 
-/// Steinhart-Hart equation Photodiode
 #[derive(Clone, Debug, PartialEq, Miniconf)]
 pub struct Parameters {
-    /// Responsitivity
     pub responsitivity: ResponsitivityUnit,
     pub i_dark: ElectricCurrent,
 }
 
 impl Parameters {
-    pub fn get_ld_output_power(&self, i: ElectricCurrent) -> Power {
+    pub fn get_ld_pwr_from_ld_i(&self, i: ElectricCurrent) -> Power {
         let ld_power = (i - self.i_dark) / self.responsitivity;
         ld_power
     }
+
+    pub fn get_ld_i_from_ld_pwr(&self, pwr: Power) -> ElectricCurrent {
+        let ld_i = pwr * self.responsitivity + self.i_dark;
+        ld_i
+    }
 }
 
 impl Default for Parameters {