diff --git a/boards/ikea-tradfri/include/board.h b/boards/ikea-tradfri/include/board.h
index 6ca31bb52f..108f827236 100644
--- a/boards/ikea-tradfri/include/board.h
+++ b/boards/ikea-tradfri/include/board.h
@@ -31,10 +31,14 @@ extern "C" {
 /**
  * @name    Xtimer configuration
  *
- * The timer runs at 250 KHz to increase accuracy.
+ * The timer runs at 250 kHz to increase accuracy or 32768 Hz for LETIMER.
  * @{
  */
+#ifdef EFM32_USE_LETIMER
+#define XTIMER_HZ           (32768UL)
+#else
 #define XTIMER_HZ           (250000UL)
+#endif
 #define XTIMER_WIDTH        (16)
 /** @} */
 
diff --git a/boards/ikea-tradfri/include/periph_conf.h b/boards/ikea-tradfri/include/periph_conf.h
index 2e8b22c794..77e72a3f9c 100644
--- a/boards/ikea-tradfri/include/periph_conf.h
+++ b/boards/ikea-tradfri/include/periph_conf.h
@@ -48,7 +48,6 @@ extern "C" {
 #endif
 /** @} */
 
-
 /**
  * @name    RTT configuration
  * @{
@@ -82,25 +81,41 @@ static const spi_dev_t spi_config[] = {
 /**
  * @name    Timer configuration
  *
- * The implementation uses two timers in cascade mode.
+ * The implementation can use one low-energy timer
+ * or two regular timers in cascade mode.
  * @{
  */
+#if EFM32_USE_LETIMER
 static const timer_conf_t timer_config[] = {
     {
-        {
+        .timer = {
+            .dev = LETIMER0,
+            .cmu = cmuClock_LETIMER0
+        },
+        .irq = LETIMER0_IRQn
+    }
+};
+#define TIMER_0_ISR         isr_letimer0
+
+#else
+static const timer_conf_t timer_config[] = {
+    {
+        .prescaler = {
             .dev = TIMER0,
             .cmu = cmuClock_TIMER0
         },
-        {
+        .timer = {
             .dev = TIMER1,
             .cmu = cmuClock_TIMER1
         },
         .irq = TIMER1_IRQn
     }
 };
+#define TIMER_0_ISR         isr_timer1
+
+#endif /* EFM32_USE_LETIMER */
 
 #define TIMER_NUMOF         ARRAY_SIZE(timer_config)
-#define TIMER_0_ISR         isr_timer1
 /** @} */
 
 /**
diff --git a/boards/slstk3401a/include/board.h b/boards/slstk3401a/include/board.h
index 645149e122..40a9157694 100644
--- a/boards/slstk3401a/include/board.h
+++ b/boards/slstk3401a/include/board.h
@@ -32,10 +32,14 @@ extern "C" {
 /**
  * @name    Xtimer configuration
  *
- * The timer runs at 250 KHz to increase accuracy.
+ * The timer runs at 250 KHz to increase accuracy or 32768 Hz for LETIMER.
  * @{
  */
+#ifdef EFM32_USE_LETIMER
+#define XTIMER_HZ           (32768UL)
+#else
 #define XTIMER_HZ           (250000UL)
+#endif
 #define XTIMER_WIDTH        (16)
 /** @} */
 
diff --git a/boards/slstk3401a/include/periph_conf.h b/boards/slstk3401a/include/periph_conf.h
index 77201b0b7f..2a3ad6ba5f 100644
--- a/boards/slstk3401a/include/periph_conf.h
+++ b/boards/slstk3401a/include/periph_conf.h
@@ -141,25 +141,41 @@ static const spi_dev_t spi_config[] = {
 /**
  * @name    Timer configuration
  *
- * The implementation uses two timers in cascade mode.
+ * The implementation can use one low-energy timer
+ * or two regular timers in cascade mode.
  * @{
  */
+#if EFM32_USE_LETIMER
 static const timer_conf_t timer_config[] = {
     {
-        {
+        .timer = {
+            .dev = LETIMER0,
+            .cmu = cmuClock_LETIMER0
+        },
+        .irq = LETIMER0_IRQn
+    }
+};
+#define TIMER_0_ISR         isr_letimer0
+
+#else
+static const timer_conf_t timer_config[] = {
+    {
+        .prescaler = {
             .dev = TIMER0,
             .cmu = cmuClock_TIMER0
         },
-        {
+        .timer = {
             .dev = TIMER1,
             .cmu = cmuClock_TIMER1
         },
         .irq = TIMER1_IRQn
     }
 };
+#define TIMER_0_ISR         isr_timer1
+
+#endif /* EFM32_USE_LETIMER */
 
 #define TIMER_NUMOF         ARRAY_SIZE(timer_config)
-#define TIMER_0_ISR         isr_timer1
 /** @} */
 
 /**
diff --git a/boards/slstk3402a/include/board.h b/boards/slstk3402a/include/board.h
index 5ebff1cb2d..b4149c1f00 100644
--- a/boards/slstk3402a/include/board.h
+++ b/boards/slstk3402a/include/board.h
@@ -33,8 +33,13 @@ extern "C" {
  * @name    Xtimer configuration
  * @{
  */
+#ifdef EFM32_USE_LETIMER
+#define XTIMER_HZ           (32768UL)
+#define XTIMER_WIDTH        (16)
+#else
 #define XTIMER_HZ           (1000000UL)
 #define XTIMER_WIDTH        (32)
+#endif
 /** @} */
 
 /**
diff --git a/boards/slstk3402a/include/periph_conf.h b/boards/slstk3402a/include/periph_conf.h
index a93391a9f8..dfefe0bd5c 100644
--- a/boards/slstk3402a/include/periph_conf.h
+++ b/boards/slstk3402a/include/periph_conf.h
@@ -132,25 +132,41 @@ static const spi_dev_t spi_config[] = {
 /**
  * @name    Timer configuration
  *
- * The implementation uses two timers in cascade mode.
+ * The implementation can use one low-energy timer
+ * or two regular timers in cascade mode.
  * @{
  */
+#if EFM32_USE_LETIMER
 static const timer_conf_t timer_config[] = {
     {
-        {
+        .timer = {
+            .dev = LETIMER0,
+            .cmu = cmuClock_LETIMER0
+        },
+        .irq = LETIMER0_IRQn
+    }
+};
+#define TIMER_0_ISR         isr_letimer0
+
+#else
+static const timer_conf_t timer_config[] = {
+    {
+        .prescaler = {
             .dev = WTIMER0,
             .cmu = cmuClock_WTIMER0
         },
-        {
+        .timer = {
             .dev = WTIMER1,
             .cmu = cmuClock_WTIMER1
         },
         .irq = WTIMER1_IRQn
     }
 };
+#define TIMER_0_ISR         isr_wtimer1
+
+#endif /* EFM32_USE_LETIMER */
 
 #define TIMER_NUMOF         ARRAY_SIZE(timer_config)
-#define TIMER_0_ISR         isr_wtimer1
 /** @} */
 
 /**
diff --git a/boards/sltb001a/include/board.h b/boards/sltb001a/include/board.h
index dc59748dbc..1291ca66e9 100644
--- a/boards/sltb001a/include/board.h
+++ b/boards/sltb001a/include/board.h
@@ -32,11 +32,16 @@ extern "C" {
 /**
  * @name    Xtimer configuration
  *
- * The timer runs at 250 KHz to increase accuracy.
+ * The timer runs at 250 KHz to increase accuracy or 32768 Hz for LETIMER.
  * @{
  */
+#ifdef EFM32_USE_LETIMER
+#define XTIMER_HZ           (32768UL)
+#define XTIMER_WIDTH        (16)
+#else
 #define XTIMER_HZ           (250000UL)
 #define XTIMER_WIDTH        (16)
+#endif
 /** @} */
 
 /**
diff --git a/boards/sltb001a/include/periph_conf.h b/boards/sltb001a/include/periph_conf.h
index f43a84b353..ddc13e9645 100644
--- a/boards/sltb001a/include/periph_conf.h
+++ b/boards/sltb001a/include/periph_conf.h
@@ -141,25 +141,41 @@ static const spi_dev_t spi_config[] = {
 /**
  * @name    Timer configuration
  *
- * The implementation uses two timers in cascade mode.
+ * The implementation can use one low-energy timer
+ * or two regular timers in cascade mode.
  * @{
  */
+#if EFM32_USE_LETIMER
 static const timer_conf_t timer_config[] = {
     {
-        {
+        .timer = {
+            .dev = LETIMER0,
+            .cmu = cmuClock_LETIMER0
+        },
+        .irq = LETIMER0_IRQn
+    }
+};
+#define TIMER_0_ISR         isr_letimer0
+
+#else
+static const timer_conf_t timer_config[] = {
+    {
+        .prescaler = {
             .dev = TIMER0,
             .cmu = cmuClock_TIMER0
         },
-        {
+        .timer = {
             .dev = TIMER1,
             .cmu = cmuClock_TIMER1
         },
         .irq = TIMER1_IRQn
     }
 };
+#define TIMER_0_ISR         isr_timer1
+
+#endif /* EFM32_USE_LETIMER */
 
 #define TIMER_NUMOF         ARRAY_SIZE(timer_config)
-#define TIMER_0_ISR         isr_timer1
 /** @} */
 
 /**
diff --git a/boards/stk3600/include/board.h b/boards/stk3600/include/board.h
index e692bd8dca..52e0869e08 100644
--- a/boards/stk3600/include/board.h
+++ b/boards/stk3600/include/board.h
@@ -32,11 +32,16 @@ extern "C" {
 /**
  * @name    Xtimer configuration
  *
- * The timer runs at 250 KHz to increase accuracy.
+ * The timer runs at 250 KHz to increase accuracy or 32768 Hz for LETIMER.
  * @{
  */
+#ifdef EFM32_USE_LETIMER
+#define XTIMER_HZ           (32768UL)
+#define XTIMER_WIDTH        (16)
+#else
 #define XTIMER_HZ           (250000UL)
 #define XTIMER_WIDTH        (16)
+#endif
 /** @} */
 
 /**
diff --git a/boards/stk3600/include/periph_conf.h b/boards/stk3600/include/periph_conf.h
index 9d6e3a4e18..bbef6a9327 100644
--- a/boards/stk3600/include/periph_conf.h
+++ b/boards/stk3600/include/periph_conf.h
@@ -155,7 +155,6 @@ static const pwm_conf_t pwm_config[] = {
 #define PWM_NUMOF           ARRAY_SIZE(pwm_channel_config)
 /** @} */
 
-
 /**
  * @name    RTT configuration
  * @{
@@ -196,25 +195,41 @@ static const spi_dev_t spi_config[] = {
 /**
  * @name    Timer configuration
  *
- * The implementation uses two timers in cascade mode.
+ * The implementation can use one low-energy timer
+ * or two regular timers in cascade mode.
  * @{
  */
+#if EFM32_USE_LETIMER
 static const timer_conf_t timer_config[] = {
     {
-        {
+        .timer = {
+            .dev = LETIMER0,
+            .cmu = cmuClock_LETIMER0
+        },
+        .irq = LETIMER0_IRQn
+    }
+};
+#define TIMER_0_ISR         isr_letimer0
+
+#else
+static const timer_conf_t timer_config[] = {
+    {
+        .prescaler = {
             .dev = TIMER0,
             .cmu = cmuClock_TIMER0
         },
-        {
+        .timer = {
             .dev = TIMER1,
             .cmu = cmuClock_TIMER1
         },
         .irq = TIMER1_IRQn
     }
 };
+#define TIMER_0_ISR         isr_timer1
+
+#endif /* EFM32_USE_LETIMER */
 
 #define TIMER_NUMOF         ARRAY_SIZE(timer_config)
-#define TIMER_0_ISR         isr_timer1
 /** @} */
 
 /**
diff --git a/boards/stk3700/include/board.h b/boards/stk3700/include/board.h
index 6d79312310..973c6b2399 100644
--- a/boards/stk3700/include/board.h
+++ b/boards/stk3700/include/board.h
@@ -32,11 +32,16 @@ extern "C" {
 /**
  * @name    Xtimer configuration
  *
- * The timer runs at 250 KHz to increase accuracy.
+ * The timer runs at 250 KHz to increase accuracy or 32768 Hz for LETIMER.
  * @{
  */
+#ifdef EFM32_USE_LETIMER
+#define XTIMER_HZ           (32768UL)
+#define XTIMER_WIDTH        (16)
+#else
 #define XTIMER_HZ           (250000UL)
 #define XTIMER_WIDTH        (16)
+#endif
 /** @} */
 
 /**
diff --git a/boards/stk3700/include/periph_conf.h b/boards/stk3700/include/periph_conf.h
index ee54dec572..01829e99a9 100644
--- a/boards/stk3700/include/periph_conf.h
+++ b/boards/stk3700/include/periph_conf.h
@@ -155,7 +155,6 @@ static const pwm_conf_t pwm_config[] = {
 #define PWM_NUMOF           ARRAY_SIZE(pwm_channel_config)
 /** @} */
 
-
 /**
  * @name    RTT configuration
  * @{
@@ -196,25 +195,41 @@ static const spi_dev_t spi_config[] = {
 /**
  * @name    Timer configuration
  *
- * The implementation uses two timers in cascade mode.
+ * The implementation can use one low-energy timer
+ * or two regular timers in cascade mode.
  * @{
  */
+#if EFM32_USE_LETIMER
 static const timer_conf_t timer_config[] = {
     {
-        {
+        .timer = {
+            .dev = LETIMER0,
+            .cmu = cmuClock_LETIMER0
+        },
+        .irq = LETIMER0_IRQn
+    }
+};
+#define TIMER_0_ISR         isr_letimer0
+
+#else
+static const timer_conf_t timer_config[] = {
+    {
+        .prescaler = {
             .dev = TIMER0,
             .cmu = cmuClock_TIMER0
         },
-        {
+        .timer = {
             .dev = TIMER1,
             .cmu = cmuClock_TIMER1
         },
         .irq = TIMER1_IRQn
     }
 };
+#define TIMER_0_ISR         isr_timer1
+
+#endif /* EFM32_USE_LETIMER */
 
 #define TIMER_NUMOF         ARRAY_SIZE(timer_config)
-#define TIMER_0_ISR         isr_timer1
 /** @} */
 
 /**
diff --git a/cpu/efm32/include/periph_cpu.h b/cpu/efm32/include/periph_cpu.h
index fd6450ec98..6ef3507a33 100644
--- a/cpu/efm32/include/periph_cpu.h
+++ b/cpu/efm32/include/periph_cpu.h
@@ -348,17 +348,37 @@ typedef struct {
  * @{
  */
 typedef struct {
-    TIMER_TypeDef *dev;     /**< Timer device used */
+    void *dev;              /**< TIMER_TypeDef or LETIMER_TypeDef device used */
     CMU_Clock_TypeDef cmu;  /**< the device CMU channel */
 } timer_dev_t;
 
 typedef struct {
-    timer_dev_t prescaler;  /**< the lower numbered neighboring timer */
+    timer_dev_t prescaler;  /**< the lower neighboring timer (not initialized for LETIMER) */
     timer_dev_t timer;      /**< the higher numbered timer */
     IRQn_Type irq;          /**< number of the higher timer IRQ channel */
 } timer_conf_t;
 /** @} */
 
+
+/**
+ * @brief   The implementation can use one LETIMER or two regular timers cascaded
+ */
+#ifndef EFM32_USE_LETIMER
+#define EFM32_USE_LETIMER   0
+#endif
+
+#ifdef EFM32_USE_LETIMER
+/**
+ * @brief   This timer implementation has two available channels
+ */
+#define TIMER_CHANNEL_NUMOF     (2)
+#else
+/**
+ * @brief   This timer implementation has three available channels
+ */
+#define TIMER_CHANNEL_NUMOF     (3)
+#endif
+
 /**
  * @brief   UART device configuration.
  */
diff --git a/cpu/efm32/periph/timer.c b/cpu/efm32/periph/timer.c
index 8d92d2caed..ff291340f9 100644
--- a/cpu/efm32/periph/timer.c
+++ b/cpu/efm32/periph/timer.c
@@ -16,22 +16,31 @@
  *
  * @author      Hauke Petersen <hauke.petersen@fu-berlin.de>
  * @author      Bas Stottelaar <basstottelaar@gmail.com>
+ * @author      Thomas Stilwell <stilwellt@openlabs.co>
  * @}
  */
 
 #include "cpu.h"
-
+#include "log.h"
+#include "assert.h"
 #include "periph/timer.h"
 #include "periph_conf.h"
+#include "pm_layered.h"
 
 #include "em_cmu.h"
 #include "em_timer.h"
 #include "em_timer_utils.h"
+#include "em_letimer.h"
 
 /**
- * @brief   This timer implementation has three available channels
+ * @brief   These power modes will be blocked while the timer is running
  */
-#define CC_CHANNELS      (3U)
+#ifndef EFM32_TIMER_PM_BLOCKER
+#define EFM32_TIMER_PM_BLOCKER      1
+#endif
+#ifndef EFM32_LETIMER_PM_BLOCKER
+#define EFM32_LETIMER_PM_BLOCKER    0
+#endif
 
 /**
  * @brief   Timer state memory
@@ -47,24 +56,48 @@ static inline bool _is_wtimer(timer_t dev)
     return ((uint32_t) timer_config[dev].timer.dev) >= WTIMER0_BASE;
 #else
     (void) dev;
-
     return false;
 #endif
 }
 
-int timer_init(tim_t dev, unsigned long freq, timer_cb_t callback, void *arg)
+/**
+ * @brief   Check whether dev is using a LETIMER device
+ */
+static inline bool _is_letimer(timer_t dev)
+{
+#if defined(LETIMER_COUNT) && LETIMER_COUNT > 0
+    return ((uint32_t) timer_config[dev].timer.dev) == LETIMER0_BASE;
+#else
+    (void) dev;
+    return false;
+#endif
+}
+
+static void _letimer_init(tim_t dev, unsigned long freq)
+{
+    (void) freq;
+    assert(freq == 32768);
+
+    LETIMER_TypeDef *tim = timer_config[dev].timer.dev;
+
+    /* enable clocks */
+    CMU_ClockEnable(timer_config[dev].timer.cmu, true);
+    CMU_ClockEnable(cmuClock_CORELE, true);
+
+    /* disable and clear interrupts */
+    LETIMER_IntDisable(tim, LETIMER_IEN_COMP0 | LETIMER_IEN_COMP1);
+    LETIMER_IntClear(tim, LETIMER_IFC_COMP0 | LETIMER_IFC_COMP1);
+
+    /* initialize timer without starting it yet */
+    LETIMER_Init_TypeDef letimerInit = LETIMER_INIT_DEFAULT;
+    letimerInit.enable = false;
+    LETIMER_Init(tim, &letimerInit);
+}
+
+static void _timer_init(tim_t dev, unsigned long freq)
 {
     TIMER_TypeDef *pre, *tim;
 
-    /* test if given timer device is valid */
-    if (dev >= TIMER_NUMOF) {
-        return -1;
-    }
-
-    /* save callback */
-    isr_ctx[dev].cb = callback;
-    isr_ctx[dev].arg = arg;
-
     /* get timers */
     pre = timer_config[dev].prescaler.dev;
     tim = timer_config[dev].timer.dev;
@@ -78,9 +111,9 @@ int timer_init(tim_t dev, unsigned long freq, timer_cb_t callback, void *arg)
     TIMER_Init_TypeDef init_pre = TIMER_INIT_DEFAULT;
     TIMER_Init_TypeDef init_tim = TIMER_INIT_DEFAULT;
 
-    init_pre.enable = false;
+    /* leave the prescaler enabled and toggle only the primary timer */
+    init_pre.enable = true;
     init_pre.prescale = timerPrescale1;
-
     init_tim.enable = false;
     init_tim.clkSel = timerClkSelCascade;
 
@@ -101,68 +134,175 @@ int timer_init(tim_t dev, unsigned long freq, timer_cb_t callback, void *arg)
     /* enable interrupts for the channels */
     TIMER_IntClear(tim, TIMER_IFC_CC0 | TIMER_IFC_CC1 | TIMER_IFC_CC2);
     TIMER_IntEnable(tim, TIMER_IEN_CC0 | TIMER_IEN_CC1 | TIMER_IEN_CC2);
+}
+
+int timer_init(tim_t dev, unsigned long freq, timer_cb_t callback, void *arg)
+{
+    /* test if given timer device is valid */
+    if (dev >= TIMER_NUMOF) {
+        return -1;
+    }
+
+    /* save callback */
+    isr_ctx[dev].cb = callback;
+    isr_ctx[dev].arg = arg;
+
+    if (_is_letimer(dev)) {
+        _letimer_init(dev, freq);
+    } else {
+        _timer_init(dev, freq);
+    }
 
     NVIC_ClearPendingIRQ(timer_config[dev].irq);
     NVIC_EnableIRQ(timer_config[dev].irq);
 
-    /* start the timers */
-    TIMER_Enable(tim, true);
-    TIMER_Enable(pre, true);
+    timer_start(dev);
 
     return 0;
 }
 
 int timer_set_absolute(tim_t dev, int channel, unsigned int value)
 {
-    TIMER_TypeDef *tim;
+    if (!_is_letimer(dev)) {
+        TIMER_TypeDef *tim = timer_config[dev].timer.dev;
 
-    if (channel < 0 || channel >= (int) CC_CHANNELS) {
-        return -1;
+        if (channel < 0 || channel >= TIMER_CHANNEL_NUMOF) {
+            return -1;
+        }
+
+        /* this accounts for some timer being 16-bit and others 32-bit */
+        if (value > TIMER_TopGet(tim)) {
+            return -1;
+        }
+
+        tim->CC[channel].CCV = (uint32_t) value;
+        tim->CC[channel].CTRL = TIMER_CC_CTRL_MODE_OUTPUTCOMPARE;
     }
+    else {
+        LETIMER_TypeDef *tim = timer_config[dev].timer.dev;
 
-    /* this accounts for some timer being 16-bit and others 32-bit */
-    if (value > TIMER_TopGet(timer_config[dev].timer.dev)) {
-        return -1;
+        /* LETIMER is countdown only, so we invert the value */
+        value = 0xffff - value;
+        LETIMER_CompareSet(tim, channel, value);
+
+        switch (channel)
+        {
+            case 0:
+                LETIMER_IntClear(tim, LETIMER_IFC_COMP0);
+                LETIMER_IntEnable(tim, LETIMER_IEN_COMP0);
+                break;
+            case 1:
+                LETIMER_IntClear(tim, LETIMER_IFC_COMP1);
+                LETIMER_IntEnable(tim, LETIMER_IEN_COMP1);
+                break;
+            default:
+                return -2;
+                break;
+        }
     }
 
-    tim = timer_config[dev].timer.dev;
-    tim->CC[channel].CCV = (uint32_t) value;
-    tim->CC[channel].CTRL = TIMER_CC_CTRL_MODE_OUTPUTCOMPARE;
-
     return 0;
 }
 
 int timer_clear(tim_t dev, int channel)
 {
-    timer_config[dev].timer.dev->CC[channel].CTRL = _TIMER_CC_CTRL_MODE_OFF;
+    if (!_is_letimer(dev)) {
+        TIMER_TypeDef *tim = timer_config[dev].timer.dev;
+        tim->CC[channel].CTRL = _TIMER_CC_CTRL_MODE_OFF;
+    }
+    else {
+        LETIMER_TypeDef *tim = timer_config[dev].timer.dev;
+        switch (channel)
+        {
+            case 0:
+                LETIMER_IntDisable(tim, LETIMER_IEN_COMP0);
+                LETIMER_IntClear(tim, LETIMER_IFC_COMP0);
+                break;
+            case 1:
+                LETIMER_IntDisable(tim, LETIMER_IEN_COMP1);
+                LETIMER_IntClear(tim, LETIMER_IFC_COMP1);
+                break;
+            default:
+                return -1;
+        }
+    }
     return 0;
 }
 
 unsigned int timer_read(tim_t dev)
 {
-    return (unsigned int) TIMER_CounterGet(timer_config[dev].timer.dev);
+    if (_is_letimer(dev)) {
+        /* LETIMER is countdown only, so we invert the value */
+        return (unsigned int) 0xffff
+                    - LETIMER_CounterGet(timer_config[dev].timer.dev);
+    }
+    else {
+        return (unsigned int) TIMER_CounterGet(timer_config[dev].timer.dev);
+    }
 }
 
 void timer_stop(tim_t dev)
 {
-    TIMER_Enable(timer_config[dev].timer.dev, false);
+    if (_is_letimer(dev)) {
+        LETIMER_TypeDef *tim = timer_config[dev].timer.dev;
+        if (tim->STATUS & LETIMER_STATUS_RUNNING) {
+            pm_unblock(EFM32_LETIMER_PM_BLOCKER);
+        }
+        LETIMER_Enable(timer_config[dev].timer.dev, false);
+    }
+    else {
+        TIMER_TypeDef *tim = timer_config[dev].timer.dev;
+        if (tim->STATUS & TIMER_STATUS_RUNNING) {
+            pm_unblock(EFM32_TIMER_PM_BLOCKER);
+        }
+        TIMER_Enable(timer_config[dev].timer.dev, false);
+    }
 }
 
 void timer_start(tim_t dev)
 {
-    TIMER_Enable(timer_config[dev].timer.dev, true);
+    if (_is_letimer(dev)) {
+        LETIMER_TypeDef *tim = timer_config[dev].timer.dev;
+        if (!(tim->STATUS & LETIMER_STATUS_RUNNING)) {
+            pm_block(EFM32_LETIMER_PM_BLOCKER);
+        }
+        LETIMER_Enable(timer_config[dev].timer.dev, true);
+    }
+    else {
+        TIMER_TypeDef *tim = timer_config[dev].timer.dev;
+        if (!(tim->STATUS & TIMER_STATUS_RUNNING)) {
+            pm_block(EFM32_TIMER_PM_BLOCKER);
+        }
+        TIMER_Enable(timer_config[dev].timer.dev, true);
+    }
 }
 
 #ifdef TIMER_0_ISR
 void TIMER_0_ISR(void)
 {
-    TIMER_TypeDef *tim = timer_config[0].timer.dev;
+    tim_t dev = 0;
 
-    for (int i = 0; i < (int) CC_CHANNELS; i++) {
-        if (tim->IF & (TIMER_IF_CC0 << i)) {
-            tim->CC[i].CTRL = _TIMER_CC_CTRL_MODE_OFF;
-            tim->IFC = (TIMER_IFC_CC0 << i);
-            isr_ctx[0].cb(isr_ctx[0].arg, i);
+    if (_is_letimer(dev)) {
+        LETIMER_TypeDef *tim = timer_config[dev].timer.dev;
+
+        for (int i = 0; i < TIMER_CHANNEL_NUMOF; i++) {
+            if (tim->IF & (LETIMER_IF_COMP0 << i))
+            {
+                LETIMER_IntDisable(tim, LETIMER_IEN_COMP0 << i);
+                LETIMER_IntClear(tim, LETIMER_IFC_COMP0 << i);
+                isr_ctx[dev].cb(isr_ctx[dev].arg, i);
+            }
+        }
+    }
+    else {
+        TIMER_TypeDef *tim = timer_config[dev].timer.dev;
+
+        for (int i = 0; i < TIMER_CHANNEL_NUMOF; i++) {
+            if (tim->IF & (TIMER_IF_CC0 << i)) {
+                tim->CC[i].CTRL = _TIMER_CC_CTRL_MODE_OFF;
+                tim->IFC = (TIMER_IFC_CC0 << i);
+                isr_ctx[dev].cb(isr_ctx[dev].arg, i);
+            }
         }
     }
     cortexm_isr_end();