diff --git a/UNITTESTS/drivers/PwmOut/test_pwmout.cpp b/UNITTESTS/drivers/PwmOut/test_pwmout.cpp
new file mode 100644
index 0000000000..4ea807cc70
--- /dev/null
+++ b/UNITTESTS/drivers/PwmOut/test_pwmout.cpp
@@ -0,0 +1,258 @@
+/*
+ * Copyright (c) 2019 Arm Limited and affiliates.
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "gtest/gtest.h"
+#include "gmock/gmock.h"
+#include "drivers/PwmOut.h"
+
+using namespace mbed;
+
+class MbedPowerMgmtInterface {
+public:
+    virtual ~MbedPowerMgmtInterface() {}
+    virtual void sleep_manager_unlock_deep_sleep_internal() = 0;
+    virtual void sleep_manager_lock_deep_sleep_internal() = 0;
+};
+
+
+class MockMbedPowerMgmt : public MbedPowerMgmtInterface {
+public:
+    virtual ~MockMbedPowerMgmt() {}
+
+    MOCK_METHOD0(sleep_manager_unlock_deep_sleep_internal, void());
+    MOCK_METHOD0(sleep_manager_lock_deep_sleep_internal, void());
+
+    static MockMbedPowerMgmt *get_instance()
+    {
+        if (_instance == nullptr) {
+            _instance = new MockMbedPowerMgmt();
+        }
+
+        ++_ref_counter;
+
+        return _instance;
+    }
+
+    static void release_instance()
+    {
+        --_ref_counter;
+
+        if ((_instance != nullptr) && (_ref_counter == 0)) {
+            delete _instance;
+            _instance = nullptr;
+        }
+    }
+
+    static void sleep_manager_unlock_deep_sleep()
+    {
+        // Do not increment the call count unless it's done by a test
+        // case.
+        if (_instance) {
+            _instance->sleep_manager_unlock_deep_sleep_internal();
+        }
+    }
+
+    static void sleep_manager_lock_deep_sleep()
+    {
+        // Do not increment the call count unless it's done by a test
+        // case.
+        if (_instance) {
+            _instance->sleep_manager_lock_deep_sleep_internal();
+        }
+    }
+
+    MockMbedPowerMgmt(MockMbedPowerMgmt const &) = delete;
+    void operator=(MockMbedPowerMgmt const &) = delete;
+private:
+    MockMbedPowerMgmt() {}
+    static MockMbedPowerMgmt *_instance;
+    static int _ref_counter;
+};
+MockMbedPowerMgmt *MockMbedPowerMgmt::_instance = nullptr;
+int MockMbedPowerMgmt::_ref_counter = 0;
+
+
+void sleep_manager_unlock_deep_sleep(void)
+{
+    MockMbedPowerMgmt::sleep_manager_unlock_deep_sleep();
+}
+
+
+void sleep_manager_lock_deep_sleep(void)
+{
+    MockMbedPowerMgmt::sleep_manager_lock_deep_sleep();
+}
+
+
+class TestPwmOut : public testing::Test {
+protected:
+    PwmOut *pwm_obj;
+    MockMbedPowerMgmt *mbed_mgmt_mock;
+
+    void SetUp()
+    {
+        pwm_obj = new PwmOut(PTC1);
+        // Create a mock object singleton after the PwmOut object
+        // instantiation so the sleep_manager_lock_deep_sleep call by the
+        // constructor does not increment the call count.
+        // Now it is ok because a test case is about to start.
+        mbed_mgmt_mock = MockMbedPowerMgmt::get_instance();
+    }
+
+    void TearDown()
+    {
+        // Destroy the mock object singleton before the PwmOut destruction
+        // because it will increment the sleep_manager_unlock_deep_sleep call
+        // count.
+        MockMbedPowerMgmt::release_instance();
+        delete pwm_obj;
+    }
+};
+// *INDENT-ON*
+
+
+/** Test if the constructor locks deepsleep
+    Given an instantiated Pmw
+    When the constructor is called
+    Then the deep sleep lock is acquired
+ */
+TEST_F(TestPwmOut, test_constructor)
+{
+    using ::testing::Mock;
+
+    EXPECT_CALL(
+        *mbed_mgmt_mock, sleep_manager_lock_deep_sleep_internal()
+    ).Times(1);
+
+    PwmOut pmw(PTC1);
+
+    // Force gMock to verify a mock object singleton before it is destructed
+    // by the teardown
+    Mock::VerifyAndClearExpectations(mbed_mgmt_mock);
+    // Suppress the memory leak error. The mock singleton will be released and
+    // deleted in the TearDown call.
+    Mock::AllowLeak(mbed_mgmt_mock);
+}
+
+
+/** Test if the destructor unlocks deepsleep
+    Given an instantiated Pmw
+    When the destructor is called
+    Then the deep sleep lock is released
+ */
+TEST_F(TestPwmOut, test_destructor)
+{
+    using ::testing::Mock;
+
+    EXPECT_CALL(
+        *mbed_mgmt_mock, sleep_manager_unlock_deep_sleep_internal()
+    ).Times(1);
+
+    PwmOut *pmw = new PwmOut(PTC1);
+    delete pmw;
+
+    // Force gMock to verify a mock object singleton before it is destructed
+    // by the teardown
+    Mock::VerifyAndClearExpectations(mbed_mgmt_mock);
+    // Suppress the memory leak error. The mock singleton will be released and
+    // deleted in the TearDown call.
+    Mock::AllowLeak(mbed_mgmt_mock);
+}
+
+
+/** Test if `suspend` unlocks deepsleep
+
+    Given an initialised Pmw with a deep sleep lock
+    When the instance is suspended
+    Then the deep sleep lock is released once
+ */
+TEST_F(TestPwmOut, test_suspend)
+{
+    using ::testing::Mock;
+
+    EXPECT_CALL(
+        *mbed_mgmt_mock, sleep_manager_unlock_deep_sleep_internal()
+    ).Times(1);
+    pwm_obj->suspend();
+    pwm_obj->suspend();
+
+    // Force gMock to verify a mock object singleton before it is destructed
+    // by the teardown
+    Mock::VerifyAndClearExpectations(mbed_mgmt_mock);
+    // Suppress the memory leak error. The mock singleton will be released and
+    // deleted in the TearDown call.
+    Mock::AllowLeak(mbed_mgmt_mock);
+}
+
+
+/** Test if `resume` lock deepsleep
+
+    Given an initialised Pmw in a suspended state
+    When the instance is resumed
+    Then the deep sleep lock is re-acquired once
+ */
+TEST_F(TestPwmOut, test_resume)
+{
+    using ::testing::Mock;
+
+    EXPECT_CALL(
+        *mbed_mgmt_mock, sleep_manager_lock_deep_sleep_internal()
+    ).Times(1);
+
+    pwm_obj->suspend();
+    pwm_obj->resume();
+    pwm_obj->resume();
+
+    // Force gMock to verify a mock object singleton before it is destructed
+    // by the teardown
+    Mock::VerifyAndClearExpectations(mbed_mgmt_mock);
+    // Suppress the memory leak error. The mock singleton will be released and
+    // deleted in the TearDown call.
+    Mock::AllowLeak(mbed_mgmt_mock);
+}
+
+/** Test if `suspend`/`resume` unlock/lock deepsleep multiple times
+
+    Given an initialised Pmw
+    When the instance is suspended and then resumed
+    Then the deep sleep lock can be unlocked and then locked again and again
+ */
+TEST_F(TestPwmOut, test_multiple_suspend_resume)
+{
+    using ::testing::Mock;
+
+    const int suspend_resume_max_cycle = 3;
+
+    EXPECT_CALL(
+        *mbed_mgmt_mock, sleep_manager_unlock_deep_sleep_internal()
+    ).Times(suspend_resume_max_cycle);
+    EXPECT_CALL(
+        *mbed_mgmt_mock, sleep_manager_lock_deep_sleep_internal()
+    ).Times(suspend_resume_max_cycle);
+
+    for (int i = 0; i < suspend_resume_max_cycle; i++) {
+        pwm_obj->suspend();
+        pwm_obj->resume();
+    }
+
+    // Force gMock to verify a mock object singleton before it is destructed
+    // by the teardown
+    Mock::VerifyAndClearExpectations(mbed_mgmt_mock);
+    // Suppress the memory leak error. The mock singleton will be released and
+    // deleted in the TearDown call.
+    Mock::AllowLeak(mbed_mgmt_mock);
+}
diff --git a/UNITTESTS/drivers/PwmOut/unittest.cmake b/UNITTESTS/drivers/PwmOut/unittest.cmake
new file mode 100644
index 0000000000..475cf0ae94
--- /dev/null
+++ b/UNITTESTS/drivers/PwmOut/unittest.cmake
@@ -0,0 +1,28 @@
+
+####################
+# UNIT TESTS
+####################
+set(TEST_SUITE_NAME "PwmOut")
+
+# Add test specific include paths
+set(unittest-includes ${unittest-includes}
+  .
+  ../hal
+)
+
+# Source files
+set(unittest-sources
+  ../drivers/source/PwmOut.cpp
+)
+
+# Test files
+set(unittest-test-sources
+  drivers/PwmOut/test_pwmout.cpp
+  stubs/mbed_critical_stub.c
+  stubs/mbed_assert_stub.c
+  stubs/pwmout_api_stub.c
+)
+
+# defines
+set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -DDEVICE_PWMOUT")
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -DDEVICE_PWMOUT")
diff --git a/UNITTESTS/stubs/pwmout_api_stub.c b/UNITTESTS/stubs/pwmout_api_stub.c
new file mode 100644
index 0000000000..1eae62b0ca
--- /dev/null
+++ b/UNITTESTS/stubs/pwmout_api_stub.c
@@ -0,0 +1,61 @@
+/*
+ * Copyright (c) 2019 Arm Limited and affiliates.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#include "hal/pwmout_api.h"
+
+#if DEVICE_PWMOUT
+
+void pwmout_init(pwmout_t *obj, PinName pin)
+{
+}
+
+void pwmout_free(pwmout_t *obj)
+{
+}
+
+void pwmout_write(pwmout_t *obj, float percent)
+{
+}
+
+float pwmout_read(pwmout_t *obj)
+{
+    return 0;
+}
+
+void pwmout_period(pwmout_t *obj, float seconds)
+{
+}
+
+void pwmout_period_ms(pwmout_t *obj, int ms)
+{
+}
+
+void pwmout_period_us(pwmout_t *obj, int us)
+{
+}
+
+void pwmout_pulsewidth(pwmout_t *obj, float seconds)
+{
+}
+
+void pwmout_pulsewidth_ms(pwmout_t *obj, int ms)
+{
+}
+
+void pwmout_pulsewidth_us(pwmout_t *obj, int us)
+{
+}
+
+#endif // DEVICE_PWMOUT
diff --git a/UNITTESTS/target_h/PinNames.h b/UNITTESTS/target_h/PinNames.h
index 243c64fd14..f580d15ae6 100644
--- a/UNITTESTS/target_h/PinNames.h
+++ b/UNITTESTS/target_h/PinNames.h
@@ -34,6 +34,10 @@ typedef enum {
 } PinName;
 
 typedef enum {
+    PullNone = 0,
+    PullDown = 1,
+    PullUp   = 2,
+    PullDefault = PullUp
 } PinMode;
 
 #ifdef __cplusplus
diff --git a/UNITTESTS/target_h/objects.h b/UNITTESTS/target_h/objects.h
index 5753bbdcd4..13f95e1992 100644
--- a/UNITTESTS/target_h/objects.h
+++ b/UNITTESTS/target_h/objects.h
@@ -18,6 +18,7 @@
 #ifndef MBED_OBJECTS_H
 #define MBED_OBJECTS_H
 
+#include <stdint.h>
 #include "PeripheralNames.h"
 #include "PinNames.h"
 
@@ -33,6 +34,12 @@ struct serial_s {
     int x;
 };
 
+struct pwmout_s {
+    int pwm_name;
+};
+
+
+
 #include "gpio_object.h"
 
 #ifdef __cplusplus
diff --git a/UNITTESTS/target_h/platform/mbed_power_mgmt.h b/UNITTESTS/target_h/platform/mbed_power_mgmt.h
index d0475a10d7..5ebb18c095 100644
--- a/UNITTESTS/target_h/platform/mbed_power_mgmt.h
+++ b/UNITTESTS/target_h/platform/mbed_power_mgmt.h
@@ -21,6 +21,7 @@
  */
 #ifndef MBED_POWER_MGMT_H
 #define MBED_POWER_MGMT_H
+
 extern void mock_system_reset();
 
 MBED_NORETURN static inline void system_reset(void)
@@ -28,5 +29,9 @@ MBED_NORETURN static inline void system_reset(void)
     mock_system_reset();
 }
 
+void sleep_manager_unlock_deep_sleep(void);
+
+void sleep_manager_lock_deep_sleep(void);
+
 #endif
 
diff --git a/drivers/source/PwmOut.cpp b/drivers/source/PwmOut.cpp
index 2951bbe414..ef0c8821a8 100644
--- a/drivers/source/PwmOut.cpp
+++ b/drivers/source/PwmOut.cpp
@@ -37,7 +37,6 @@ PwmOut::PwmOut(PinName pin) :
 
 PwmOut::~PwmOut()
 {
-    MBED_ASSERT(!_initialized);
     PwmOut::deinit();
 }