diff --git a/tests/test_plugins/test_microwave.py b/tests/test_plugins/test_microwave.py
new file mode 100644
index 0000000000..1193f6926c
--- /dev/null
+++ b/tests/test_plugins/test_microwave.py
@@ -0,0 +1,138 @@
+import pytest
+
+
+import tidy3d as td
+from tidy3d.plugins.microwave import VoltageIntegralAA, CurrentIntegralAA
+
+from tidy3d.exceptions import DataError
+from ..utils import run_emulated
+
+
+def makesim():
+    sim = td.Simulation(
+        size=(1, 1, 1),
+        grid_spec=td.GridSpec.auto(wavelength=1.0),
+        monitors=[
+            td.FieldMonitor(center=(0, 0, 0), size=(1, 1, 1), freqs=[2e14], name="field"),
+            td.FieldMonitor(
+                center=(0, 0, 0), size=(1, 1, 1), freqs=[2e14], fields=["Ex", "Hx"], name="ExHx"
+            ),
+            td.ModeMonitor(
+                center=(0, 0, 0), size=(1, 1, 0), freqs=[2e14], mode_spec=td.ModeSpec(), name="mode"
+            ),
+        ],
+        sources=[
+            td.PointDipole(
+                center=(0, 0, 0),
+                polarization="Ex",
+                source_time=td.GaussianPulse(freq0=2e14, fwidth=1e13),
+            )
+        ],
+        run_time=2e-12,
+    )
+    return sim
+
+
+@pytest.mark.parametrize("axis", [0, 1, 2])
+def test_voltage_integral_axes(axis):
+    length = 0.5
+    size = [0, 0, 0]
+    size[axis] = length
+    center = [0, 0, 0]
+    voltage_integral = VoltageIntegralAA(
+        center=center,
+        size=size,
+    )
+    sim = makesim()
+    sim_data = run_emulated(sim)
+    _ = voltage_integral.compute_voltage(sim_data["field"].field_components)
+
+
+@pytest.mark.parametrize("axis", [0, 1, 2])
+def test_current_integral_axes(axis):
+    length = 0.5
+    size = [length, length, length]
+    size[axis] = 0.0
+    center = [0, 0, 0]
+    current_integral = CurrentIntegralAA(
+        center=center,
+        size=size,
+    )
+    sim = makesim()
+    sim_data = run_emulated(sim)
+    _ = current_integral.compute_current(sim_data["field"].field_components)
+
+
+def test_voltage_integral_toggles():
+    length = 0.5
+    size = [0, 0, 0]
+    size[0] = length
+    center = [0, 0, 0]
+    voltage_integral = VoltageIntegralAA(
+        center=center,
+        size=size,
+        extrapolate_to_endpoints=True,
+        snap_path_to_grid=True,
+        sign="-",
+    )
+    sim = makesim()
+    sim_data = run_emulated(sim)
+    _ = voltage_integral.compute_voltage(sim_data["field"].field_components)
+
+
+def test_current_integral_toggles():
+    length = 0.5
+    size = [length, length, length]
+    size[0] = 0.0
+    center = [0, 0, 0]
+    current_integral = CurrentIntegralAA(
+        center=center,
+        size=size,
+        extrapolate_to_endpoints=True,
+        snap_contour_to_grid=True,
+        sign="-",
+    )
+    sim = makesim()
+    sim_data = run_emulated(sim)
+    _ = current_integral.compute_current(sim_data["field"].field_components)
+
+
+def test_voltage_missing_fields():
+    length = 0.5
+    size = [0, 0, 0]
+    size[1] = length
+    center = [0, 0, 0]
+    voltage_integral = VoltageIntegralAA(
+        center=center,
+        size=size,
+    )
+    sim = makesim()
+    sim_data = run_emulated(sim)
+    with pytest.raises(DataError):
+        _ = voltage_integral.compute_voltage(sim_data["ExHx"].field_components)
+
+
+def test_current_missing_fields():
+    length = 0.5
+    size = [length, length, length]
+    size[0] = 0.0
+    center = [0, 0, 0]
+    current_integral = CurrentIntegralAA(
+        center=center,
+        size=size,
+    )
+    sim = makesim()
+    sim_data = run_emulated(sim)
+    with pytest.raises(DataError):
+        _ = current_integral.compute_current(sim_data["ExHx"].field_components)
+
+
+def test_tiny_voltage_path():
+    length = 0.05
+    size = [0, 0, 0]
+    size[1] = length
+    center = [0, -0.05, 0]
+    voltage_integral = VoltageIntegralAA(center=center, size=size, extrapolate_to_endpoints=True)
+    sim = makesim()
+    sim_data = run_emulated(sim)
+    _ = voltage_integral.compute_voltage(sim_data["field"].field_components)