Add MCP47A1 DAC output (#3014)

esphome/components/mcp47a1/mcp47a1.cpp

@@ -0,0 +1,21 @@
+#include "mcp47a1.h"
+#include "esphome/core/helpers.h"
+#include "esphome/core/log.h"
+
+namespace esphome {
+namespace mcp47a1 {
+
+static const char *const TAG = "mcp47a1";
+
+void MCP47A1::dump_config() {
+  ESP_LOGCONFIG(TAG, "MCP47A1 Output:");
+  LOG_I2C_DEVICE(this);
+}
+
+void MCP47A1::write_state(float state) {
+  const uint8_t value = remap(state, 0.0f, 1.0f, 63, 0);
+  this->write_byte(0, value);
+}
+
+}  // namespace mcp47a1
+}  // namespace esphome