diff --git a/lark1fq/src/ltc2640.c b/lark1fq/src/ltc2640.c
index 6141e77..1a9c629 100755
--- a/lark1fq/src/ltc2640.c
+++ b/lark1fq/src/ltc2640.c
@@ -66,19 +66,14 @@ void ltc2640_data_init(void)
 int32_t ltc2640_data_process(void)
 {
     uint8_t ch = 2;
-    uint32_t sig_ref;
     int32_t reading;
 
     if (flag.filter_climb > 0) {
         return VOLTAGE_400MV;
     }
 
-    sig_ref = device_data.gas_sig[ch];
-    if (sig_ref < data_ltc2640.sig_low || sig_ref > data_ltc2640.sig_high) {
-        return VOLTAGE_200MV;
-    }
-    sig_ref = device_data.gas_sig[data_gas_info.ref[ch]];
-    if (sig_ref < data_ltc2640.ref_low || sig_ref > data_ltc2640.ref_high) {
+    if ((device_data.detector_temperature < data_ltc2640.temperature_low) || \
+        (device_data.detector_temperature > data_ltc2640.temperature_high)) {
         return VOLTAGE_200MV;
     }