diff --git a/armsrc/mifarecmd.c b/armsrc/mifarecmd.c
index 0f101fed4..a8453868d 100644
--- a/armsrc/mifarecmd.c
+++ b/armsrc/mifarecmd.c
@@ -2702,17 +2702,17 @@ void MifareU_Otp_Tearoff(uint8_t arg0, uint32_t arg1, uint8_t *datain) {
     uint8_t data_testwrite[4] = {0x00};
     memcpy(data_fullwrite, datain, 4);
     memcpy(data_testwrite, datain + 4, 4);
-// optional authentication before?
 
     if (DBGLEVEL >= DBG_DEBUG) DbpString("Preparing OTP tear-off");
 
+    if (tearOffTime > 43000)
+        tearOffTime == 43000;
+
     LEDsoff();
     iso14443a_setup(FPGA_HF_ISO14443A_READER_LISTEN);
     clear_trace();
     set_tracing(true);
 
-    StartTicks();
-
     // write cmd to send, include CRC
     // 1b write, 1b block, 4b data, 2 crc
     uint8_t cmd[] = {MIFARE_ULC_WRITE, blockNo, data_testwrite[0], data_testwrite[1], data_testwrite[2], data_testwrite[3], 0, 0};
@@ -2732,10 +2732,10 @@ void MifareU_Otp_Tearoff(uint8_t arg0, uint32_t arg1, uint8_t *datain) {
 
     // Wait before cutting power.  aka tear-off
     LED_D_ON();
-    WaitUS(tearOffTime);
+
+    SpinDelayUsPrecision(tearOffTime);
     if (DBGLEVEL >= DBG_ERROR) Dbprintf(_YELLOW_("OTP tear-off triggered!"));
     switch_off();
 
     reply_ng(CMD_HF_MFU_OTP_TEAROFF, PM3_SUCCESS, NULL, 0);
-    StopTicks();
 }
diff --git a/client/src/cmdhfmfu.c b/client/src/cmdhfmfu.c
index ad3e0faa8..40923aa80 100644
--- a/client/src/cmdhfmfu.c
+++ b/client/src/cmdhfmfu.c
@@ -2850,6 +2850,10 @@ static int CmdHF14AMfuOtpTearoff(const char *Cmd) {
                     PrintAndLogEx(WARNING, "Wrong time limit number");
                     errors = true;
                 }
+                if (timeLimit > 43000) {
+                    PrintAndLogEx(WARNING, "You can't set delay out of 1..43000 range!");
+                    errors = true;
+                }
                 cmdp += 2;
                 break;
             case 's':
@@ -2941,14 +2945,12 @@ static int CmdHF14AMfuOtpTearoff(const char *Cmd) {
             else
                 snprintf(post_res, sizeof(post_res) - 1, _CYAN_("%s"), sprint_hex_inrow(post, sizeof(post)));
                 
-            
             PrintAndLogEx(INFO, "Result   %02d/0x%02X |  %s vs %s"
                     , blockNoUint
                     , blockNoUint
                     , sprint_hex_inrow(pre, sizeof(pre))
                     , post_res
                     );
-            
         } else {
             if (got_pre == false)
                 PrintAndLogEx(FAILED, "Failed to read block BEFORE");