diff --git a/docs/library/pyb.ADC.rst b/docs/library/pyb.ADC.rst
index 1256c6a3c1..679ba2f5ac 100644
--- a/docs/library/pyb.ADC.rst
+++ b/docs/library/pyb.ADC.rst
@@ -170,44 +170,7 @@ The ADCAll Object
     The default value is 0xffffffff which means all analog inputs are active. If just the internal
     channels (16..18) are required, the mask value should be 0x70000.
  
-    It is possible to access channle 16..18 values without incurring the side effects of ``ADCAll``::
-    
-        def adcread(chan):                              # 16 temp 17 vbat 18 vref
-            assert chan >= 16 and chan <= 18, 'Invalid ADC channel'
-            start = pyb.millis()
-            timeout = 100
-            stm.mem32[stm.RCC + stm.RCC_APB2ENR] |= 0x100 # enable ADC1 clock.0x4100
-            stm.mem32[stm.ADC1 + stm.ADC_CR2] = 1       # Turn on ADC
-            stm.mem32[stm.ADC1 + stm.ADC_CR1] = 0       # 12 bit
-            if chan == 17:
-                stm.mem32[stm.ADC1 + stm.ADC_SMPR1] = 0x200000 # 15 cycles
-                stm.mem32[stm.ADC + 4] = 1 << 23
-            elif chan == 18:
-                stm.mem32[stm.ADC1 + stm.ADC_SMPR1] = 0x1000000
-                stm.mem32[stm.ADC + 4] = 0xc00000
-            else:
-                stm.mem32[stm.ADC1 + stm.ADC_SMPR1] = 0x40000
-                stm.mem32[stm.ADC + 4] = 1 << 23
-            stm.mem32[stm.ADC1 + stm.ADC_SQR3] = chan
-            stm.mem32[stm.ADC1 + stm.ADC_CR2] = 1 | (1 << 30) | (1 << 10) # start conversion
-            while not stm.mem32[stm.ADC1 + stm.ADC_SR] & 2: # wait for EOC
-                if pyb.elapsed_millis(start) > timeout:
-                    raise OSError('ADC timout')
-            data = stm.mem32[stm.ADC1 + stm.ADC_DR]     # clear down EOC
-            stm.mem32[stm.ADC1 + stm.ADC_CR2] = 0       # Turn off ADC
-            return data
-
-        def v33():
-            return 4096 * 1.21 / adcread(17)
-
-        def vbat():
-            return  1.21 * 2 * adcread(18) / adcread(17)  # 2:1 divider on Vbat channel
-
-        def vref():
-            return 3.3 * adcread(17) / 4096
-
-        def temperature():
-            return 25 + 400 * (3.3 * adcread(16) / 4096 - 0.76)
-
-    Note that this example is only valid for the F405 MCU and all values are not corrected by Vref and
-    factory calibration data.
+    Example::
+
+        adcall = pyb.ADCAll(12, 0x70000) # 12 bit resolution, internal channels
+        temp = adcall.read_core_temp()