DocID022881 Rev 10
97/123
STM32L162VC, STM32L162RC
104
Figure 27. Maximum dynamic current consumption on V
REF+
supply pin during ADC
conversion
General PCB design guidelines
Power supply decoupling should be performed as shown in
. The applicable
procedure depends on whether V
REF+
is connected to V
DDA
or not. The 100 nF capacitors
should be ceramic (good quality). They should be placed as close as possible to the chip.
ADC clock
Sampling (n cycles)
Conversion (12 cycles
)
I
ref+
300µA
700µA
MS36686V1
Table 58. Maximum source impedance R
AIN
max
(1)
Ts
(µs)
R
AIN
max (k
Ω
)
Ts (cycles)
f
ADC
=16 MHz
(2)
Multiplexed channels
Direct channels
2.4 V < V
DDA
< 3.6 V 1.8 V < V
DDA
< 2.4 V 2.4 V < V
DDA
< 3.6 V 1.8 V < V
DDA
< 2.4 V
0.25
Not allowed
Not allowed
0.7
Not allowed
4
0.5625
0.8
Not allowed
2.0
1.0
9
1
2.0
0.8
4.0
3.0
16
1.5
3.0
1.8
6.0
4.5
24
3
6.8
4.0
15.0
10.0
48
6
15.0
10.0
30.0
20.0
96
12
32.0
25.0
50.0
40.0
192
24
50.0
50.0
50.0
50.0
384
1. Guaranteed by design.
2. Number of samples calculated for f
ADC
= 16 MHz. For f
ADC
= 8 and 4 MHz the number of sampling cycles can be reduced
with respect to the minimum sampling time Ts (µs),