Datasheet

DocID17659 Rev 9 105/131
STM32L151x6/8/B, STM32L152x6/8/B Electrical characteristics
105
6.3.21 LCD controller (STM32L152xx only)
The STM32L152xx embeds a built-in step-up converter to provide a constant LCD reference
voltage independently from the V
DD
voltage. An external capacitor C
ext
must be connected
to the V
LCD
pin to decouple this converter.
Table 62. LCD controller characteristics
Symbol Parameter Min Typ Max Unit
V
LCD
LCD external voltage - - 3.6
V
V
LCD0
LCD internal reference voltage 0 - 2.6 -
V
LCD1
LCD internal reference voltage 1 - 2.73 -
V
LCD2
LCD internal reference voltage 2 - 2.86 -
V
LCD3
LCD internal reference voltage 3 - 2.98 -
V
LCD4
LCD internal reference voltage 4 - 3.12 -
V
LCD5
LCD internal reference voltage 5 - 3.26 -
V
LCD6
LCD internal reference voltage 6 - 3.4 -
V
LCD7
LCD internal reference voltage 7 - 3.55 -
C
ext
V
LCD
external capacitance 0.1 - 2 µF
I
LCD
(1)
1. LCD enabled with 3 V internal step-up active, 1/8 duty, 1/4 bias, division ratio= 64, all pixels active, no LCD
connected
Supply current at V
DD
= 2.2 V - 3.3 -
µA
Supply current at V
DD
= 3.0 V - 3.1 -
R
Htot
(2)
2. Guaranteed by design, not tested in production.
Low drive resistive network overall value 5.28 6.6 7.92 MΩ
R
L
(2)
High drive resistive network total value 192 240 288 kΩ
V
44
Segment/Common highest level voltage - - V
LCD
V
V
34
Segment/Common 3/4 level voltage - 3/4 V
LCD
-
V
V
23
Segment/Common 2/3 level voltage - 2/3 V
LCD
-
V
12
Segment/Common 1/2 level voltage - 1/2 V
LCD
-
V
13
Segment/Common 1/3 level voltage - 1/3 V
LCD
-
V
14
Segment/Common 1/4 level voltage - 1/4 V
LCD
-
V
0
Segment/Common lowest level voltage 0 - -
ΔVxx
(3)
3. Based on characterization, not tested in production.
Segment/Common level voltage error
T
A
= -40 to 85 °C
--± 50 mV