W83627EHF Datasheet, PDF (32/141 Pages) Winbond – evolving product from Winbonds most popular I/O family

W83627EHF/EF, W83627EHG/EG
6.3 Analog Inputs
The maximum input voltage of the analog pin is 2.048V because the 8-bit ADC has a 8mV LSB. Really,
the application of the PC monitoring would most often be connected to power suppliers. The CPU
Vcore voltage , battery(pin 74), 3VSB(pin 61), 3VCC(pin 12) , AVCC(pin 114) voltage can directly
connected to these analog inputs. The +12V voltage inputs should be reduced a factor with external
resistors so as to obtain the input range. As Figure 6.2 shows.
Power Inputs
CPUVCORE
R1
V0
Positive Voltage Input
VIN2
VIN3
VIN4
V1
Negative Voltage Input
R2
R3
AVCC
VBAT
VSB
3VCC
VIN0
Pin 114
Pin 74
Pin 61
Pin 12
Pin 64
Pin 99
VIN1
Pin 97
Pin 96
Pin 95
8-bit ADC
with
8mV LSB
Pin 98
RTHM
10K@25 C, beta=3435K
R
10K, 1%
R
15K, 1%
CPUD+
CPUD-
CAP,2200p
VREF
AUXTIN
CPUTIN
SYSTIN
R4
Pin 102
Pin 103
Pin 104
Pin 101
AGND
Pin 117
Figure 6.2
6.3.1 Monitor over 2.048V voltage
The +12V input voltage can be expressed as following equation.
VIN 0 = V 0 × ^R2
R₁ + R₂
The value of R1 and R2 can be selected to 56K Ohms and 10K Ohms, respectively, when the input
voltage V₀ is 12V. The node voltage of VIN0 can be subject to less than 2.048V for the maximum input
range of the 8-bit ADC.
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