W83627DHG Datasheet, PDF (43/268 Pages) Winbond – WINBOND LPC I/O

W83627DHG
7.3 Analog Inputs
The maximum input voltage on analog pins is 2.048 V because the 8-bit ADC has an 8-mV LSB.
Usually, the voltage ports of CPU Vcore (pin 100), battery (pin 74), 3VSB (pin 61), 3VCC (pin 12), and
AVCC (pin 95) can be directly connected to their respective analog pins, as illustrated in the figure
below.
Power Inputs
CPUVCORE
R1
V0
R2
Positive Voltage Input
VIN2
VIN3
AVCC
VBAT
3VSB
3VCC
VIN0
Pin 95
Pin 74
Pin 61
Pin 12
Pin 100
Pin 99
Pin 97
Pin 96
8-bit ADC
with
8mV LSB
V1
Negative Voltage Input
R3
VIN1
Pin 98
RTHM
10K@25 C, beta=3435K
R
10K, 1%
R
15K, 1%
CPUD+
CPUD-
(AGND)
CAP,2200p
VREF
AUXTIN
CPUTIN
SYSTIN
R4
Pin 102
Pin 103
Pin 104
Pin 101
CPUD-(AGND) ^{Pin 105}
As illustrated in the figure above, other connections may require some external circuits. The rest of this
section provides more information about voltages outside the range of the 8-bit ADC, CPU Vcore
voltage detection, and temperature sensing
7.3.1 Voltages Over 2.048 V or Less Than 0 V
Input voltages greater than 2.048 V should be reduced by external resistors to keep the input voltages
in the proper range. For example, input voltage V₀ (+12 V) should be reduced before it is connected to
VIN0 according to the following equation:
VIN 0 = V 0 × ^R2
R₁ + R₂
Publication Release Date: Aug, 22, 2007
-31-
Version 1.4