AKM AK2571, Руководство пользователя

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AKM Confidential AK2571
Figure 4-7 PWM division
Operation cycle (8ms typ)
TS#1
TS#2 TS#3 TS#4
Minimum pulse width = 8ms/8192
≅
1us
Resolution=8192
Case-1
PID control value(R_PID_VALABS) = 2020
PWM division = 32
8192/32=256
64
TS#5 TS#6 TS#32
64 64 64 63 63 63
63
64
1us
256
Operation cycle (8ms typ)
TS#1 TS#2 TS#3
8192/16=128
32
32*36 + 31*28 = 2020
Case-2
PID control value(R_PID_VALABS) = 2020
PWM division = 64
64*4 + 63*28 = 2020
32 32
TS#4
32
TS#5
32
TS#6
32
TS#7
32
TS#8
32
TS#9
32 31 31 31
TS#64
31
TS#63 TS#62 TS#61
4.4 Gain & Offset
The AK2571 amplifies (typically x13) the input signal from the thermister to provide higher resolution for the 8-bit ADC. It
also adds an offset voltage to meet the middle of full scale at target temperature. Table 4-6 indicates temperature levels
that correspond to ADC values when using a thermister
R0=10kohm@25degree , B=3900 and Table 4-7 indicates a
thermister R0=10kohm@25degree , B=3450. Both load resistances RL) are 6.8kohm, REFOUT is 2.3V. When adjusting
Offset voltage (R_ATC_OFFSET), target temperature must be a value between 96 (60h) and 160 (A0h).
<Rev. 0.6E Preliminary> -18- 2001/11