AK8999A Datasheet, PDF (31/68 Pages) Asahi Kasei Microsystems – Pressure Sensor Control IC

CONFIDENTIAL
[AK8999A/AW/AD]
Address : 10 hex D[3:0] = EFR[3:0]
EFR[3:0]
Ratio Frequency Δf
Dec Hex
Bin
(%)
(kHz)
-5 B
1011
-34
-251
-4 C
1100
-25
-197
-3 D
1101
-17
-146
-2 E
1110
-11
-99
-1 F
1111
-5
-52
0
0
0000
0
0
1
1
0001
5
49
2
2
0010
10
106
3
3
0011
14
162
4
4
0100
18
224
5
5
0101
22
274
6
6
0110
25
329
7
7
0111
28
384
Note1) Hex 8 to A are prohibited for setup.
Description
Default
When High level period is not 2msec, the ideal value of CT [7:0] can be calculated as follows.
Considering the calculated ideal value as 100%, and a ratio should be redefined. Please set the
adjustment data of oscillation frequency as the sum of the ratio of CT [7:0] data and the ratio of
EFR [3:0] data is close to 0%.
Count value[time] = High time[msec] / 2 * 100
ex.) In the case of 3 msec, 100time → 150time.
1.4) VTMP Adjustment (completed when shipped in package form)
Temperature sensor output (VTMP) voltage is adjusted to match the VREF voltage.
When the external temperature sensor is used, connect the external temperature sensor to the EXTMP
pin, and set up a measurement mode 1 EEPROM (address: 0Dh, data: ETMP[1:0] = 0 or 1h).
VTMP voltage is observed at VOUT pin while the CSCLK pin High (CSCLK High Time) after the
writing of an adjustment mode register (C address: 00h, data: AM[3:0] = 4h).
*At the VTMP adjustment using the external temperature sensor, the External Temperature Sensor
Drive circuit is normal ON in the sampling frequency 8.33kHz mode (ESF[0] = 0h).
If the actual operationg condition is the sampling frequency 0.83kHz mode (ESF[0] = 1h), AK8999A
operates intermittent. The external temoperature sensor output voltage may be different from the voltage
after the VTMP adjustment.
Twr_REG CSCLK High Time
1
4
9
16
1
CSCLK
VOUT
Analog
Output
Hi-z
VTMP monitor
I2
MS1600-E-00
- 31 -
2014/05