iC-MSBSAFETY, iC-MSB2
SIN/COS SIGNAL CONDITIONER WITH 1Vpp DRIVER
Rev D2, Page 15/29
BIAS SOURCE AND TEMPERATURE SENSOR CALIBRATION
Bias Source Calibration
The necessary activation threshold voltage VTth(T1) is
The calibration of the bias current source in operation then calculated. The required warning temperature T2,
mode Calibration 1 (Tab. 13) is prerequisite for adher- temperature coefficients TCs and TCth (see Electrical
ence to the given electrical characteristics and also in- Characteristics, Section E) and measurement value
strumental in the determination of the chip timing (e.g. VTs(T1) are entered into this calculation:
SCL clock frequency). For setup purposes the IBN
value is measured using a 10 kΩ resistor by pin VDDS
connected to pin NC. The setpoint is 200 µA which is
equivalent to a measurement voltage of 2 V.
VTs(T1) + TCs · (T2 − T1)
VTth(T1) =
1 + TCth · (T2 − T1)
CFGIBN
Code k
0x0
Adr 0x01, bit 7:4
Example: For T2 = T1 + 100 K, VTth(T1) must be pro-
grammed to 443 mV.
31
39−k
31
39−k
IBN ∼
Code k
0x8
IBN ∼
100 %
103 %
107 %
111 %
115 %
119 %
124 %
129 %
79 %
81 %
84 %
86 %
88 %
91 %
94 %
97 %
0x1
0x9
Activation threshold voltage VTth(T1) is provided for a
high impedance measurement (10 MΩ) at output pin
NS (measurement versus VDDS) and must be set by
programming CFGTA(3:0) to the calculated value.
0x2
0xA
0xB
0xC
0xD
0xE
0xF
0x3
0x4
0x5
0x6
Example: Altering VTth(T1) from 310 mV (measured
with CFGTA(3:0)= 0x0) to 443 mV is equivalent to
143 %, the closest value for CFGTA is 0x9;
0x7
Table 11: Bias Current Source Calibration
CFGTA
Code k
0x0
Adr 0x01, bit 3:0
65+3k
VTth ∼
65
65+3k
65
Code k
0x8
VTth ∼
140 %
145 %
150 %
155 %
160 %
165 %
170 %
175 %
Temperature Sensor
The temperature monitor is calibrated in operating
mode Calibration Mode 3.
100 %
105 %
110 %
115 %
120 %
125 %
130 %
135 %
0x1
0x9
0x2
0xA
0xB
0xC
0xD
0xE
0xF
0x3
To set the required warning temperature T2 the tem-
perature sensor voltage VTs at which the warning is
generated is first determined. To this end a volt-
age ramp from VDDS towards GNDS is applied to
pin PS until pin ERR triggers an error message (for
EMASKA = 0x20 and EMTD = 0x00).
0x4
0x5
0x6
0x7
Notes
With CFGTA = 0xF Toff is 80 °C typ.,
with CFGTA = 0x0 Toff is 155 °C typ.
Example: VTs(T1) is ca. 650 mV, measured from
VDDS versus PS, with T1 = 25 °C;
Table 12: Calibration of Temperature Monitoring
ICHAUS [ IC-HAUS GMBH ]
