TLE7242-2G Datasheet, PDF (32/50 Pages) Infineon Technologies AG – 4 Channel Fixed Frequency Constant Current Control IC

TLE7242-2G
Functional Description and Electrical Characteristics
Response:
Current Set Point and Dither Amplitude Set
31 30 29 28 27 26 25 24 23 22 21
R/W
MSG_ID
CH1 CH0
EN
ON/
OFF
Reset Value: 00 00 00 00_H
20 19 18 17 16
Dither Step Size
15 14 13 12 11 10
9
8
7
6
5
4
3
2
1
0
Dither Step Size
Dither
ON/
OFF
Current Set Point
Field
MSG_ID
Channel
EN
Bits
30:26
25:24
23
ON/OFF
22
Step Size 21:12
Dither
11
ON/OFF
Current
10:0
Setpoint
Type
Description
Message Identifier
0 0011 = Current Set Point and Dither Amplitude Set
Channel Number
Sets behavior of channel when the pin ENABLE is low.
0 = channel turned off
1 = channel remains at last current set point.
Used when the channel is configured for on/off operation
0 = off
1 = on
Dither Step Size
(LSB value is 2^-4 of the Current Set point LSB)
Dither Enable
0=Disabled 1=Enabled
Average Current Set Point
Resolution = 0.78125 mA / bit when 0.2 ohm external resistor is used.
Dither_amplitude
[mApp]
=
2*
DitherStepSize *
2¹⁵
DitherSteps
∗
320
R_SENSE
Dither amplitude is the peak to peak amplitude of the dither waveform. Note: the actual dither waveform is
attenuated and phase shifted according to the frequency response of the control loop.
Dither Steps is the number of PWM periods in ¼ of the dither waveform, set in SPI message #4.
RSENSE is the value of the external sense resistor
Current _setpoint
[mA]
=
Setpoint
2¹¹
∗
320
R_SENSE
Data Sheet
32
Rev. 1.0, 2008-07-09