IC-MSA Datasheet, PDF (17/29 Pages) IC-Haus GmbH – SIN/COS SIGNAL CONDITIONER with AGC and 1Vpp DRIVER

iC-MSA SIN/COS SIGNAL
preliminary
CONDITIONER with AGC and 1Vpp DRIVER
TEST MODE
Rev A1, Page 17/29
iC-MSA switches to test mode if a voltage larger
than VTMon is applied to pin ERR (precondition:
TMODE(0) = 1). In response iC-MSA transmits its con-
figuration settings as current-modulated data using I/O
pin ERR after re-reading the EEPROM. If the voltage
at pin ERR falls below VTMoff test mode is terminated
and data transmission aborted.
The clock rate for the data output is determined by EN-
FAST. Two clock rates can be selected: 780 ns for EN-
FAST = 1 or 3.125 µs for ENFAST = 0 (see Elec. Char.
D08 for clock frequency and tolerances).
Data is output in Manchester code via two clock pulses
per bit. To this end the lowside current source switches
between a Z state (OFF = 0 mA) and an L state (ON =
2 mA).
The bit information lies in the direction of the current
source switch:
Zero bit: change of state Z → L (OFF to ON)
One bit: Change of state L → Z (ON to OFF)
Transmission consists of a start bit (a one bit), 8 data
bits and a pause interval in Z state (the timing is iden-
tical with an EEPROM access via the I²C interface).
Example: byte value = 1000 1010
Transmission including the start bit: 1 1000 1010
In Manchester code: LZ LZZL ZLZL LZZL LZZL
Decoding of the data stream:
ZZZZZZ LZ LZ ZL ZL ZL LZ ZL LZ ZL ZZZZZZ
Pause 1 1 0 0 0 1 0 1 0 Pause
If test mode is quit with TMODE = 0x00, iC-MSA con-
tinues operation without any interruption.
If test mode is quit with TMODE > 0x00, then iC-MSA
again reads out its configuration from the EEPROM ac-
cessible at the device ID filed to DEVID(6:0) of address
0x40.
In TMODE = 0x03 the EEPROM is read completely; in
all other cases only the address range 0x40 to 0x61 is
read to keep the configuration time for device testing
short.
TMODE
Code
00
01
10
11
Addr 0x55, bit 7:6
Function during test
mode
Normal operation
Transmission of
EEPROM data, address
range 0x5B-0x7F and
0x00-0x3F
Normal operation
Transmission of
EEPROM data, address
range 0x40-0x7F and
0x00-0x3F
Function following test
mode
Normal operation
Repeated read out of
EEPROM
Repeated read out of
EEPROM
Repeated read out of
EEPROM
Table 15: Test Mode Functions
VP
VP
C21
100nF
7
VP
U22-S
AD8029
VN
4
C22
100nF
8
VP
U23-S
LM393
GND
4
U23-B
VP LM393
6_-
7
5₊
JP4
ERR
DATA_ON
M22
IRLML6401
R26
100k
R28
51k
M21
2N7002
VP
R23
2K
D21
LL4148
R27
100k
R21
475k
R22
365k
8
U21
5
LM285
4
VDD
C23
100nF
R24
470
C24
100pF
U22-A
2-
AD8029
+ 3 NDIS
8
VP
U23-A
LM393
6
2_-
3₊
C25
100nF
max. 5V
VDD
C26
100nF
R25
2k
1
DATA_OUT
dra_mq1d_error_s c hem
Figure 1: Example circuit for the decoding and con-
version of the current-modulated signals
to logic levels.