IC-MQ_15 Datasheet, PDF (33/43 Pages) IC-Haus GmbH – Sin/Cos INTERPOLATION IC WITH RS422 DRIVER

iC-MQ PROGRAMMABLE 9-BIT
Sin/Cos INTERPOLATION IC WITH RS422 DRIVER
TEST MODE
Rev F3, Page 33/43
iC-MQ switches to test mode if a voltage larger
than VTMon is applied to pin ERR (precondition:
EMODE(0) = 1). In response iC-MQ transmits its con-
figuration settings as current-modulated data using I/O
pin ERR either directly from the RAM (for EMODE2 = 1)
or after re-reading the EEPROM (for EMODE2 = 0). 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
ENFAST. Two clock rates can be selected: 780 ns for
ENFAST = 1 or 3.125 µs for ENFAST = 0 (see Electri-
cal Characteristics, B12, for clock frequency and toler-
ances).
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 identi-
cal 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 EMODE = 0x00, iC-MQ contin-
ues operation without any interruption.
If test mode is quit with EMODE > 0x00, then iC-MQ
again reads out its configuration from the EEPROM ac-
cessible at the device ID filed to DEVID(6:0) of address
0x00.
In EMODE = 0x03 the EEPROM is read completely; in
all other cases only the address range 0x00 to 0x31 is
read to keep the configuration time for device testing
short.
EMODE
Code
00
01
10
11
Addr 0x15, bit 7:6
Function during test
mode
Normal operation
EMODE2 = 0:
Transmission of
EEPROM data
0x24-0x7F:
OEM data and
registered errors
EMODE2 = 1:
Transmission of
RAM data 0x3B-0x43:
OEM data (4 bytes) and
current errors
Normal operation
Transmission of
EEPROM data
(0x00-0x7F)
Function terminating test
mode
Normal operation
Repeated read out of
EEPROM
(MODE = 0: 0x00-0x7F)
(MODE > 0: 0x00-0x31)
Repeated read out of
EEPROM
(MODE = 0: 0x00-0x7F)
(MODE > 0: 0x00-0x31)
Repeated read out of
EEPROM
(0x00-0x7F)
Table 61: Test Mode Functions
EMODE2
Code
0
1
Addr 0x18, bit 7
Memory selection
EEPROM
iC-MQ RAM (ENSL = 1)
Table 62: Test Mode Memory Selection
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_-
+ ³
AD8029
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 14: Example circuit for the decoding and con-
version of the current-modulated signals
to logic levels.