ZMID520x User Guide for Getting Started
© 2018 Integrated Device Technology, Inc.
17
April 6, 2018
4.
Internal Memory
Figure 17 shows the internal memory structure of the ZMID520x products, which is divided into a nonvolatile EEPROM and a volatile shadow
RAM (SWR) section. After the ZMID520x start up, the EEPROM content is copied into the SWR. During ZMID520x operation in OWI mode,
changes in the SWR will take immediate effect; whereas changes in the EEPROM require a memory WRITE command or a ZMID520x power
cycle (power off / power on).
Figure 17. ZMID520x Internal Memory
Memory
EEPROM
Shadow Register
(SWR)
Communication IF
One Wire Interface (OWI)
1F
HEX
00
HEX
1F
HEX
00
HEX
PPU
Output
Traceability
Others
Table 1.
EEPROM and Shadow RAM Contents
Address
Type
Location
Function
00
HEX
R/W
EEPROM/SWR
This register value is the 14-bit zero-angle offset of output signal, which is used for device
calibration and sets the offset value of the output transfer function.
01
HEX
R/W
EEPROM/SWR
This register value is the 13-bit slope value of output signal, which is used for device
calibration and sets the slope value of the output transfer function.
02
HEX
R/W
EEPROM/SWR
This register value is used with the analog and PWM output protocols in order to clamp the
upper and lower output levels of the transfer function respectively below 95% and above 5%.
03
HEX
R/W
EEPROM/SWR
This register value is used in linearization. The position transfer function can be modified by a
correction curve over the whole position range. The correction curve is defined by 9
linearization points. This register contains the correction factor for points n°2 and n°1. Bits
[15:8] are the correction factor for the position at 12.5% (45°), and bits [7:0] are the correction
factor for the position at 0% (0°).
04
HEX
R/W
EEPROM/SWR
This register value is used in linearization (see register 03
HEX
for description). This register
contains the correction factor for points n°4 and n°3.
Bits [15:8] are the correction factor for the position at 37.5% (135°), and bits [7:0] are the
correction factor for the position at 25% (90°).