FAQ
14
2012.11 Ver.00
effect might not be played back successfully. Instead of using the default
750koHm charging resistor to ramp up, user can choose a 5k resistor for faster
ramping up. This can be done by setting register 0x36 bit[0-2] as 001, or simply
writing 0x01 into register 0x36.
6.3 Unlock an ISD3800 device
In many cases, the device might be locked due to the bad memory content.
For example, if a device’s PU VM accidently ends with a PD command, then
the device will never be able to power up. In this case, users can utilize the
following sequence to unlock the device
o
Without powering the board, pull down the ISD3800 pin28 FDO ( or
SOP-8 flash pin5) to ground.
o
Power the board
o
Send power-up command and wait till power-up finishes.
o
Leave the pin28 FDO floating.
o
Chip-erase the ISD3800.
6.4 Solve the programming failure issue
ISD3800 can be configured as trigger play device. In some cases, the
triggering setting may conflict with MCU SPI lines during programming. The
symptom is that VPE shows verification failure after “burn device”.
A simple yet effective way to avoid this error is that before device programming,
erase and reset the device first. Thus the trigger condition is removed and no
longer in effect
– reset an empty device initialize all the register settings to their
default values, so the device becomes easy to operation with again.
