SNL320
16-Bit LCD Controller
For 5V power system (3 batteries application), the power pin of core logic CVDD pin
should be connected to VOUR_REG in order to get an accurate 2.8V power.
Once chip entry power down mode, the regulator will also turn off automatically. And
this regulator also built-in a LVD circuit to detect the power dropping of VOUT_REG.
The regulator will auto turn on to re-charge the power of external CAP C1 when the
voltage of VOUT_REG is lower then 2.2V, it will make sure to provides enough
power for CVDD to keep the value of SRAM.
Note : If chip is halted , SNL320 internal Regulator will be disable
11. Low Voltage Detector
SNL320 built in a low voltage detector for power management. It provides four
different detect level, 2.3V, 2.5V, 2.8V and 3.1V. User can set an expect detect level
through the PCR control register and polling the acknowledge bit to get the current
power level is higher or lower then the detect level. Each detect level is designed by
schmitt trigger architecture, that’s means each detect level has a detect window.
For example, the detect window of detect level 2.3V is 2.24V ~ 2.36V. When the VDD
power down below 2.24V, the detect bit of PCR register will be set to 1. Once VDD
power is recovered and must be higher then 2.36V, then detect bit is clear by system.
Detect level Voltage window of schmitt trigger
2.3V
2.5V
2.8V
3.1V
2.24V ~ 2.36V
2.44V ~ 2.57V
2.72V ~ 2.88V
3.01V ~ 3.19V
12. EXTENSION BUS
SNL320 built-in a standard micro-controller interface extends the memory capability
through the extension bus. In additional, SNL320 both provides byte mode and word
mode access bus for external memory device in order to improve the efficiency.
This extension bus also allows users to connect different external devices for his own
application, such as ROM, RAM, NAND flash, 8-bit interface LCD controller etc.
There are 4 chip select pins for external devices, so totally SNL320 can connect 4
different devices. The maximum addressing capability of each external device is
64M-bit except CS0. Because the ROM bank of CS0 is shared with internal ROM of
SNL320, so the maximum addressing capability of CS0 is only 32M-bit. In additional,
user can put his program into each external memory device not only data.
Ver: 1.2
13
July 22, 2005
SONIX [ SONIX TECHNOLOGY COMPANY ]
