STLED325QTR STMicroelectronics, STLED325QTR Datasheet - Page 21

• Manufacturer Part Number: STLED325QTR
• Description: LED Lighting Drivers I2C interfaced LED controller/driver
• Manufacturer: STMicroelectronics

Specifications of STLED325QTR

• Product Category: LED Lighting Drivers
• Rohs: yes
• Input Voltage: 5 V
• Maximum Supply Current: 2 mA
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Package / Case: QFN-32
• Minimum Operating Temperature: - 40 C
• Power Dissipation: 1200 mW

STLED325
3.11.4
WDFEn = watchdog flag enable
12/24 = 12 hour or 24 hour format (‘0’ for 24-hour format and ‘1’ for 12-hour format). For 12
hour PM display, the 8th segment of last digit (digit 4) is driven to indicate PM mode through
a dot on the last digit.
It is recommended to fill the unused bits in the register map to 0 upon a cold boot up. The
timekeepers and alarm store data in BCD format, while the calibration, watchdog bits are in
binary format.
The structure of the frame is shown below. For RTC, all the Dig1 to Dig4 must be configured
to show the proper time.
Figure 8.
If the date programmed in the RTC exceeds a valid date value, then the RTC does not
function as desired. So the invalid dates should never be programmed into the RTC.
Setting alarm clock registers
Address locations 0Ah-0Eh contain the alarm settings. The alarm can be configured to go
off at a prescribed time on a specific month, date, hour, minute, or second or repeat every
year, month, day, hour, minute, or second. It can also be programmed to go off while the
STLED325 is in the standby mode to serve as a system wake-up call.
Bits RPT6-RPT1 put the alarm in the repeat mode of operation. Codes not listed in the table
default to the once per second mode to quickly alert the user of an incorrect alarm setting.
Note that by default, the alarm repeat mode is enabled and by default the repeat frequency
is set to “once per year”.
Address locations 0Ah to 0Eh contain the alarm settings. The alarm can be configured to go
off at a prescribed time. The default repeat alarm mode is once per year. Programming the
RPT[6:1] bits changes the repeat alarm mode.
Keyscan and digit mapping
Keyscan
discrete LED)
(used for
Doc ID 17576 Rev 1
Digit 5
Dig 1
Dig 2
Dig 3
Dig 4
Functional description
AM08722V1
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