AS1112BQFT austriamicrosystems, AS1112BQFT Datasheet - Page 13

• Manufacturer Part Number: AS1112BQFT
• Description: IC, LED DRIVER, CONSTANT CURRENT, TQFN32
• Manufacturer: austriamicrosystems

Specifications of AS1112BQFT

• Led Driver Application: LED Displays, LED Signboards And Display Backlights
• No. Of Outputs: 16
• Output Current: 80mA
• Output Voltage: 15V
• Input Voltage: 3V To 5.5V
• Topology: Constant Current
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

AS1112
Data Sheet - D e t a i l e d D e s c r i p t i o n
Figure 12. Greyscale Data Input Timing Diagram
MODE
Status Information Data (SID)
The AS1112 contains an integrated status information register, which can be accessed in greyscale mode (MODE =
GND). Once the LD signal latches the data into the greyscale register, the input shift register data is replaced with sta-
tus information data
Open, shorted LED, temperature warning and overtemperature flags as well as the dot-correction registers can be
read out at pin SDO. The status information data packet is 192 bits wide. Bits 191:176 and 31:16 contain the open LED
detection status of each channel (either 191:176 or 31:16 can be used for readout). Bit 175 contains the thermal error
flag status. Bit 174 contains the temperature warning flag. Bits 167:72 contain the data of the dot-correction register. Bit
15:0 contains the LED shorted flags. The remaining bits are reserved. The complete status information data packet is
shown in
Figure 13. Status Information Data Packet Format
Greyscale PWM Operation
The falling edge of the OEN signal initiates a greyscale PWM cycle. The first GSCLK pulse after the falling edge of
OEN increments the greyscale counter by one and switches on any OUTn whose greyscale value does not equal zero.
Each subsequent rising edge of GSCLK increments the greyscale counter by one.
The AS1112 compares the greyscale value of each OUTn channel with the greyscale counter value. All OUTn whose
greyscale values equal the counter values are switched off. A OEN = 1 signal after 4096 GSCLK pulses resets the
greyscale counter to zero and completes a greyscale PWM cycle
www.austriamicrosystems.com
SDO
CLK
SDI
72:167
16:31
32:71
LD
Bit #
0:15
LOD15
MSB
Dot Correction Mode
191
Data Input Cycle
MSB-1
DCn-1
Figure
LED Open Detection (Optional, same as bits 176:191), LOD
Open LED
Detect
...
96
DCn-1
13.
LSB
t
H2
DCn-1
MSB
t
H3
(see Figure
LOD0
Dot Correction Readback (16 x 6 Bit)
176
t
SU2
LED Short Detection, LSD
x
TEF
Overtempera-
MSB
175
GSn
Data Input Cycle After Dot Correction Input
t
1
H0
Description
13).
ture
Undefined
x
TWF
t
174
SU3
1st Greyscale Mode
x
t
SU1
...
192
t
H3
Revision 1.04
168
X
GSn
LSB
DC15.
167
SIDn
MSB
(see Figure
DC Values
168:173
176:191
Bit #
174
175
...
GSn+1
MSB
Temperature Warning Flag (TWF, 125ºC, typ)
DC0.
1
72
Following Greyscale Mode
Temperature Error Flag (TEF, 150ºC, typ)
14).
MSB-1
SIDn
Data Input Cycle
LED Open Detection, LOD
71
X
MSB-2
SIDn
GSn+1
Description
Undefined
LSB
192
...
SIDn
LSB
16:31
LOD
LSB
0:15
LSD
SIDn
MSB
13 - 18