LTC3208EUH#PBF Linear Technology, LTC3208EUH#PBF Datasheet - Page 13

• Manufacturer Part Number: LTC3208EUH#PBF
• Description: IC LED DRIVR QVGA DISPLAY 32-QFN
• Manufacturer: Linear Technology
• Type: QVGA Display (I²C Interface)r

Specifications of LTC3208EUH#PBF

• Topology: Step-Up (Boost), Switched Capacitor (Charge Pump)
• Number Of Outputs: 17
• Internal Driver: Yes
• Type - Primary: Backlight
• Type - Secondary: RGB, White LED
• Frequency: 600kHz ~ 1.2MHz
• Voltage - Supply: 2.9 V ~ 4.5 V
• Mounting Type: Surface Mount
• Package / Case: 32-QFN
• Operating Temperature: -40°C ~ 85°C
• Internal Switch(s): Yes
• Efficiency: 95%
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Voltage - Output: -
• Current - Output / Channel: -

OPERATIO
R
The current set resistor is connected between RREF and
ground. The value of this resistor should typically be near
24k since all of the DAC reference currents and support
circuit currents are related to this set current.
This input is protected against shorts to ground or low
value resistors <10k. When a fault is detected the reference
current amplifi er is current limited. In addition, the current
source outputs and charge pump are disabled.
Fullscale LED Current Equations
SUB MAIN fullscale LED current Amps
CAM fullscale LED current Amps
RGB fullscale LED current Amps
AUX fullscale LED current Amps
REF
/
Current Set Resistor
SDA
SCL
START
0
0
1
U
0
0
2
SDA
SCL
t
HD, STA
1
1
3
CONDITION
ADDRESS
START
1
1
4
(
(
(
0
0
5
t
LOW
1
1
6
(
)
)
)
t
1
r
=
=
1
7
=
t
HIGH
1 215
1 215
t
1 215
SU, DAT
WR
0
.
R
.
R
0
8
.
R
REF
REF
REF
)
t
f
ACK
=
9
V
V
1 215
V
R
.
S7
S7
•
•
1
•
RE
Figure 5. Timing Parameters
518
533
t
202
HD, DAT
Figure 4. Bit Assignments
F F
S6
S6
2
V
5 5
• 543
S5
S5
3
SUB-ADDRESS
S4
S4
4
REPEATED START
CONDITION
S3
S3
5
Mode Switching
The LTC3208 will automatically switch from 1x mode
to 1.5x mode and subsequently to 2x mode whenever
a dropout condition is detected at an LED pin. Dropout
occurs when a current source voltage becomes too low
for the programmed current to be supplied. The dropout
delay is typically 400µs.
The mode will automatically switch back to 1x whenever
a data bit is updated via the I
pin switches from high to low.
I
The LTC3208 communicates with a host (master) using
the standard I
(Figure 5) shows the timing relationship of the signals on
the bus. The two bus lines, SDA and SCL, must be high
when the bus is not in use. External pull-up resistors or
current sources, such as the LTC1694 SMBus accelerator,
are required on these lines.
The LTC3208 is a receive-only (slave) device.
2
S2
S2
6
C Interface
t
SU, STA
S1
S1
7
t
HD, STA
S0
S0
t
8
SP
ACK
9
2
7
1
7
C 2-wire interface. The Timing Diagram
2
6
6
5
3
5
CONDITION
STOP
DATA BYTE
4
4
4
t
SU, STO
t
2
5
BUF
3
3
C port or when the CAMHL
CONDITION
2
6
START
2
3208 F05
1
7
1
0
8
0
LTC3208
ACK
9
STOP
3208 FO4
13
3208fa