MIC2860-2DYC6 TR Micrel Inc, MIC2860-2DYC6 TR Datasheet - Page 8

• Manufacturer Part Number: MIC2860-2DYC6 TR
• Description: IC WHITE LED DVR 2CH SC-70-6
• Manufacturer: Micrel Inc
• Series: -r

Specifications of MIC2860-2DYC6 TR

• Constant Current: -
• Constant Voltage: -
• Topology: Linear (LDO)
• Number Of Outputs: 2
• Internal Driver: Yes
• Type - Primary: Backlight
• Type - Secondary: White LED
• Frequency: -
• Voltage - Supply: 3 V ~ 5.5 V
• Voltage - Output: 0 V ~ 5.5 V
• Mounting Type: Surface Mount
• Package / Case: 6-TSSOP, SC-88, SOT-363
• Operating Temperature: -40°C ~ 85°C
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 576-3896-2

Application Information
Digital Dimming Interface
The MIC2860-2D incorporates an easy to use single
wire, serial programming interface that allows users to
set WLED brightness up to 32 different levels as shown
in Table 2. To calculate the brightness level for other
R
values by the maximum LED current set by the R
resistor value from table 1.
For example with R
(brightness level = 31) is 15.1mA and brightness level 20
would equate to 15.1mA x 0.646 = 9.7mA.
Level (0 - 31)
Micrel Inc.
Brightness
July 2010
SET
Table 2. Digital Interface Brightness Level Table
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
15
14
13
12
11
10
values, multiply the percentage of max current
9
8
7
6
5
4
3
2
1
0
R
SET
I
LED
20.1
19.4
18.8
18.2
17.5
16.8
16.2
15.6
14.9
14.2
13.6
13.0
12.3
11.6
11.0
10.4
=14.3kΩ
9.7
9.1
8.5
7.8
7.1
6.5
5.9
5.2
4.5
3.9
3.3
2.6
1.9
1.3
0.7
0.3
(mA)
SET
= 19.1kΩ, the max current
R
SET
I
LED
=19.1kΩ
15.1
14.6
14.1
13.6
13.1
12.6
12.2
11.7
11.2
10.7
10.2
9.7
9.2
8.7
8.3
7.8
7.3
6.8
6.4
5.8
5.3
4.8
4.4
3.9
3.4
2.9
2.4
1.9
1.4
0.9
0.5
0.2
(mA)
% of Max.
Current
96.7
93.7
90.4
87.1
83.8
80.8
77.5
74.2
70.9
67.9
64.6
61.3
57.9
55.0
51.7
48.3
45.0
42.1
38.7
35.4
32.1
29.1
25.8
22.5
19.2
16.2
12.9
100
9.6
6.3
3.3
1.7
SET
8
Brightness levels are linearly spaced with a maximum
current equal to 100% of the current set by R
MIC2860-2D is designed to receive programming pulses
to decrease brightness from the initial start up default
(level 1 maximum current). Once the brightness change
signal is received, the SC pin is simply pulled high to
maintain the brightness. This “set and forget” feature
relieves processor computing power by eliminating the
need to constantly send a PWM signal to the dimming
pin.
Start Up
Assuming the MIC2860-2D has been off for a long time,
the MIC2860-2D will start-up in its default mode
approximately 33µs (t
applied to the SC pin. In the default mode the WLEDs
are turned on at the maximum brightness (level 31).
Each falling edge will cause the default brightness level
to decrease by one.
Shutdown
When the SC input pin is pulled low for a period greater
than or equal to t
turn off the current sinks as shown in Figure 4.
Once the device is shutdown, the control circuit supply is
disabled and the WLEDs are turned off drawing only
0.01µA. Brightness level information stored in the
MIC2860-2D prior to shutdown will be erased and upon
a following startup signal the WLEDs will be turned on at
maximum brightness (level 31).
Programming the Brightness Level
MIC2860-2D is designed to start driving the WLEDs
Figure 3. Typical Start-Up Timing
Figure 4. Shutdown Timing
SHUTDOWN
START_UP
(500µs), the MIC2860-2D will
) after a logic level high is
M9999-072010-A
MIC2860-2D
SET
. The