ltc3220 Linear Technology Corporation, ltc3220 Datasheet - Page 6

• Manufacturer Part Number: ltc3220
• Description: 360ma Universal 18-channel Led Driver
• Manufacturer: Linear Technology Corporation

LTC3220/LTC3220-1
TYPICAL PERFORMANCE CHARACTERISTICS
PIN FUNCTIONS
ULED1-ULED18 (Pins 1-9,13-21): Current Source Outputs
for Driving LEDs. The LED current can be set from 0mA
to 20mA in 64 steps via software control and internal
6-bit linear DAC. Each output can be disabled by setting
the associated data register REG1 to REG18 low. ULED1
to ULED18 can also be used as I
general purpose outputs. Connect unused outputs to
ground.
6
16
14
12
10
8
6
4
0
2
0
1.5x Mode V
(I
VIN
– 1.5I
60
120
CPO
15
25
20
10
5
0
IN
ULED Current vs Input Code
0
I
)
CPO
Current vs I
180
(mA)
09
240
12
INPUT CODE (HEX)
CPO
300
1B
2
3220 G13
C controlled open-drain
24
360
2D
36
14
12
10
3220 G16
8
6
4
2
0
0
2x Mode V
(I
3F
VIN
60
– 2I
CPO
120
IN
)
Current vs I
I
CPO
180
DV
pin sets the logic reference level of the LTC3220/LTC3220-1.
DV
undervoltage lockout threshold. A 0.1μF X5R or X7R
ceramic capacitor should be connected to ground.
SCL (Pin 11): I
referenced to DV
(mA)
CC
CC
240
(Pin 10): Supply Voltage for All digital I/O lines. This
will reset the data registers when set below the
CPO
100
90
80
70
60
50
40
30
20
10
0
300
2.9
18-LED ULED Display Effi ciency
vs V
T
3220 G14
3.225
A
IN
= 25°C unless otherwise noted.
360
Voltage
2
3.55
C Clock Input. The logic level for SCL is
CC
.
3.875
V
IN
VOLTAGE (V)
25
20
15
10
5
0
4.2
0
ULED Pin Current
vs ULED Pin Voltage
4.525
4.85
0.05
ULED PIN VOLTAGE (V)
5.175
3220 G17
5.5
0.1
0.15
3220 G15
32201fb
0.2