LTC3220-1_15 Datasheet, PDF (7/20 Pages) Linear Technology – 360mA Universal 18-Channel LED Driver

LTC3220/LTC3220-1
PIN FUNCTIONS
SDA (Pin 12): Input Data for the Serial Port. Serial data is
shifted in one bit per clock cycle to control the LTC3220/
LTC3220-1. The logic level is referenced to DV_CC.
C1P, C2P, C1M, C2M (Pins 27, 26, 23, 22): Charge Pump
Flying Capacitor Pins. A 2.2μF X7R or X5R ceramic ca-
pacitor should be connected from C1P to C1M and C2P
to C2M.
V_IN (Pin 24): Supply Voltage for the Entire Device. This pin
must be bypassed with a single 2.2μF low ESR ceramic
capacitor.
RST (Pin 25): Active Low Reset Input. RST Resets all
internal registers and forces LTC3220/LTC3220-1 into
shutdown mode.
CPO (Pin 28): Output of the Charge Pump. Used to power
all LEDs. A 4.7μF X5R or X7R ceramic capacitor should
be connected to ground.
Exposed Pad (Pin 29): Ground. The Exposed Pad must
be soldered to PCB ground.
BLOCK DIAGRAM
V_IN
24
DV_CC
10
RST
25
SDA
12
SCL
11
850kHz
OSCILLATOR
27
23
26
22
C1P C1M C2P C2M
CHARGE PUMP
EXPOSED
PAD
29
CPO
28
1.22V
CONTROL
LOGIC
MASTER/SLAVE
REG
18
18 UNIVERSAL
CURRENT SOURCES
AND DACS
ULED1
1
ULED2
2
ULED3
3
ULED4
4
ULED5
5
ULED6
6
ULED7
7
ULED8
8
SHIFT REGISTER
ULED18 ULED17 ULED16 ULED15 ULED14 ULED13 ULED12 ULED11 ULED10 ULED9
21
20
19
18
17
16
15
14
13
9
3220 BD
32201fc
7