c644ultrt Semtech Corporation, c644ultrt Datasheet - Page 5
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c644ultrt
Manufacturer Part Number
c644ultrt
Description
Light Management Unit With 4 Ldos And Sempulse Interface
Manufacturer
Semtech Corporation
Datasheet
1.C644ULTRT.pdf
(26 pages)
Electrical Characteristics (continued)
Notes:
() Capacitors are MLCC of X5R type. Production tested with higher value capacitors than the application requires.
(2) SPIF is high for more than 0ms
(3) Subscript for all backlights (BLn), n = , 2, 3, 4, 5, and 6. Subscripting for all LDOs (LDOn), n = , 2, 3, 4.
(4) Current matching is defined as ± [I
(5) Test voltage is V
(6) Subscript m = , 3, and 4 and applies only to LDO, LDO3, and LDO4.
(7) Dropout is defined as (V
(8) X5R or better “temperature stable” MLCC capacitor.
(9) The source driver used to provide the SemPulse output must meet these limits.
(0) The SemPulse start-up time is the minimum time that the SPIF pin must be held high to enable the part before commencing
() The SemPulse shutdown time is the minimum time that the SPIF pin must be pulled low to shut the part down.
Parameter
Digital I/O Electrical Specifications (SPIF)
Input High Threshold
Input Low Threshold
Input High Current
Input Low Current
SemPulse Electrical Specifications (SPIF)
SemPulse Start-up Time
Bit Pulse Duration
Duration Between Bits
Hold Time - Address
Hold Time - Data
Bus Reset Time
Shutdown Time
Fault Protection
Output Short Circuit Current Limit
Over-Temperature
Charge Pump
Over-Voltage Protection
Under Voltage Lockout
of .8V.
communication.
(9)
()
(9)
(9)
OUT
(9)
(9)
(9)
= 4.2V — a relatively extreme LED voltage — to force a transition during test. Typically V
(9)
(0)
IN
- V
LDOm
) when V
BL(MAX)
Symbol
V
V
LDOm
t
I
t
UVLO-OFF
UVLO-HYS
OUT(SC)
- I
HOLDD
V
HOLDA
T
T
V
V
t
t
t
t
t
I
I
OTP
HYS
OVP
IH
SU
LO
BR
SD
IL
HI
BL(MIN)
IH
IL
drops 00mV from nominal. Dropout does not apply to LDO2 since it has a maximum output voltage
] / [I
BL(MAX)
+ I
BL(MIN)
OUT pin open circuit, V
].
OUT pin shorted to GND
SPIF is pulled low
SPIF is held high
SPIF is held high
SPIF is held high
Rising threshold
Increasing V
Conditions
Hysteresis
Hysteresis
V
V
V
V
IN
IN
IN
IN
= 5.5V
= 2.9V
= 5.5V
= 5.5V
IN
OUT
= V
OVP
Min
0.75
0.75
500
500
.6
0
0
OUT
-
-
= 3.2V for white LEDs.
Typ
300
65
800
5.7
2.7
30
Max
5000
250
250
0.4
6.0
+
+
SC644
Units
mA
mV
µA
µA
ms
ms
ms
µs
µs
µs
µs
°C
°C
V
V
V
V
5
5