LP3944 Datasheet, PDF (5/12 Pages) National Semiconductor (TI) – RGB/White/Blue 8-LED Fun Light Driver

Electrical Characteristics (Continued)
Unless otherwise noted, V_DD = 5.5V. Typical values and limits appearing in normal type apply for T_J = 25˚C. Limits appearing
in boldface type apply over the entire junction temperature range for operation, T_J = −40˚C to +125˚C. (Note 5)
Symbol
Parameter
Conditions
Typical
Limit
Min
Max
Units
I²C INTERFACE (SCL AND SDA PINS)
t_CLK-LP
t_CLK-HP
t_SU
CLK Low Period
CLK High Period
Set-Up Time Repeated
START Condition
(Note 7)
(Note 7)
(Note 7)
1.3
µs
0.6
µs
0.6
µs
t_DATA-HOLD
t_DATA-SU
t_SU
Data Hold Time
Data Set-Up Time
Set-Up Time for STOP
Condition
(Note 7)
(Note 7)
(Note 7)
300
ns
100
ns
0.6
µs
t_TRANS
Maximum Pulse Width of
Spikes that Must Be
(Note 7)
Suppressed by the Input
50
ns
Filter of Both DATA & CLK
Signals
Note 1: Absolute Maximum Ratings are limits beyond which damage to the device may occur. Operating Ratings are conditions under which operation of the device
is guaranteed. Operating Ratings do not imply guaranteed performance limits. For guaranteed performance limits and associated test conditions, see the Electrical
Characteristics tables.
Note 2: All voltages are with respect to the potential at the GND pin.
Note 3: The Absolute Maximum power dissipation depends on the ambient temperature and can be calculated using the formula
P = (T_J — T_A)/θ_JA, (1)
where T_J is the junction temperature, T_A is the ambient temperature, and θ_JA is the junction-to-ambient thermal resistance. The 1.76W rating appearing under
Absolute Maximum Ratings results from substituting the Absolute Maximum junction temperature, 150˚C, for T_J, 85˚C for T_A, and 37˚C/W for θ_JA. More power can
be dissipated safely at ambient temperature below 85˚C. Less power can be dissipated safely at ambient temperatures above 85˚C. The Absolute Maximum power
dissipation can be increased by 27 mW for each degree below 85˚C, and it must be de-rated by 27 mW for each degree above 85˚C. For Operating Ratings
maximum power dissipation, T_J = 125˚C and T_A = 85˚C
Note 4: The human-body model is 100 pF discharged through 1.5 kΩ. The machine model is 0Ω in series with 220 pF.
Note 5: Limits are guaranteed. All electrical characteristics having room-temperature limits are tested during production with T_J = 25˚C. All hot and cold limits are
guaranteed by correlating the electrical characteristics to process and temperature variations and applying statistical process control.
Note 6: Each LED pin should not exceed 25 mA and the package should not exceed a total of 200 mA.
Note 7: Guaranteed by design.
Typical Performance Characteristics
Frequency vs. Temp
(T_A = −40˚C to +85˚C),
V_DD = 2.3V to 3.0V
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