ICS854S14I Datasheet, PDF (9/14 Pages) Integrated Device Technology – LOW SKEW, 1-TO-4 DIFFERENTIAL-TOLVDS FANOUT BUFFER

ICS854S14I
LOW SKEW, 1-TO-4 DIFFERENTIAL-TO-LVDS FANOUT BUFFER
PRELIMINARY
RECOMMENDATIONS FOR UNUSED INPUT AND OUTPUT PINS
INPUTS:
LVCMOS CONTROL PINS:
All control pins have internal pull-ups; additional resistance is
not required but can be added for additional protection. A 1kΩ
resistor can be used.
OUTPUTS:
LVDS Output
All unused LVDS outputs can be left floating. We recommend
that there is no trace attached. Both sides of the differential output
pair should either be left floating or terminated.
2.5V LVDS DRIVER TERMINATION
Figure 3 shows a typical ter mination for LVDS driver in
characteristic impedance of 100Ω differential (50Ω single)
2.5V
LVDS_Driv er
transmission line environment. For buffer with multiple LVDS
driver, it is recommended to terminate the unused outputs.
2.5V
+
R1
100
-
100 Oh₁m_00ΩD_Diff_ie_ffr_ee_ren_nti_ta_ial_lTT_rr_aa_nn_ss_mm_isi_ss_is_oi_no_Ln_inL_eine
FIGURE 3. TYPICAL LVDS DRIVER TERMINATION
THERMAL RELEASE PATH
The expose metal pad provides heat transfer from the device to
the P.C. board. The expose metal pad is ground pad connected
to ground plane through thermal via. The exposed pad on the
device to the exposed metal pad on the PCB is contacted through
solder as shown in Figure 4. For further information, please refer
to the Application Note on Surface Mount Assembly of Amkor’s
Thermally /Electrically Enhance Leadframe Base Package, Amkor
Technology.
SOLDER M ASK
SIGNAL
TRACE
EXPOSED PAD
SOLDER
SIGNAL
TRACE
GROUND PLANE
THERMAL VIA
Expose Metal Pad
(GROUND PAD)
FIGURE 4. P.C. BOARD FOR EXPOSED PAD THERMAL RELEASE PATH EXAMPLE
IDT^™ / ICS^™ LVDS FANOUT BUFFER
9
ICS854S14AKI REV. A FEBRUARY 23, 2007