7
Rev. 0
OPERATING THE BOARD IN STAND-ALONE MODE (WITHOUT SDP-K1)
Figure 9. OUT and OUTBAR Typical Waveforms
1. Power:
a. Stand-alone Operation: Move switch S1 slider to the
left (towards VIN test point), connect a low-noise
5V power supply between VIN and GND test points
to power the board.
2. Apply the external -120V DC power supply to P7 (pin
2) with pin 1 tied to power supply ground. This is
the appropriate bias volage for the APDs installed on
the board. The connector and passives are rated up
to 300V. See Figure 4 for the proper P7 high voltage
polarity connection.
3. Connect OUT and OUTBAR SMAs to an oscilloscope
with at least two channels that is 50Ω terminated on
each input. The output(s) are DC coupled. With the
device internal 50Ω terminations (TERM and TERMBAR
pins tied to OUT and OUTBAR respectively), each output
will then see a net 25Ω load or 50Ω diff load.
4. Move the board jumpers to the positions stated in
Table 1 for stand-alone operation.
5. Analog Controls: The following are analog controls
which can be varied by applying the voltage desired
to the turrets (test points) on the board (see Table 1):
CM, Tilt, Offset, HI.
The allowable voltage range on these four turrets are
0V – 2.5V. Alternatively, SDP-K1 (if present) controller
board can vary these via a DAC (U2) on-board.
Move the miniature 3-pin shorting jumpers next to
each of these four turrets to the bottom (away from
P8) for external voltage control, or alternatively to the
top (towards P8) for SDP-K1 (if present) control.
6. Digital Controls: The following device pins can take on
either 0 or 1 state (3.3V):
CHSEL0, CHSEL1, MUX, SHDN (or PWRMD), ADJ1,
ADJ0.
Move the miniature 3-pin shorting jumpers next to
each turret to the bottom (away from P8, silkscreen
A) for state 1, or to the top (towards P8, silkscreen B)
for state 0.
Alternatively, remove the shorting jumpers from these
6 jumpers and move to the top 2 pin headers next to
each control, in order to enable SDP-K1 (if present)
control instead.
7. Apply a 400nm to 1100nm wavelength pulsed laser,
similar to the one identified in the Equipment List as
the ST micro light source, to the APDs, which are
identified in Figure 1. With a 5ns duration laser pulse
width from this light source, the Figure 9 typical scope
waveforms can be expected at OUT and OUTBAR SMAs
(Ch1: OUT, Ch2: OUTBAR):
The LTC6563 EVAL board is now setup in stand-alone mode.
