Datasheet

Maxim Integrated │ 2
www.maximintegrated.com
Evaluates: MAX14970
MAX14970 Evaluation Kit
Detailed Description of Hardware
The MAX14970 evaluation kit (EV kit) evaluates the
MAX14970 dual-channel buffer. The device is designed
to redrive SATA and eSATA signals. The EV kit is divided
into four sections: application circuit, characterization cir-
cuit, and two sets of calibration traces.
The application circuit utilizes 100Ω differential controlled-
impedance traces and provides two SATA connectors
(J1 and J2), allowing for evaluation of the device in a
SATA environment. The characterization circuit utilizes
50Ω controlled-impedance traces and SMA input/output
connectors, allowing for eye diagrams, and input/output
return-loss measurements.
The lower half of the EV kit provides two sets of calibra-
tion traces, all of which are matched to the trace lengths in
the characterization circuit. These traces provide a refer-
ence for determining the performance of only the device
when evaluated in the characterization circuit.
The device has a cable-detect feature (CAD).
Application Circuit (U1)
The application circuit provides the means for evaluating
the device in a SATA application. This section of the EV
kit provides two SATA connectors (J1 and J2), one for
connection to a SATA host (e.g., a PC), and the other for
connection to a SATA device (e.g., a hard drive).
Input Supply (VIN)
The application circuit must be powered by +3.3V. There
are two ways to get this voltage, either from the on-board
LDO linear regulator (U3), or directly connected to a
+3.3V power supply. When using the on-board voltage
regulator, the LDO can be powered by the 4-pin Molex
connector (H1), or by a +5V external supply connected to
the VIN and GND PCB pads. When using the on-board
LDO linear regulator to supply power, there is a power
LED (D1) to indicate the presence of +3.3V at VCC.
The user can also connect directly to a +3.3V supply,
which is available on a SATA power connector. The shunt
should be removed from jumper JU4 and a wire con-
nected from the SATA power pin to pin 2 (right-most pin)
of jumper JU4 (see Table 2).
Device Enable (JU1)
The application circuit is enabled/disabled by configur-
ing jumper JU1 (see Table 3). When disabled the device
buffers are powered down and the part is placed in a
low-power mode. When enabled and no SATA device is
plugged in (CAD is unconnected), the device enters a
low-power mode. Once a SATA device is plugged in (CAD
grounded) the device goes into active mode.
*Default configuration.
*Default configuration.
SHUNT
POSITION
VCC PIN (U1) DESCRIPTION
Installed*
Connected to the
on-board LDO
linear regulator
output
U1 powered by the LDO
linear regulator output
(+3.3V)
Not installed
Connected to an
external supply
Powered by +3.3V from
an external supply or
SATA power connector
SHUNT
POSITION
EN PIN (U1) DESCRIPTION
1-2*
Connected to
+3.3V
Buffers enabled for
normal operation
2-3
Connected to
GND
Buffers disabled and the
device is in low-power
mode
Table 2. Jumper JU4 Function
Table 3. Jumper JU1 Function (U1 EN)