JAJSHR0E March 2017 – July 2022 LMH1297
PRODUCTION DATA
PIN | I/O(1) | DESCRIPTION | |
---|---|---|---|
NAME | NO. | ||
HIGH-SPEED DIFFERENTIAL I/OS | |||
SDI_IO+ | 1 | I/O, Analog | Single-ended complementary inputs or outputs with
on-chip 75-Ω termination at SDI_IO+ and SDI_IO–. SDI_IO± include
integrated return loss networks designed to meet the SMPTE input and
output return loss requirements. Connect SDI_IO+ to a BNC through a
4.7-µF, AC-coupling capacitor. SDI_IO– should be similarly
AC-coupled and terminated with an external 4.7-µF capacitor and 75-Ω
resistor to GND. EQ mode: SDI_IO+ is the 75-Ω input port of the adaptive cable equalizer for SMPTE video applications. CD mode: SDI_IO+ is the 75-Ω output port of the cable driver for SMPTE video applications. |
SDI_IO– | 2 | I/O, Analog | |
SDI_OUT– | 7 | O, Analog | Single-ended complementary outputs with on-chip 75-Ω
termination at SDI_OUT+ and SDI_OUT–. SDI_OUT± include integrated
return loss networks designed to meet the SMPTE output return loss
requirements. SDI_OUT± is used as a second cable driver. Connect
SDI_OUT+ to a BNC through a 4.7-µF, AC-coupling capacitor. SDI_OUT–
should be similarly AC-coupled and terminated with an external
4.7-µF capacitor and 75-Ω resistor to GND. EQ mode: SDI_OUT± can be enabled as a loop-through 75-Ω output port. It outputs the reclocked data from the adaptive cable equalizer to form a loop-through output with adaptive cable equalizer, reclocker, and cable driver. CD mode: SDI_OUT± is the second 75-Ω fan-out cable driver. |
SDI_OUT+ | 8 | O, Analog | |
IN0– | 18 | I, Analog | Differential inputs from host video processor. On-chip 100-Ω differential termination. Requires external 4.7-µF, AC-coupling capacitors for SMPTE applications. |
IN0+ | 19 | I, Analog | |
OUT0– | 22 | O, Analog | Differential outputs to host video processor. On-chip 100-Ω differential termination. Requires external 4.7-µF, AC-coupling capacitors for SMPTE applications. |
OUT0+ | 23 | O, Analog | |
CONTROL PINS | |||
OUT0_SEL | 4 | I, LVCMOS | OUT0_SEL enables the use of the 100-Ω host-side output driver at
OUT0±. See Table 8-3 for details. OUT0_SEL is internally pulled high by default (OUT0 disabled). |
EQ/CD_SEL | 5 | I, LVCMOS | EQ/CD_SEL selects the signal direction of the LMH1297 bidirectional
I/O. It configures the LMH1297 as an adaptive equalizer (EQ mode) or
as a cable driver (CD mode). See Table 8-2 for details. EQ/CD_SEL is internally pulled low by default (EQ mode). |
HOST_EQ0 | 9 | I, 4-LEVEL | HOST_EQ0 selects the driver output amplitude and de-emphasis level
for OUT0± (in EQ mode) and equalizer setting for IN0± (in CD mode).
See Table 8-5 and Table 8-10 for details. |
MODE_SEL | 12 | I, 4-LEVEL | MODE_SEL enables the SPI or SMBus serial control interface. See Table 8-11 for details. |
SDI_OUT_SEL | 14 | I, LVCMOS | SDI_OUT_SEL enables the use of the 75-Ω output driver at SDI_OUT±.
See Table 8-3 for details. SDI_OUT_SEL is internally pulled high by default (SDI_OUT disabled). |
OUT_CTRL | 17 | I, 4-LEVEL | OUT_CTRL selects the signal being routed to the output. It is used
to enable or bypass the reclocker and to enable or bypass the cable
equalizer. See Table 8-7 for details. |
SDI_VOD | 24 | I, 4-LEVEL | SDI_VOD selects one of four output amplitudes for the cable drivers
at SDI_IO± and SDI_OUT±. See Table 8-8 for details. |
LOCK_N | 27 | O, LVCMOS, OD |
LOCK_N is the reclocker lock indicator. LOCK_N is pulled low when
the reclocker has acquired lock condition. LOCK_N is a 3.3-V
tolerant, open-drain output. It requires an external resistor to a
logic supply. LOCK_N can be reconfigured to indicate Carrier Detector (CD_N) or Interrupt (INT_N) through register programming. See Section 8.3.10. |
ENABLE | 32 | I, LVCMOS | A
logic-high at ENABLE enables normal operation for the LMH1297. A
logic-low at ENABLE places the LMH1297 in Power-Down mode. ENABLE is internally pulled high by default. |
SPI SERIAL CONTROL INTERFACE, MODE_SEL = F (FLOAT) | |||
SS_N | 11 | I, LVCMOS | SS_N is the Target Select. When SS_N is at logic Low, it enables SPI
access to the LMH1297 target device. SS_N is a 2.5-V LVCMOS input and is internally pulled high by default. |
MOSI | 13 | I, LVCMOS | MOSI is the SPI serial control data input to the LMH1297 target device when the SPI bus is enabled. MOSI is a 2.5-V LVCMOS input.
An external pullup resistor is recommended. |
MISO | 28 | O, LVCMOS | MISO is the SPI serial control data output from the LMH1297 target device. MISO is a 2.5-V LVCMOS output. |
SCK | 29 | I, LVCMOS | SCK is the SPI serial input clock to the LMH1297 target device when
the SPI interface is enabled. SCK is a 2.5-V LVCMOS input. An external pullup resistor is recommended. |
SMBUS SERIAL CONTROL INTERFACE, MODE_SEL = L (1 KΩ TO VSS) | |||
ADDR0 | 11 | Strap, 4-LEVEL | ADDR[1:0] are 4-level straps, read into the device at power up. They are used to select one of the 16 supported SMBus addresses when SMBus is enabled. See Table 8-12 for details. |
SDA | 13 | I/O, LVCMOS, OD |
SDA is the SMBus bidirectional data line to or from the LMH1297 target device when SMBus is enabled. SDA is an open-drain I/O and requires an external pullup resistor to the SMBus termination voltage. SDA is 3.3-V tolerant. |
ADDR1 | 28 | Strap, 4-LEVEL | ADDR[1:0] are 4-level straps, read into the device at power up. They are used to select one of the 16 supported SMBus addresses when SMBus is enabled. See Table 8-12 for details. |
SCL | 29 | I/O, LVCMOS, OD |
SCL is the SMBus input clock to the LMH1297 target device when SMBus is enabled. It is driven by a LVCMOS open-drain driver from the SMBus controller. SCL requires an external pullup resistor to the SMBus termination voltage. SCL is 3.3-V tolerant. |
RESERVED | |||
RSV1 RSV2 RSV3 RSV4 RSV5 |
10 15 16 25 26 |
— | Reserved pins. Do not connect. |
POWER | |||
VSS | 3, 6, 20 | I, Ground | Ground reference. |
VDD_CDR | 21 | I, Power | VDD_CDR powers the reclocker circuitry. It is connected to the same 2.5-V ± 5% supply as VIN. |
VIN | 30 | I, Power | VIN is connected to an external 2.5-V ± 5% power supply. |
VDD_LDO | 31 | O, Power | VDD_LDO is the output of the internal 1.8-V LDO regulator. VDD_LDO output requires an external 1-µF and 0.1-µF bypass capacitor to VSS. The internal LDO is designed to power internal circuitry only. |
EP | — | I, Ground | EP is the exposed pad at the bottom of the RTV package. The exposed pad should be connected to the VSS plane through a 3 × 3 via array. |