LMH2190 Datasheet, PDF (24/32 Pages) National Semiconductor (TI) – Quad Channel 27 MHz Clock Tree Driver with I2C Interface

LMH2190
SNAS473H – JUNE 2009 – REVISED MAY 2013
www.ti.com
Table 6. CLK4 Output Register⁽¹⁾
Field
CLK4 Load
CLK_REQ4 Input Polarity
CLK_REQ4 Force ON Control
CLK_REQ4 Force OFF Control
CLK_REQ4 Pull down Resistor
Reserved
Reserved
Bits
[1-0]
[2]
[3]
[4]
[5]
[6]
[7]
Description
Sets the drive strength of the clock output
based on the capacitive load.
00 - 10pF to 15pF
01 - 15pF to 22.5pF
10 - 22.5pF to 33.5pF
11 - 33.5pF to 50pF
Sets whether a logic low or high enables the
clock output.
0 - Logic low enables the clock output.
1 - Logic high enables the clock output.
Selects whether to use a clock request or
I²C logic to enable the output.
0 - Use the clock request pin to control
the output.
1 - Force the clock output to be enabled
(Force ON).
Selects whether to use a clock request or
I²C logic to disable the output.
0 - Use the clock request pin to control
the output.
1 - Force the clock output to be disabled
(Force OFF). ”Force OFF" overrides ”Force
ON".
Selects whether an internal 200 kΩ pull
down resistor on the clock request input to
GND is present.
0 - No internal pull down resistor is
present.
1 - Internal 200 kΩ pull-down resistor is
present.
(1) Address = 04H, type = R/W, reset value = 06H, 0000_0110, Bold face settings are the default configuration.
Field
Thermal Shutdown (TSD)
CLK_REQ1 Input Value
CLK_REQ2 Input Value
CLK_REQ3 Input Value
CLK_REQ4 Input Value
SCLK_REQ Output Value
Reserved
Table 7. Status Register⁽¹⁾
Bits
Description
[0]
Indicates if a thermal shutdown event has occurred.
0 - Thermal shutdown has not occurred.
1 - Thermal shutdown has occurred
[1]
Captures the state of the generated clock request
input value.
0 - Generated clock request is low.
1 - Generated clock request is high.
[2]
Captures the state of the generated clock request
input value.
0 - Generated clock request is low.
1 - Generated clock request is high.
[3]
Captures the state of the generated clock request
input value.
0 - Generated clock request is low.
1 - Generated clock request is high.
[4]
Captures the state of the generated clock request
input value.
0 - Generated clock request is low.
1 - Generated clock request is high.
[5]
Captures the state of the system clock request output
value.
0 - System clock request is low.
1 - System clock request is high.
[6]
(1) Address = 05H, type = R
24
Submit Documentation Feedback
Product Folder Links: LMH2190
Copyright © 2009–2013, Texas Instruments Incorporated