e7804 Semtech Corporation, e7804 Datasheet - Page 18

• Manufacturer Part Number: e7804
• Description: 133 Mhz Quad Pin Electronics Driver And Window Comparator
• Manufacturer: Semtech Corporation

©
TEST AND MEASUREMENT PRODUCTS
Circuit Description (continued)
2007 Semtech Corp. / Rev. 7, 02/26/07
Channel Functions
Channel Relay and States Registers
Register Name CH0_switches_&_states
Default Value
Description
Register Name CH1_switches_&_states
Default Value
Description
Register Name CH2_switches_&_states
Default Value
Description
Register Name
Default Value
Description
0 0000 0000 0000
This register is used for controlling the Channel_0 (CH0) switches. Bits are also present to control the CH0 driver state and read
back the states of the CH0 comparator outputs. The comparator output states are indicated above as unknown unless the input
voltage relationships are known.
D0 – S1 – writing a one to this bit will close the switch that connects the driver output to the channels VIO pin.
D1 – S2 – writing a one to this bit will close the switch that connects the window comparator input to the channel's VIO pin.
D2 – S3 – writing a one to this bit will close the switch that connects the driver output to the external PMU sense line (EPMUS) for
purposes of system diagnostics.
D3 – S4 – writing a one to this bit will close the switches that connect both the external PMU bus sense (EPMUS) and force
(EPMUF) lines to the channel's POUT pin.
D4 – S5 – writing a one to this bit will close the switch that connects the continuity test circuit (CTC) to the channel's POUT pin. If
any channel has S5 closed, then output impedance calibration cannot occur.
D5 – S6 – writing a one to this bit will close the switch that connects the pull-up resistor and voltage to the channel's POUT pin.
D6 – SDHI (Serial Data Hi) – writing a logical one to this bit will force the channel's driver to output the DVH voltage. Writing a zero
to this bit will force the driver to output the DVL voltage. The SDHI bit will only have effect if the SEN bit (D8) in this register is set to
a logical one, allowing the SDHI bit to override the state of the external DHI signal to this channel's driver.
D7 – SDEN (Serial Data Enable) – writing a logical one to this bit will enable the channel's driver to output either DVH or DVL (based
on the SDHI bit). Writing a zero to this bit disables the driver output to high impedance. The SDEN bit will only have effect if the
SEN bit (D8) in this register is set to a logical 1, allowing the SDEN bit to override the state of the external DEN signal to this
channel's driver.
D8 – SEN (Serial Enable) – writing this bit to a logical one will allow the D6 and D7 bits in this register override the external driver
control signals DHI and DEN.
D9 – QB – this bit is a Read Only bit that is the state of the channel's comparator B output. Writing to this bit will have no effect.
D10 – QA – this bit is a Read Only bit that is the state of the channel's comparator A output. Writing to this bit will have no effect.
0 0000 0000 0000
This register is used for controlling the Channel_1 (CH1) switches. Bits are also present to control the CH1 driver state and read
back the states of the CH1 comparator outputs. See the bit definitions above for the CH0_relay_&_switches register.
0 0000 0000 0000
This register is used for controlling the Channel 2 (CH2) switches. Bits are also present to control the CH2 driver state and read
back the states of the CH2 comparator outputs. See the bit definitions above for the CH0_relay_&_switches register.
CH3_switches_&_states
0 0000 0000 0000
This register is used for controlling the Channel 3 (CH3) switches. Bits are also present to control the CH3 driver state and read
back the states of the CH3 comparator outputs. See the bit definitions above for the CH0_relay_&_switches register.
Function Address
Channel/Set Address 0x00
Channel Select Bit
0x00
Function Address
Channel/Set Address 0x01
Channel Select Bit
0x00
Function Address
Channel/Set Address 0x02
Channel Select Bit
Function Address
Channel/Set Address 0x03
Channel Select Bit
0x00
8
0x00
1
0x00
1
0x00
1
0x00
1
Set Select Bit
Mode
Set Select Bit
Mode
Set Select Bit
Mode
Set Select Bit
Mode
0
Read/Write
0
Read/Write
0
Read/Write
0
Read/Write
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