44 lines
1.2 KiB
Plaintext
44 lines
1.2 KiB
Plaintext
ADDER - 4 BIT ALL-74HC00-GATE BINARY ADDER WITH AUTOMATIC BRIDGING
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* behavioral gate description
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* Automatic A/D insertion using bi-directional bridges
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* The NAND gates in the adder have a "family" parameter that determines
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* the A/D and D/A bridges that are inserted. For A/D a subcircuit is
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* used, defined by the file bridge_demo_family_d_in.subcir. For D/A
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* the following interpreter variable sets up the bridges with non-default
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* output levels.
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.control
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pre_set auto_bridge_demo_family_d_out =
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+ ( ".model auto_da dac_bridge(out_high='%g-0.7' out_low=0.9 )"
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+ "auto_bridge%d [ %s ] [ %s ] auto_da" 1000 )
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.endc
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.param vcc=5 tripdt=6n
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*
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* 2-input NAND gate
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* vcc 2 /4.5/5 /6
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* tpd 25n/9n/7n/7n
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* tr 19n/7n / /6n
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*** Subcircuit definition: copy of 74HCng_auto.lib with "family" parameter
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.SUBCKT 74HC00 in1 in2 out NVCC NVGND vcc1={vcc} tripdt1={tripdt}
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.param td1={1e-9*(9-3-3)*4.0/(vcc1-0.5)}
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.param Rout={60*4.0/(vcc1-0.5)} ; standard output driver
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a6 [in1 in2] dout nand1
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.model nand1 d_nand(rise_delay = {td1} fall_delay = {td1}
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+ input_load = 0.5e-12) family="demo_family"
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Rout dout out {Rout}
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.ends
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.param vcc=3 tripdt=6n
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.include ../adder_common.inc
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.END
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