| *--------------------------------------------------------------------------- |
| * SPDX-FileCopyrightText: 2020 Efabless Corporation |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * https://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| * |
| * SPDX-License-Identifier: Apache-2.0 |
| *--------------------------------------------------------------------------- |
| * All-digital Frequency-locked loop |
| *--------------------------------------------------------------------------- |
| * To make this simulatable, the circuit is broken into the ring oscillator |
| * and controller, separately, with the controller converted into an xspice |
| * model. |
| * |
| * For simplicity, the DCO mode has been removed, so no external trim with |
| * multiplexer. Also no multiplexer on the internal reset. |
| *--------------------------------------------------------------------------- |
| |
| .include "digital_pll_controller.xspice" |
| .include "ring_osc2x13.spice" |
| |
| .subckt digital_pll vdd vss reset osc clockp1 clockp0 div4 div3 div2 div1 div0 |
| |
| X0 vdd vss clockp0 div0 div1 div2 div3 div4 osc reset trim0 trim1 trim2 trim3 |
| + trim4 trim5 trim6 trim7 trim8 trim9 trim10 trim11 trim12 trim13 trim14 |
| + trim15 trim16 trim17 trim18 trim19 trim20 trim21 trim22 trim23 trim24 |
| + trim25 digital_pll_controller |
| |
| X1 vdd vss clockp0 clockp1 reset trim0 trim1 trim2 trim3 trim4 trim5 trim6 trim7 |
| + trim8 trim9 trim10 trim11 trim12 trim13 trim14 trim15 trim16 trim17 trim18 |
| + trim19 trim20 trim21 trim22 trim23 trim24 trim25 ring_osc2x13 |
| |
| .ends |
| |
| |