IEC 61523-4:2023

IEC 61523-4 ®
Edition 2.0 2023-10
™
IEEE Std 1801
INTERNATIONAL
STANDARD
colour
inside
Delay and power calculation standards –
Part 4: Design and Verification of Low-Power, Energy-Aware Electronic Systems
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IEC 61523-4 ®
Edition 2.0 2023-10
IEEE Std 1801™
INTERNATIONAL
STANDARD
colour
inside
Delay and power calculation standards –
Part 4: Design and Verification of Low-Power, Energy-Aware Electronic Systems
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 25.040.01, 35.060 ISBN 978-2-8322-7540-5
– i – IEEE Std 1801™-2018
IEEE Std 1801-2018
IEEE Standard for Design and Verification of Low-Power, Energy-Aware Electronic Systems
Contents
1. Overview . 13
1.1 Scope . 13
1.2 Purpose . 13
1.3 Key characteristics of the Unified Power Format . 13
1.4 Contents of this standard . 15
2. Normative references . 16
3. Definitions, acronyms, and abbreviations. 16
3.1 Definitions . 16
3.2 Acronyms and abbreviations . 22
4. Concepts . 23
4.1 Introduction . 23
4.2 Design structure . 24
4.3 Design representation . 24
4.4 Power architecture . 28
4.5 Power distribution . 31
4.6 Power management . 39
4.7 Supply states and power states. 44
4.8 Simstates . 51
4.9 Power intent specification . 52
5. Language basics . 58
5.1 UPF is Tcl . 58
5.2 Conventions used . 59
5.3 Lexical elements . 61
5.4 Boolean expressions . 65
5.5 Object declaration . 67
5.6 Attributes of objects . 67
5.7 Precedence . 72
5.8 Generic UPF command semantics . 75
5.9 effective_element_list semantics . 76
5.10 Command refinement . 79
5.11 Error handling . 80
5.12 Units . 80
5.13 SystemC language basic . 80
6. Power intent commands. 81
6.1 Introduction . 81
6.2 Categories . 81
6.3 add_parameter . 82
6.4 add_port_state (legacy) . 83
6.5 add_power_state . 84
6.6 add_pst_state (legacy) . 91
6.7 add_state_transition . 92
6.8 add_supply_state . 94
6.9 apply_power_model . 95
6.10 associate_supply_set . 97
6.11 begin_power_model (legacy) . 99
6.12 bind_checker . 100

Published by IEC under licence from IEEE. © 2018 IEEE. All rights reserved.

IEEE Std 1801™-2018 – ii –
IEEE Std 1801-2018
IEEE Standard for Design and Verification of Low-Power, Energy-Aware Electronic Systems
6.13 connect_logic_net . 102
6.14 connect_supply_net . 104
6.15 connect_supply_set . 106
6.16 create_composite_domain . 107
6.17 create_hdl2upf_vct . 109
6.18 create_logic_net . 110
6.19 create_logic_port . 111
6.20 create_power_domain . 112
6.21 create_power_state_group . 119
6.22 create_power_switch . 121
6.23 create_pst (legacy) . 128
6.24 create_supply_net . 129
6.25 create_supply_port . 133
6.26 create_supply_set . 134
6.27 create_upf2hdl_vct . 136
6.28 define_power_model . 137
6.29 describe_state_transition (deprecated) . 139
6.30 end_power_model (legacy) . 139
6.31 find_objects . 140
6.32 load_simstate_behavior . 144
6.33 load_upf . 145
6.34 load_upf_protected (deprecated) . 146
6.35 map_power_switch . 146
6.36 map_repeater_cell . 147
6.37 map_retention_cell . 148
6.38 name_format . 152
6.39 save_upf . 153
6.40 set_correlated . 154
6.41 set_design_attributes . 155
6.42 set_design_top . 156
6.43 set_domain_supply_net (legacy) . 157
6.44 set_equivalent . 158
6.45 set_isolation . 160
6.46 set_level_shifter . 167
6.47 set_partial_on_translation . 173
6.48 set_port_attributes. 175
6.49 set_repeater . 181
6.50 set_retention . 185
6.51 set_retention_elements . 189
6.52 set_scope . 190
6.53 set_simstate_behavior . 191
6.54 set_variation . 194
6.55 sim_assertion_control . 195
6.56 sim_corruption_control . 197
6.57 sim_replay_control . 200
6.58 upf_version . 202
6.59 use_interface_cell . 203
7. Power-management cell definition commands . 205
7.1 Introduction . 205
7.2 define_always_on_cell . 206
7.3 define_diode_clamp . 207
7.4 define_isolation_cell . 208
7.5 define_level_shifter_cell . 211
7.6 define_power_switch_cell . 216
7.7 define_retention_cell . 218

Published by IEC under licence from IEEE. © 2018 IEEE. All rights reserved.

– iii – IEEE Std 1801™-2018
IEEE Standard for Design and Verification of Low-Power, Energy-Aware Electronic Systems
8. UPF processing . 220
8.1 Overview . 220
8.2 Data requirements . 221
8.3 Processing phases . 221
8.4 Error checking . 225
9. Simulation semantics . 225
9.1 Supply network creation . 225
9.2 Supply network simulation . 227
9.3 Power state simulation . 228
9.4 Power state transition detection . 231
9.5 Simstate simulation . 232
9.6 Transitioning from one simstate state to another . 234
9.7 Simulation of retention . 235
9.8 Simulation of isolation . 241
9.9 Simulation of level-shifting . 242
9.10 Simulation of repeaters . 242
10. UPF information model . 242
10.1 Overview . 242
10.2 Components of UPF information model . 243
10.3 Identifiers in information model (IDs) . 244
10.4 Classification of objects . 247
10.5 Example of design hierarchy . 253
10.6 Object definitions. 254
11. Information model application programmable interface (API) . 313
11.1 Tcl interface . 313
11.2 HDL interface . 323
Annex A (informative) Bibliography . 387
Annex B (normative) Value conversion tables . 388
B.1 Overview . 388
B.2 VHDL_SL2UPF . 388
B.3 UPF2VHDL_SL . 388
B.4 VHDL_SL2UPF_GNDZERO. 388
B.5 UPF_GNDZERO2VHDL_SL. 389
B.6 SV_LOGIC2UPF . 389
B.7 UPF2SV_LOGIC . 389
B.8 SV_LOGIC2UPF_GNDZERO . 389
B.9 UPF_GNDZERO2SV_LOGIC . 389
B.10 VHDL_TIED_HI . 390
B.11 SV_TIED_HI . 390
B.12 VHDL_TIED_LO . 390
B.13 SV_TIED_LO . 390
Annex C (informative) UPF query examples . 391
C.1 Overview . 391
C.2 Utility procs . 391
C.3 High-level procs . 392
C.4 Superseded UPF queries . 394
Annex D (informative) Replacing deprecated and legacy commands and options . 396
D.1 Overview. 396
D.2 Deprecated and legacy constructs . 396

Published by IEC under licence from IEEE. © 2018 IEEE. All rights reserved.

IEEE Std 1801™-2018 – iv –
IEEE Standard for Design and Verification of Low-Power, Energy-Aware Electronic Systems
D.3 Recommendations for replacing deprecated and legacy constructs . 398
Annex E (informative) Low-power design methodology . 401
E.1 Overview . 401
E.2 Simple System on Chip (SoC) example design . 401
E.3 Design, verification, and implementation flow . 404
E.4 Power intent of the example design . 407
Annex F (informative) Power-management cell definitions in UPF and Liberty . 428
F.1 Introduction . 428
F.2 define_always_on_cell . 428
F.3 define_diode_clamp . 430
F.4 define_isolation_cell. 431
F.5 define_level_shifter_cell . 434
F.6 define_power_switch_cell . 436
F.7 define_retention_cell . 438
Annex G (informative) Power-management cell modeling examples . 442
G.1 Overview. 442
G.2 Modeling always-on cells . 442
G.3 Modeling cells with internal diodes . 448
G.4 Modeling isolation cells . 450
G.5 Modeling level-shifters . 467
G.6 Modeling power-switch cells . 484
G.7 Modeling state retention cells . 494
Annex H (informative) IP power modeling for system-level design . 506
H.1 Introduction. 506
H.2 Overview of system-level IP power models . 506
H.3 Content of system-level IP power models . 507
H.4 Power calculation using power functions . 508
H.5 Power model structure . 510
H.6 Power model instantiation—example approach . 511
Annex I (normative) Switching Activity Interchange Format . 513
I.1 Syntactic conventions . 514
I.2 Lexical conventions . 515
I.3 Backward SAIF file . 518
I.4 Library forward SAIF file . 534
I.5 RTL forward SAIF file . 542
Annex J (informative) Participants . 547

Published by IEC under licence from IEEE. © 2018 IEEE. All rights reserved.

– v – IEEE Std 1801™-2018
DELAY AND POWER CALCULATION STANDARDS –
Part 4: Design and Verification of Low-Power, Energy-Aware Electronic
Systems
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IEEE Std 1801™-2018 – vi –
IEC 61523-4/IEEE Std 1801 was processed through IEC technical committee 91: Electronics
assembly technology, under the IEC/IEEE Dual Logo Agreement. It is an International
Standard.
The text of this International Standard is based on the following documents:
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1801 (2018) 91/1870/FDIS 91/1884/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
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IEEE Std 1801™-2018
IEEE Standard for Design and
Verification of Low-Power, Energy-
Aware Electronic Systems
Sponsor
Design Automation Standards Committee
of the
IEEE Computer Society
Approved 27 September 2018
IEEE-SA Standards Board
Published by IEC under licence from IEEE. © 2018 IEEE. All rights reserved.

IEEE Std 1801™-2018
Abstract: A method is provided for specifying power intent for an electronic design, for use in
verification of the structure and behavior of the design in the context of a given power-
management architecture, and for driving implementation of that power-management
architecture. The method supports incremental refinement of power intent specifications required
for IP-based design flows.
Keywords: corruption semantics, IEEE 1801™, interface specification, IP reuse, isolation,
level-shifting, power-aware design, power domains, power intent, power modes, power states,
progressive design refinement, retention, retention strategies
•
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IEEE Std 1801™-2018
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IEEE Std 1801™-2018
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