Sky130 Bandgap

Bandgap voltage reference on sky130 — 2AM Logic canary block

sky130-bandgap

Source: 2AMLogic/sky130-bandgap @ 7d1ce0516877

Specification

ratified — see [DR-005](spec/decision-records/DR-005-ratify-target-spec.md

Output reference	1.20 V ±2% untrimmed (3σ, mismatch MC N≥300 + process corners, −40…125 °C) · stretch: ±0.5% trimmed (3σ, 1-point trim)
Trim	1-point resistor trim (binary-weighted segments, `res_high_po`), range ≥ ±5%, resolution ≤ 0.25%/step (≥5 bits equiv.), magnitude only, at 27 °C
Temp coefficient (−40…125 °C)	< 50 ppm/°C (box method) · stretch: < 20 ppm/°C (curvature correction)
PSRR	> 60 dB DC–1 kHz · stretch: > 30 dB @ 1 MHz
Supply	3.3 V ±10% · stretch: 1.8 V-core Banba variant
Iq	< 50 µA · stretch: < 20 µA
Area	< 0.08 mm² (DR-007; relaxed from 0.05 to fit the drawn `MCC` cap)
Startup	self-starting, < 1 ms

Schematic

Source: 2AMLogic/sky130-bandgap @ 31d8167 (design/bandgap_core.sch).

Renders

Click a render to open an interactive, pan/zoom viewer of the actual GDS.

Overview render of Sky130 Bandgap — Overview

diff.drawing render of Sky130 Bandgap — diff.drawing

Layer 64/20 render of Sky130 Bandgap — Layer 64/20

Layer 66/13 render of Sky130 Bandgap — Layer 66/13

Layer 68/5 render of Sky130 Bandgap — Layer 68/5

Layer 83/20 render of Sky130 Bandgap — Layer 83/20

Layer 86/20 render of Sky130 Bandgap — Layer 86/20

Layer 94/20 render of Sky130 Bandgap — Layer 94/20

li1.drawing render of Sky130 Bandgap — li1.drawing

licon1.drawing render of Sky130 Bandgap — licon1.drawing

mcon.drawing render of Sky130 Bandgap — mcon.drawing

met1.drawing render of Sky130 Bandgap — met1.drawing

met2.drawing render of Sky130 Bandgap — met2.drawing

pnp.drawing render of Sky130 Bandgap — pnp.drawing

poly.drawing render of Sky130 Bandgap — poly.drawing

tap.drawing render of Sky130 Bandgap — tap.drawing

via.drawing render of Sky130 Bandgap — via.drawing

Zoomed crop render of Sky130 Bandgap — Zoomed crop

Metrics

Layers	16
Cells	27
Instances	26

Signals

Corner	Status	Measurement	Value	Margin
bandgap-smoke/tt_27c_3.30v	pass	vref	1.20 V	—
bandgap-smoke/tt_27c_3.30v	pass	vos_loop	8.68 µV	—
bandgap-smoke/tt_27c_3.30v	pass	vgdrv	2.04 V	—
bandgap-smoke/tt_27c_3.30v	pass	vbe_ctat	731.17 mV	—
bandgap-smoke/tt_27c_3.30v	pass	dvbe	62.35 mV	—
bandgap-smoke/tt_27c_3.30v	pass	isup	31.16 µA	—
error-amp-loop/tt_27c_2.97v	pass	vref_delta	33.30 pV	—
error-amp-loop/tt_27c_2.97v	pass	iq_delta	0.58 fA	—
error-amp-loop/tt_27c_2.97v	pass	iq_total	31.14 µA	—
error-amp-loop/tt_27c_2.97v	pass	iq_amp	20.51 µA	—
error-amp-loop/tt_27c_2.97v	pass	iq_core	10.64 µA	—
error-amp-loop/tt_27c_2.97v	pass	loop_gain_dc	50.49 dB	—
error-amp-loop/tt_27c_2.97v	pass	ugf	220.18 kHz	—
error-amp-loop/tt_27c_2.97v	pass	phase_margin	62.98 deg	—
error-amp-offset-mc/overall	pass	No measurements.
line-regulation/tt_27c_3.30v	pass	line_shift_mv	10.33 mmV	—
line-regulation/tt_27c_3.30v	pass	line_reg_pct_per_v	1.34 m%/V	—
line-regulation/tt_27c_3.30v	pass	line_psrr_db	96.11 dB	—
line-regulation/tt_27c_3.30v	pass	vref_nom	1.17 V	—
line-regulation/tt_27c_3.30v	pass	sweep_start_v	2.97 V	—
line-regulation/tt_27c_3.30v	pass	sweep_end_v	3.63 V	—
line-regulation/tt_27c_3.30v	pass	n_supply_points	31.00	—
line-regulation-post-layout/tt_27c_3.30v	pass	line_shift_mv	18.55 mmV	—
line-regulation-post-layout/tt_27c_3.30v	pass	line_reg_pct_per_v	2.35 m%/V	—
line-regulation-post-layout/tt_27c_3.30v	pass	line_psrr_db	91.03 dB	—
line-regulation-post-layout/tt_27c_3.30v	pass	vref_nom	1.19 V	—
line-regulation-post-layout/tt_27c_3.30v	pass	sweep_start_v	2.97 V	—
line-regulation-post-layout/tt_27c_3.30v	pass	sweep_end_v	3.63 V	—
line-regulation-post-layout/tt_27c_3.30v	pass	n_supply_points	31.00	—
monte-carlo-untrimmed/overall	fail	No measurements.
mos-matching-characterization/tt_27c_3.30v	pass	mna2u_id	2.00 µA	—
mos-matching-characterization/tt_27c_3.30v	pass	mna2u_vth	811.89 mV	—
mos-matching-characterization/tt_27c_3.30v	pass	mna2u_vov	50.69 mV	—
mos-matching-characterization/tt_27c_3.30v	pass	mna2u_gmid	15.39 /V	—
mos-matching-characterization/tt_27c_3.30v	pass	mna5u_id	5.00 µA	—
mos-matching-characterization/tt_27c_3.30v	pass	mna5u_vth	811.93 mV	—
mos-matching-characterization/tt_27c_3.30v	pass	mna5u_vov	118.05 mV	—
mos-matching-characterization/tt_27c_3.30v	pass	mna5u_gmid	11.73 /V	—
mos-mirror-sizing-extended/tt_27c_3.30v	pass	mnb_id	5.30 µA	—
mos-mirror-sizing-extended/tt_27c_3.30v	pass	mnb_vth	797.42 mV	—
mos-mirror-sizing-extended/tt_27c_3.30v	pass	mnb_vov	141.53 mV	—
mos-mirror-sizing-extended/tt_27c_3.30v	pass	mnb_gmid	10.84 /V	—
mos-mirror-sizing-extended/tt_27c_3.30v	pass	mnc_id	5.30 µA	—
mos-mirror-sizing-extended/tt_27c_3.30v	pass	mnc_vth	799.46 mV	—
mos-mirror-sizing-extended/tt_27c_3.30v	pass	mnc_vov	138.99 mV	—
mos-mirror-sizing-extended/tt_27c_3.30v	pass	mnc_gmid	10.94 /V	—
output-voltage-tc/overall	fail	No measurements.
output-voltage-tc-post-layout/overall	fail	No measurements.
pdk-smoke/tt_27c_2.97v	pass	vgs	918.85 mV	—
pdk-smoke/tt_27c_2.97v	pass	isup	2.05 µA	—
pnp-characterization/tt_27c_3.30v	pass	veb_small_100n	679.83 mV	—
pnp-characterization/tt_27c_3.30v	pass	veb_large_100n	619.31 mV	—
pnp-characterization/tt_27c_3.30v	pass	dvbe_100n	60.52 mV	—
pnp-characterization/tt_27c_3.30v	pass	veb_small_316n	710.92 mV	—
pnp-characterization/tt_27c_3.30v	pass	veb_large_316n	649.42 mV	—
pnp-characterization/tt_27c_3.30v	pass	dvbe_316n	61.50 mV	—
pnp-characterization/tt_27c_3.30v	pass	veb_small_1u	742.54 mV	—
pnp-characterization/tt_27c_3.30v	pass	veb_large_1u	679.57 mV	—
pnp-mismatch/overall	pass	No measurements.
psrr-dc/tt_27c_2.97v	pass	psrr_dc	91.56 dB	—
psrr-dc/tt_27c_2.97v	pass	f_dc	100.00 mHz	—
psrr-dc/tt_27c_2.97v	pass	psrr_1k	62.99 dB	—
psrr-dc/tt_27c_2.97v	pass	f_1k	1.00 kHz	—
psrr-dc/tt_27c_2.97v	pass	psrr_band_min	62.99 dB	—
psrr-dc/tt_27c_2.97v	pass	psrr_1m	10.77 dB	—
psrr-dc/tt_27c_2.97v	pass	f_1m	1.00 MHz	—
psrr-dc/tt_27c_2.97v	pass	n_ac_points	71.00	—
psrr-dc-post-layout/tt_125c_3.63v	pass	psrr_dc	82.72 dB	—
psrr-dc-post-layout/tt_125c_3.63v	pass	f_dc	100.00 mHz	—
psrr-dc-post-layout/tt_125c_3.63v	pass	psrr_1k	60.35 dB	—
psrr-dc-post-layout/tt_125c_3.63v	pass	f_1k	1.00 kHz	—
psrr-dc-post-layout/tt_125c_3.63v	pass	psrr_band_min	60.35 dB	—
psrr-dc-post-layout/tt_125c_3.63v	pass	psrr_1m	9.11 dB	—
psrr-dc-post-layout/tt_125c_3.63v	pass	f_1m	1.00 MHz	—
psrr-dc-post-layout/tt_125c_3.63v	pass	n_ac_points	71.00	—
quiescent-current/tt_27c_2.97v	pass	iq	31.14 µA	—
quiescent-current/tt_27c_2.97v	pass	vref	1.20 V	—
quiescent-current/tt_27c_2.97v	pass	vgdrv	1.71 V	—
quiescent-current-post-layout/tt_27c_2.97v	pass	iq	19.99 µA	—
quiescent-current-post-layout/tt_27c_2.97v	pass	vref	1.19 V	—
quiescent-current-post-layout/tt_27c_2.97v	pass	vgdrv	1.76 V	—
res-array-head-resistance/overall	fail	No measurements.
res-array-resize/overall	pass	No measurements.
resistor-flavor-characterization/tt_27c_3.30v	pass	r_highl1	704.53 ohm	—
resistor-flavor-characterization/tt_27c_3.30v	pass	r_highl20	6.88 kohm	—
resistor-flavor-characterization/tt_27c_3.30v	pass	r_xhighl1	2.15 kohm	—
resistor-flavor-characterization/tt_27c_3.30v	pass	r_xhighl20	42.41 kohm	—
resistor-tc-single-length/tt_27c_3.30v	pass	r_xh_l50_5u	105.97 kohm	—
resistor-tc-single-length/tt_27c_3.30v	pass	r_xh_l50_0p5u	105.97 kohm	—
resistor-tc-single-length/tt_27c_3.30v	pass	r_xh_l5_5u	10.63 kohm	—
resistor-tc-single-length/tt_27c_3.30v	pass	r_high_l50_5u	16.62 kohm	—
resistor-tc-single-length/tt_27c_3.30v	pass	tc_probe_lit	997.07 ohm	—
resistor-tc-single-length/tt_27c_3.30v	pass	tc_probe_expr	997.07 ohm	—
resistor-tc-single-length/tt_27c_3.30v	pass	tc_probe_beh	1.00 kohm	—
startup-ramp/tt_-40c_2.97v	pass	t_start_s	-372.72 µs	—
startup-ramp/tt_-40c_2.97v	pass	t_start_f	-113.24 ns	—
startup-ramp/tt_-40c_2.97v	pass	t_start_g	1.11 ns	—
startup-ramp/tt_-40c_2.97v	pass	t_abs_s	603.71 µs	—
startup-ramp/tt_-40c_2.97v	pass	vref_s	1.21 V	—
startup-ramp/tt_-40c_2.97v	pass	vref_f	1.21 V	—
startup-ramp/tt_-40c_2.97v	pass	vref_g	1.21 V	—
startup-ramp/tt_-40c_2.97v	pass	vref_spread	479.00 µV	—
startup-stability/tt_-40c_2.97v	pass	ncross_su	1.00	—
startup-stability/tt_-40c_2.97v	pass	alpha_eq	553.78 m	—
startup-stability/tt_-40c_2.97v	pass	itrav_min	306.14 µA	—
startup-stability/tt_-40c_2.97v	pass	imin_off_su	679.71 µA	—
startup-stability/tt_-40c_2.97v	pass	imin_off_bare	11.59 pA	—
startup-stability/tt_-40c_2.97v	pass	i_off_su	693.17 µA	—
startup-stability/tt_-40c_2.97v	pass	i_off_bare	75.83 pA	—
startup-stability/tt_-40c_2.97v	pass	i_on_su	-825.10 µA	—
startup-time/overall	fail	No measurements.
startup-time-post-layout/overall	fail	No measurements.
trim-lsb-chained/overall	fail	No measurements.
trim-range-monotonicity/overall	pass	No measurements.

Field Data

Provenance

Solver	github.com/rjwalters/geode-fem v0.3.0 @ 90759f103fdb · release
Backend	burn::backend::NdArray<f64, i32> (CPU; no GPU feature compiled -- see geode-core's testing::TestBackend cfg fallback)
Geometry	A real routed bundle of the `sky130-bandgap` gallery block: the 5 met1 nets (TAIL, net_8, net_7, D2, D1) that run parallel along x for 182.50 um (x = 24.00 .. 206.50 um), read out of the block's own committed GDS -- the same layout the gallery renders, not a benchmark shape. Widths and spacings are the drawn ones (the mesh is breakpoint-aligned to every conductor edge); net names are the GDS's own label texts.blocks/sky130-bandgap/output/bandgap_core_routed.gds · sha256 f2ff80dafb26…
Source	github.com/2AMLogic/klayout-tools @ a6f85a55f5b7 · block sky130-bandgap
Solve parameters	Run Axis: x Cross Section Axis: y Cut Position Um: 115.25 Run Start Um: 24 Run End Um: 206.5 Length Um: 182.5 Metal Bottom Um: 1.3761 Thickness Um: 0.36 Stackup Source: installed-pdk Stackup Source File: sky130A/libs.tech/magic/sky130A.tech (height allm1) Eps R: 4 Eps R Note: Typical inter-metal SiO2 dielectric (approximate, uniform -- a single permittivity everywhere, not the PDK's layered stack). Side Margin Um: 2 Top Margin Um: 1.5 Step Um: 0.12 N Nodes: 30653 N Tets: 151200 Boundary: Substrate plane (z = 0), box top and both side walls are the grounded return conductor; the run-axis ends are natural (Neumann), so the finite-length result approximates a per-length quantity away from the ends.
Generated	2026-08-14T09:18:59Z

This field result is produced by geode-fem, validated against known answers in the gallery’s solver validation strip.

Downloads

Layout (bandgap_core_routed.gds)