Who

Carsten Wulff

Why

Example of a PTAT, and a stable current bias source

How

PTAT is based on traditional bandgap structure

Stable current with temperature is based on Banba

What

What	Cell/Name
Schematic PTAT	design/JNW_BIAS_SKY130A/JNW_BIAS.sch
Layout PTAT	design/JNW_BIAS_SKY130A/JNW_BIAS.mag
Schematic Stable	design/JNW_BIAS_SKY130A/JNW_BIAS_IBS.sch
Layout Stable	design/JNW_BIAS_SKY130A/JNW_BIAS_IBS.mag

Key parameters

Parameter	Min	Typ	Max	Unit
Technology		Skywater 130 nm
AVDD	1.7	1.8	1.9	V
Temperature	-40	27	125	C

JNW_BIAS

Current proportional to temperature

Signal interface

Signal	Direction	Domain	Description
VDD_1V8	Input	VDD_1V8	Main supply
STARTUP_1V8	Input	VDD_1V8	Injects current into PMOS current mirror when active
IBP_1U[3:0]	Input	VDD_1V8	PTAT bias currents (approx 1 uA)
VSS	Input	Ground

JNW_BIAS_IBS

Current stable with temperature

Signal interface

Signal	Direction	Domain	Description
VDD_1V8	Input	VDD_1V8	Main supply
STARTUP_1V8	Input	VDD_1V8	Injects current into PMOS current mirror when active
IBPS_1U[3:0]	Input	VDD_1V8	Stable bias currents (approx 1 uA)
VSS	Input	Ground