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Bulk-driven Current Mirror

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jason_bill

jason_bill

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Hi

i want to simulate this structure :

PIC1.jpg

so i write this Net list:
Code: 
.param	Ibias1=.3m
.param	v1=.8v
.param	v5=.4v
*+++++++++++++++++++++++++++++++++++++++++++++++++++++++*
VDD	1	0	DC	v1
VG	2	0	DC	0
VB	5	0	DC	v5	
IDSS1	3	0	50U
IDSS2	7	0	50U
Iin1	33	0 	Ibias1
*+++++++++++++++++++++++++++++++++++++++++++++++++++++++*
M1	4	2	1	3	P_LV_18_MM	l=.2u w=3u	
M2	3	2	4	5	P_LV_18_MM	l=.2u w=6u	
M3	6	2	1	3	P_LV_18_MM	l=.2u w=3u	
M4	7	2	6	5	P_LV_18_MM	l=.2u w=6u	
*+++++++++++++++++++++++++++++++++++++++++++++++++++++++*
RL1	7	0	1k
Rin	3	33	0
*+++++++++++++++++++++++++++++++++++++++++++++++++++++++*
.OP
.dc	sweep 	Ibias1	0u	200u	5u
.probe	i(RL1)
.probe	i(Rin)
*+++++++++++++++++++++++++++++++++++++++++++++++++++++++*
.END

but after simulation the result isn't expectation result.

this is the output:
PIC5.gif

the expected result is like this:
PIC2.jpg

i try to simulate simple architecture of bulk driven like this:
PIC3.jpg
so i write this net list for simulation:

Code: 
.param	Ibias1=400u
.param	v1=.8v
.param	v5=.8v
*+++++++++++++++++++++++++++++++++++++++++++++++++++++++*
VDD	1	0	DC	v1
VG	2	0	DC	.5
vss	ss	0	dc	0
IDSS1	3	ss	10U
IDSS2	4	ss	10U
Iin1	33	ss	Ibias1
*+++++++++++++++++++++++++++++++++++++++++++++++++++++++*
M1	3	2	1	3	P_LV_18_MM	l=.2u w=6u	
M2	4	2	1	3	P_LV_18_MM	l=.2u w=6u		
*+++++++++++++++++++++++++++++++++++++++++++++++++++++++*
RL1	4	ss	1K
Rin	3	33	0
*+++++++++++++++++++++++++++++++++++++++++++++++++++++++*
.OP
.dc	sweep 	Ibias1	0u	100u	5u
.probe	i(RL1)
.probe	i(Rin)
*+++++++++++++++++++++++++++++++++++++++++++++++++++++++*
.END

this is the result after simulation:
PIC4.gif

while the expected result is like this:
PIC6.jpg

so what do you think? where is my mistake in simulation and Net list?

Thanks
 

I think your current sources Iin1, IDSS1 & IDSS2 source current, but they should sink it, i.e. they should be reversed. Check the bulk voltages at nodes 3 & 5 !
 

thanks dear erikl,

i check the connection of current sources and my connection was true,

this is the output of hspice when the ibias=180uA:
Code: 
 model    0:p_lv_18_ 0:p_lv_18_ 0:p_lv_18_ 0:p_lv_18_
 region       Linear   Saturati     Linear   Saturati
  id      -163.3775u -163.3769u -163.1870u -163.1864u
  ibs       -8.3109u   -1.8026f   -8.3109u   -1.8337f

it shows that after Iin increase than 160uA the source-body diode of M1 and M3 turn on because voltage of v3 decrease over than diode conduction voltage and so after this, how much that Iin increase Id1 don't increase and according it the output current will be constant and remain current go through from two trace {vdd-->sb1-->Iin-->vss} and {vdd-->sb3-->Iin-->vss}.

so i think i must to increase the source-body diode conduction voltage, but how can i to do this? what do you think?
 

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