有人care過bandgap可能存在不止1個degenerate points(stable points)嗎？

hi.china59

有人care過bandgap可能存在不止1個degenerate points(stable points)嗎？
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The degenerate point of Bandgap reference circuit
" f: L! J6 i$ k$ ^; WQ:有人care過bandgap可能存在不止1個degenerate points(stable points)嗎？
A: We do care the degenerate points of a bandgap reference circuit. The bandgap reference circuit needs a more effective startup circuit than those usually adopted. The crossing (degenerate) points are much less defined. Please read the attached bandgap degenerate points.pdf

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Low Voltage Bandgap Reference Circuit
/ I! R8 b- i0 j. [/ _Patent number: 6489835
Filing date: Aug 28, 2001
  \. w* x) r$ C" g7 K8 U/ ?Issue date: Dec 3, 2002
Inventors: Quan Yu, Edwin Chan
1 J! R; ]/ d' X3 P0 JAssignee: Lattice Semiconductor Corporation

5 y; [/ e5 F  bBanba et al, in "A CMOS Bandgap Reference Circuit with Sub-1-V Opeation", discloses a bandgap reference circuit that can operate at supply voltage down to about 1V.  This configuration needs two additional resistors, RA and RB, to generate CTAT currents.  However, these two resistors will result in more than one opeating point, especially when the drain voltages of PMOS transistors, drops below ΔVbe(i.e., when the two bipolar devices are turns off).  Existence of more than one opeating point makes the start-up circuit very complex, or requires an additional circuit to gurantee achievement of a proper operating point.  Without such a circuit, the risk of having an undesired operating point is high.
9 Y) T9 v9 h* Q5 _This configuration differs from Banba's circuit in several ways.
1. Only one resistor, RC, is added to provide an CTAT current, rather than need two such resistors.
2. Only one non-zero initial current, and this system will move to this point after power-up.
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5 f  k; x! U3 ^. zLow_voltage_bandgap_reference_circuit.pdf
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pkf690801

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cgxcgx2005

good
% e8 t% c' _% H% Z) p6 h7 n) lthanks for sharing.......

fish_20

good!!! good!!!
6 r& ?, [: F2 M8 E  ?- G  Tthanks for sharing!!!

hoodlum

哇!!!從來沒想過這個問題
謝謝大大分享
趕快下載!!!!

oric

這是個很重要的問題~之前有遇過
0 U8 u7 V5 A7 J( O3 o. e& `謝謝樓主的分享~

lchuang

完全沒想過......................

zhangyunwu5555

回復 1# hi.china59
a noval question thanks for your sharing!

li202

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dentice

非常感謝分享 之前做bandgap 時從來沒考慮過此問題

lhyi

This is really something to think about, thanks

gasol

好問題+好回答, 感謝大大

alkla

是個好問題!不過是個成熟技術電路~~應該避免落在臨界範圍

hitxiaojun

还从来没有遇到过呢。看看

hitxiaojun

还从来没有遇到过呢。看看

mailhwm

回復 1# hi.china59

6 J1 \* P% o  {1 {+ f. q
) b. t: w1 e# t; ~若有好的 startup 來控制
$ S3 E6 Y% ?: S8 E7 c7 p  }8 Z2 T還會有這問題嗎
看不到附件

u9513349

I want this very important circuit for bandgap,thxs for your show!!!

kevinlin1

谢谢啊，正在设计它！！！

chian

3Q  very much
, @! O! z* n; S7 S/ C& @看看有什磨內容囉!!!!!!

starfish311

重要，重要，重要~~~~~~~~~~~~