tlpf-old%20=%20Clpf%20/%20gmlpf

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Original Offset Correction
tlpf-old Clpf / gmlpf
DC Gain gm1/(gmOC gm1) For 50dB attenuation,
need gmOC gt 317.2 gm1 Way too much power required
to do this!
Improved Offset Correction
tlpf Clpf(1 A) / gmlpf
DC Gain gm1/(AgmOC gm1) High-gain voltage
stage A allows lower power Can also use miller
effect across A to slow down LPF smaller cap
needed
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Frequency Response _at_ Q 2, f90 10kHz

• lt 1dB Variation from unity -- 70 Hz to 3kHz
• HF Attenuation gt 51dB (gt50dB)

• Attenuation at 0.1Hz 51.5dB (gt50dB)
• LF Rolloff 40 Hz (lt50Hz)

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Stability -- Stepping Vref

• Peak Overshoot 100 (not good wanted lt 10!)
• Settling to 5 in 30ms (lt 50ms exceeds spec by
  over 20)

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DC Behavior

• Flat for 300mV (gt100mV exceeds spec by over 20)

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Transient and Linear Range
Time (ms)

• Power-on time lt 1ms

• Noise 320mV, Vmds 160mV _at_ Q 2
• _at_f90, Vinmax gt 0.64Vpp, DR gt 72dB (gt60dB, exceeds
  spec gt 20)

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• Area lt ¼ of Chip
• Total Power 20mW (lt 30mW exceeds spec by gt
  20)
• Uses Common Centroid for all diff pairs, current
  mirrors, and cascode pairs.