CS5171, CS5172, CS5173, CS5174
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3
ELECTRICAL CHARACTERISTICS (2.7 V< V
CC
< 30 V; Industrial Grade: −40°C < T
J
< 125°C;
Commercial Grade: 0°C < T
J
< 125°C; For all CS5171/2/3/4 specifications unless otherwise stated.)
Characteristic
Test Conditions Min Typ Max Unit
Positive and Negative Error Amplifiers
FB Reference Voltage (CS5171/3 only)
V
C
tied to FB; measure at FB 1.246 1.276 1.300 V
NFB Reference Voltage (CS5172/4 only) V
C
= 1.25 V −2.55 −2.45 −2.35 V
FB Input Current (CS5171/3 only) FB = V
REF
−1.0 0.1 1.0
mA
NFB Input Current (CS5172/4 only) NFB = NV
REF
−16 −10 −5.0
mA
FB Reference Voltage Line Regulation
(CS5171/3 only)
V
C
= FB − 0.01 0.03 %/V
NFB Reference Voltage Line Regulation
(CS5172/4 only)
V
C
= 1.25 V − 0.01 0.05 %/V
Positive Error Amp Transconductance
I
VC
= ± 25 mA
300 550 800
mMho
Negative Error Amp Transconductance
I
VC
= ± 5 mA
115 160 225
mMho
Positive Error Amp Gain (Note 2) 200 500 − V/V
Negative Error Amp Gain (Note 2) 100 180 320 V/V
V
C
Source Current FB = 1.0 V or NFB = −1.9 V, V
C
= 1.25 V 25 50 90
mA
V
C
Sink Current FB = 1.5 V or NFB = −3.1 V, V
C
= 1.25 V 200 625 1500
mA
V
C
High Clamp Voltage FB = 1.0 V or NFB = −1.9 V;
V
C
sources 25 mA
1.5 1.7 1.9 V
V
C
Low Clamp Voltage
FB = 1.5 V or NFB = −3.1 V, V
C
sinks 25 mA
0.25 0.50 0.65 V
V
C
Threshold Reduce V
C
from 1.5 V until switching stops 0.75 1.05 1.30 V
Oscillator
Base Operating Frequency
CS5171/2, FB = 1 V or NFB = −1.9 V 230 280 310 kHz
Reduced Operating Frequency CS5171/2, FB = 0 V or NFB = 0 V 30 52 120 kHz
Maximum Duty Cycle CS5171/2 90 94 − %
Base Operating Frequency CS5173/4, FB = 1 V or NFB = −1.9 V 460 560 620 kHz
Reduced Operating Frequency CS5173/4, FB = 0 V or NFB = 0 V 60 104 160 kHz
Maximum Duty Cycle CS5173/4 82 90 − %
NFB Frequency Shift Threshold Frequency drops to reduced operating frequency −0.80 −0.65 −0.50 V
FB Frequency Shift Threshold Frequency drops to reduced operating frequency 0.36 0.40 0.44 V
Sync/ Shutdown
Sync Range
CS5171/2 320 − 500 kHz
Sync Range CS5173/4 640 − 1000 kHz
Sync Pulse Transition Threshold Rise time = 20 ns 2.5 − − V
SS Bias Current SS = 0 V
SS = 3.0 V
−15
−
−3.0
3.0
−
8.0
mA
mA
Shutdown Threshold − 0.50 0.85 1.20 V
Shutdown Delay 2.7 V ≤ V
CC
≤ 12 V
12 V < V
CC
≤ 30 V
12
12
80
36
350
200
ms
ms
2. Guaranteed by design, not 100% tested in production.