
FA7700V, FA7701V
3
Pulse width modulation (PWM) section (FB terminal voltage and duty cycle)
Item
Symbol
Test condition
Min.
Typ.
Max.
Unit
FB 0% threshold
VFB0
Duty cycle = 0%
0.560
0.660
0.760
V
FB 50% threshold
VFB50
Duty cycle = 50%
0.880
V
Maximum duty cycle
FA7700
DMAX1
RT=100k
, f=50kHz
85
90
95
%
DMAX2
RT=22k
, f 185kHz
83
88
93
%
DMAX3
RT=3k
, f 1MHz
80
86
92
%
FA7701
DMAX
100
%
Error amplifier section (IN- terminal, FB terminal)
Item
Symbol
Test condition
Min.
Typ.
Max.
Unit
Reference voltage
VB
IN- terminal, FB terminal:
0.863
0.880
0.897
V
Shorted (voltage follower)
Input current
IIN–
-500
+500
nA
VB line regulation
VBLINE
Vcc=2.5 to 20V
±1
±5mV
VB variation with temperature
VBTC1
Ta=–30 to 25
°C
±0.3
%
VBTC2
Ta=25 to 85
°C
±0.3
%
Open loop gain
AVO
70
dB
Unity gain bandwidth
fT
1.5
MHz
Output current
Source
IOHE
FB terminal=VREF– 0.5V
–220
–160
–100
A
Sink
IOLE
FB terminal=0.5V
3
6
12
mA
Oscillator section (Frequency set by RT terminal)
Item
Symbol
Test condition
Min.
Typ.
Max.
Unit
Oscillation frequency
fosc
RT=22k
155
185
215
kHz
Line regulation
fLINE
Vcc=2.5 to 20V
±0.1
%
Variation with temperature
fTC1
Ta=–30 to 25
°C, 50k to 1MHz
±2%
fTC2
Ta=25 to 85
°C, 50k to 1MHz
±3%
s Electrical characteristics (Ta=25C, VCC=6V, RT=22k
)
Internal bias section (REF terminal voltage)
Item
Symbol
Test condition
Min.
Typ.
Max.
Unit
Output voltage
VREF
REF terminal source current
2.16
2.23
2.30
V
IREF=0mA
Line regulation
VLINE
Vcc=2.5 to 20V, IREF=0mA
±2
±14
mV
Load regulation
VLOAD
IREF=0 to 2mA
±2
±12
mV
Variation with temperature
VTC1
Ta=–30 to 25
°C
±0.3
%
VTC2
Ta=25 to 85
°C
±0.3
%
Undervoltage lock-out section (VCC terminal voltage)
Item
Symbol
Test condition
Min.
Typ.
Max.
Unit
ON threshold
VCCON
2.07
2.30
V
OFF threshold
VCCOF
1.60
1.93
V
Hysteresis voltage
VCCHY
0.04
0.14
0.24
V
Variation with temperature
VCCHY
Ta= –30 to 25
°C
+0.2
mV/
°C
Ta= 25 to 85
°C
–0.2
mV/
°C