C
U R R E N T
-M
O D E
PWM C
O N T R O L L E R
SG1844/SG1845 Series
P R O D U C T D A T A B O O K 1 9 9 6 / 1 9 9 7
3
Copyright 2000
Rev. 1.4 4/00
P
R O D U C T I O N
D
A T A
S
H E E T
E L E C T R I C A L C H A R A C T E R I S T I C S
(Unless otherwise specified, these specifications apply over the operating ambient temperatures for SG1844/SG1845 with -55°C
≤
T
≤
125°C, SG2844/
SG2845 with -25°C
≤
T
≤
85°C, SG3844/SG3845 with 0°C
≤
T
≤
70°C, V
= 15V (Note 7), R
= 10k
, and C
T
= 3.3nF. Low duty cycle pulse testing
techniques are used which maintains junction and case temperatures equal to the ambient temperature.)
Reference Section
Output Voltage
Line Regulation
Load Regulation
Temperature Stability (Note 4)
Total Output Variation (Note 4)
Output Noise Voltage (Note 4)
Long Term Stability (Note 4)
Output Short Circuit
Oscillator Section
Initial Accuracy (Note 8)
Voltage Stability
Temperature Stability (Note 4)
Amplitude
Discharge Current
Parameter
Symbol
Test Conditions
T
J
= 25°C, I
O
= 1mA
12
≤
V
IN
≤
25V
1
≤
I
O
≤
20mA
Line, Load, Temp.
10Hz
≤
f
≤
10kHz, T
J
= 25°C
T
A
= 125°C, 1000hrs
V
N
SG3844/45
Units
Min. Typ. Max. Min. Typ. Max. Min. Typ. Max.
SG2844/45
4.95 5.00 5.05 4.95 5.00 5.05 4.90 5.00 5.10
6
20
6
6
25
6
0.2
0.4
0.2
4.90
5.10 4.90
50
50
5
25
5
-30
-100 -180
-30
-100 -180
V
20
25
0.4
5.10 4.82
6
6
20
25
0.4
5.18
mV
mV
mV/°C
V
μV
mV
mA
0.2
50
5
-100 -180
25
25
-30
T
J
= 25°C
12V
≤
V
CC
≤
25V
T
MIN
≤
T
A
≤
T
MAX
V
RT/CT
(Peak to Peak)
T
J
= 25°C
T
MIN
≤
T
A
≤
T
MAX
Error Amp Section
Input Voltage
Input Bias Current
Open Loop Gain
Unity Gain Bandwidth (Note 4)
Power Supply Rejection Ratio
Output Sink Current
Output Source Current
V
OUT
High
V
OUT
Low
V
COMP
= 2.5V
A
VOL
2
≤
V
O
≤
4V
T
J
= 25°C
12
≤
V
CC
≤
25V
V
VFB
= 2.7V, V
COMP
= 1.1V
V
VFB
= 2.3V, V
COMP
= 5V
V
VFB
= 2.3V, R
L
= 15K to gnd
V
VFB
= 2.7V, R
L
= 15K to V
REF
(Electrical Characteristics continue next page.)
PSRR
SG1844/45
47
52
.02
5
1.7
8.3
57
1
47
52
0.2
5
1.7
8.4
57
1
47
52
0.2
5
1.7
8.4
57
1
kHz
%
%
V
mA
mA
7.8
6.8
9.1
9.3
7.5
7.2
9.3
9.5
7.5
7.2
9.3
9.5
2.45 2.50 2.55 2.45 2.50 2.55 2.42 2.50 2.58
-0.3
-1
-0.3
65
90
65
90
0.7
1
0.7
1
60
70
60
70
2
6
2
6
-0.5
-0.8
-0.5
-0.8
5
6
5
6
0.7
1.1
0.7
V
1
-0.3
90
1
70
6
-0.8
6
0.7
-2
μA
dB
MHz
dB
mA
mA
V
V
65
0.7
60
2
-0.5
5
1.1
1.1
Supply Voltage Range
Output Current (Peak)
Output Current (Continuous)
Analog Inputs (Pin 2, Pin 3)
Error Amp Output Sink Current
Oscillator Frequency Range
Oscillator Timing Resistor
Oscillator Timing Capacitor
Operating Ambient Temperature Range:
SG1844/45
SG2844/45
SG3844/45
Note 3. Range over which the device is functional.
R
T
C
T
R E C O M M E N D E D O P E R AT I N G C O N D I T I O N S
(Note 3)
Parameter
Symbol
Units
Recommended Operating Conditions
Min.
Typ.
Max.
30
±1
200
V
A
mA
V
mA
kHz
k
μF
0
2.6
5
0.1
0.52
0.1
500
150
1.0
-55
-25
0
125
85
70
°C
°C
°C