UC3842A, 43A UC2842A, 43A
Figure 7. Error Amp Open Loop Gain and
Phase versus Frequency
A VOL , OPEN LOOP VOLTAGE GAIN (dB)
100
80
Gain
60
40
Phase
20
0
120
150
100
1.0 k
10 k
100 k
1.0 M
180
10 M
VCC = 15 V
VO = 2.0 V to 4.0 V
RL = 100 K
TA = 25°C
Vth, CURRENT SENSE INPUT THRESHOLD (V)
0
30
60
90
φ
EXCESS PHASE (DEGREES)
,
1.2
VCC = 15 V
1.0
0.8
0.6
TA = 125°C
0.4
0.2
0
TA = –55°C
TA = 25°C
Figure 8. Current Sense Input Threshold
versus Error Amp Output Voltage
– 20
10
0
f, FREQUENCY (Hz)
2.0
4.0
6.0
VO, ERROR AMP OUTPUT VOLTAGE (V)
8.0
ISC, REFERENCE SHORT CIRCUIT CURRENT (mA)
∆
V ref , REFERENCE VOLTAGE CHANGE (mV)
Figure 9. Reference Voltage Change
versus Source Current
0
VCC = 15 V
Figure 10. Reference Short Circuit Current
versus Temperature
110
VCC = 15 V
RL
≤
0.1
Ω
90
–4.0
–8.0
–12
–16
–20
–24
0
20
40
60
80
100
120
Iref, REFERENCE SOURCE CURRENT (mA)
TA = 125°C
TA = 25°C
70
TA = 55°C
50
–55
–25
0
25
50
75
100
125
TA, AMBIENT TEMPERATURE (°C)
, OUTPUT VOLTAGE CHANGE (2.0 mV/DIV)
VCC = 15 V
IO = 1.0 mA to 20 mA
TA = 25°C
, OUTPUT VOLTAGE CHANGE (2.0 mV/DIV)
Figure 11. Reference Load Regulation
Figure 12. Reference Line Regulation
VCC = 12 V to 25 V
TA = 25°C
O
∆
V
2.0 ms/DIV
∆
V
MOTOROLA ANALOG IC DEVICE DATA
O
2.0 ms/DIV
5
ONSEMI [ ON SEMICONDUCTOR ]
