UC3842B, 43B UC2842B, 43B
Figure 5. Error Amp Small Signal
Transient Response
2.55 V
VCC = 15 V
AV = –1.0
TA = 25°C
20 mV/DIV
3.0 V
Figure 6. Error Amp Large Signal
Transient Response
VCC = 15 V
AV = –1.0
TA = 25°C
2.50 V
2.5 V
2.45 V
0.5
µs/DIV
2.0 V
1.0
µs/DIV
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
Figure 8. Current Sense Input Threshold
versus Error Amp Output Voltage
VCC = 15 V
1.0
0.8
0.6
TA = 125°C
0.4
0.2
0
TA = –55°C
TA = 25°C
– 20
10
0
f, FREQUENCY (Hz)
2.0
4.0
6.0
VO, ERROR AMP OUTPUT VOLTAGE (V)
8.0
I SC , REFERENCE SHORT CIRCUIT CURRENT (mA)
Figure 9. Reference Voltage Change
versus Source Current
∆
Vref , REFERENCE VOLTAGE CHANGE (mV)
0
Figure 10. Reference Short Circuit Current
versus Temperature
110
VCC = 15 V
– 4.0
– 8.0
–12
–16
VCC = 15 V
RL
≤
0.1
Ω
90
TA = –55°C
TA = 125°C
70
– 20
– 24
TA = 25°C
60
0
20
40
80
100
120
50
– 55
– 25
0
25
50
75
100
125
Iref, REFERENCE SOURCE CURRENT (mA)
TA, AMBIENT TEMPERATURE (°C)
MOTOROLA ANALOG IC DEVICE DATA
5
/
ÄÄÄÄ
ÄÄÄÄ
ÄÄÄÄ
ÄÄÄÄ
ÄÄÄ
ÄÄÄ ÄÄÄÄ
ÄÄÄÄ
ÄÄÄÄ
MOTOROLA [ MOTOROLA, INC ]
