ML4821
PRODUCT SPECIFICATION
Under Voltage Lockout, OVP and Current Limit
On power-up the ML4821 remains in the UVLO condition;
output low and quiescent current low. The IC becomes
operational when VCC reaches 16V. When VCC drops below
9V, the UVLO condition is imposed. During the UVLO
condition, the VREF pin is “off”, making it usable as a “flag”
for starting up a down-stream PWM converter.
OVP, Shutdown, and IC Bias
When the input to the OVP comparator exceeds VREF, the
output of the ML4821 is inhibited. The OVP input also
functions as a “sleep” input, putting the IC into the low
quiescent UVLO state when the OVP pin is pulled below
0.7V.
500
RT = 5kΩ
VRMS = 3V
400
300
200
100
0
0
100
200
300
400
SINE INPUT CURRENT (µA)
5.5
4.5
3.5
2.5
1.5
1.0
500
Figure 7. Gain Modulator Linearity.
ENABLE
VREF
9V
INTERNAL
BIAS
4.4V
LOGIC
POWER
VREF 16
VCC 15
Figure 8. Under-Voltage Lockout Block Diagram.
40
30
20
TA = 25°C
10
0
0
10
20
30
VCC SUPPLY VOLTAGE (V)
Figure 9. Total Supply Current vs. Supply Voltage.
0
–4.0
VCC = 15V
–8.0
–12
TA = –55°C
–16
TA = 125°C
–20
TA = 25°C
–24
0
20
40
60
80
100
120
IREF, REFERENCE SOURCE CURRENT (mA)
Figure 10. Reference Load Regulation.
8
REV. 1.0.2 6/19/01