Texas Instruments Evaluation Board for the LM5039 LM5039EVAL/NOPB LM5039EVAL/NOPB 데이터 시트
제품 코드
LM5039EVAL/NOPB
30112704
Trace 1 (C1) Output Voltage
Trace 2(C2): Voltage on the ACL Capacitor
Trace 3 (C4): Voltage at the center-point of the half-bridge capacitor divider
FIGURE 3.
The LM5039 evaluation board is configured to be in constant
current limiting. To configure the board for hiccup mode
restart, remove the zero ohm resistor from the RES pin to the
AGND and install a 4700pF capacitor from the RES pin to the
AGND. The RES capacitor should be selected such that the
time taken for the RES capacitor to reach 2.5V is greater than
the time taken for the average current mode control circuit to
be in control. This will ensure that center-point of the half-
bridge capacitor is balanced. Figure 5 illustrates a balanced
half-bridge capacitor divider at the inception of a hiccup mode
restart. While Figure 6 shows the same over multiple hiccup
mode restarts. The RES capacitor should be selected such
that the time taken for the RES capacitor to reach 2.5V and
hence start the hiccup mode is greater than the time taken for
the ACL pin to get into control.
current limiting. To configure the board for hiccup mode
restart, remove the zero ohm resistor from the RES pin to the
AGND and install a 4700pF capacitor from the RES pin to the
AGND. The RES capacitor should be selected such that the
time taken for the RES capacitor to reach 2.5V is greater than
the time taken for the average current mode control circuit to
be in control. This will ensure that center-point of the half-
bridge capacitor is balanced. Figure 5 illustrates a balanced
half-bridge capacitor divider at the inception of a hiccup mode
restart. While Figure 6 shows the same over multiple hiccup
mode restarts. The RES capacitor should be selected such
that the time taken for the RES capacitor to reach 2.5V and
hence start the hiccup mode is greater than the time taken for
the ACL pin to get into control.
30112705
FIGURE 4.
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