LTC3499_15 Datasheet, PDF (12/16 Pages) Linear Technology – 750mA Synchronous Step-Up DC/DC Converters with Reverse-Battery Protection

LTC3499/LTC3499B
APPLICATIONS INFORMATION
There is a resultant gain increase with a phase lag which
makes it difficult to compensate the loop. At heavy loads
the right half plane zero can occur at a relatively low
frequency. The loop gain is typically rolled off before the
RHP zero frequency.
The typical error amp compensation is shown in Figure 3,
following the equations for the loop dynamics:
( ) ^fPOLE1~
1
2 • π • 10e6 • C_C1
which is extremely close to DC.
( ) ^fZERO1=
1
2 • π • R_Z • C_C1
( ) ^{fPOLE2 =}
1
2 • π • R_Z • C_C2
V_OUT
6
ERROR AMPLIFIER
1.22V
R1
FB
7
R2
VC
8
R_Z
C_C2
C_C1
3499 F03
Figure 3: Typical Error Amplifier Compensation
3499fc
12