ha16116fpj Renesas Electronics Corporation., ha16116fpj Datasheet - Page 10

• Manufacturer Part Number: ha16116fpj
• Description: Switching Regulator For Chopper Type Dc/dc Converter
• Manufacturer: Renesas Electronics Corporation.

HA16116FP/FPJ, HA16121FP/FPJ
2.3 Error Amplifier
Figure 2.3 shows an equivalent circuit of the error amplifier. The error amplifier on these ICs is configured
of a simple NPN transistor differential input amplifier and the output circuit of a constant-current driver.
This amplifier features wide bandwidth (f
feedback to be applied when the power supply is designed. Phase compensation is also easy.
Both HA16116 and HA16121 have a noninverting input (IN(+)) pin, in order to allow use of the channel 1
error amplifier for inverting control. The channel 2 error amplifier, on the other hand, is used for step-
down control in HA16116 and booster control in HA16121; so the channel 2 noninverting input is
connected internally to Vref.
3. Dead Band (DB) Duty and Soft Start Setting (common to both channels)
3.1 Dead Band Duty Setting
Dead band duty is set by adjusting the DB pin input voltage (V
connect two external resistors to the Vref of this IC so as to divide V
Note: V
Vref is typically 2.5 V. Select R
Rev.2.0, Sep.18.2003, page 10 of 33
V
V
Duty (DB) =
Here, T =
TH
TL
DB
: 1.0 V (Typ)
: 1.6 V (Typ)
IC internal V
= Vref
IN( )
IN(+)
f
OSC
1
V
V
R
IN
TH
TH
1
R
+ R
2
Figure 2.3 Error Amplifier Equivalent Circuit
V
V
2
DB
TL
1
(V)
and R
100 (%)
2
so that 1.0 V ≤ V
T
= 4 MHz) with open loop gain kept to 50 dB, allowing stable
80 A
This applies when V
If V
DB
< V
DB
TL
≤ 1.6 V.
, there is no PWM output.
DB
). A convenient means of doing this is to
40 A
DB
DB
(see figure 3.1).
> V
TL
.
E/O
To internal PWM
comparator