Datasheet

15Maxim Integrated
Active-Clamped, Spread-Spectrum,
Current-Mode PWM Controllers
MAX5974A/MAX5974B/MAX5974C/MAX5974D
Block Diagrams (continued)
DRIVER
1A/-0.65A
DEAD-TIME
CONTROL
11NDRV
SS16 CS9 CSSC8 COMP5 FB6 IN13 EN14
VC
PGND
DRIVER
0.5A/-0.3A
12AUXDRV
1DT 3 15 4
20% < D
MAX
< 80%
RT
DCLMP
FFB
SYNC
VB
30µA/
90µA
NDRV
BLANKING
PULSE
SS
VC
PGND
FFB COMP
V
CSAVG
DEAD TIME
NDRV
AUXDRV
POK
OSCILLATOR
DRIVER LOGIC
REVERSE I
LIM
LIMIT TURNS
OFF AUX IMMEDIATELY
PEAK I
LIM
COMP
400mV
2
DITHER/
SYNC
7GND 10PGND
VB
50µA/ -50µA
2V/400mV
10X
Q
SET
Q
CLR
S
COUNT 8
EVENTS
HICCUP
LATCH
115ns
BLANKING
5V
REGULATOR
ENABLE
1.215V
POK
VB
THERMAL
SHUTDOWN
UVLO
115ns
BLANKING
R
V
SS
< 150mV
REVERSE I
LIM
COMP
-100mV
2µA
10µA 2mA
POK
PWM
COMP
R1
2 x R1
VB
1.215V
VB
VB
g
M
VB
SLOPE
COMPENSATION
LOW-POWER UVLO
V
INUVR
= 16V (MAX5974C)
V
INUVR
= 8.4V (MAX5974D)
V
INUVF
= 7V
MAX5974C MAX5974D
18V