MAX8741EAI+T Maxim Integrated, MAX8741EAI+T Datasheet - Page 9

• Manufacturer Part Number: MAX8741EAI+T
• Description: Current & Power Monitors & Regulators 500kHz Multi-Out Pwr Supply Controller
• Manufacturer: Maxim Integrated

Specifications of MAX8741EAI+T

• Rohs: yes
• Product: Power Monitors
• Supply Voltage - Max: 30 V
• Supply Voltage - Min: 4.2 V
• Input Voltage Range: 4.2 V to 30 V

SSOP
500kHz Multi-Output Power-Supply Controllers
10
11
12
13
14
1
2
3
4
5
6
7
8
9
PIN
TQFN
29
30
31
10
11
12
1
2
3
4
5
7
8
9
_______________________________________________________________________________________
(MAX8742)
(MAX8741)
(MAX8742)
(MAX8741)
TIME/ON5
12OUT
SECFB
STEER
RESET
NAME
CSH3
SYNC
CSH5
CSL3
CSL5
GND
SKIP
V
FB3
REF
FB5
DD
with High Impedance in Shutdown
Current-Sense Input for the 3.3V SMPS. Current-limit level is 100mV referred to CSL3.
Current-Sense Input. Also serves as the feedback input in fixed-output mode.
Feedback Input for the 3.3V SMPS. Regulates at FB3 = REF (approximately 2.5V) in
adjustable mode. FB3 is a dual-mode input that also selects the 3.3V fixed output-
voltage setting when connected to GND. Connect FB3 to a resistor-divider for
adjustable-output mode.
12V/120mA Linear-Regulator Output. Input supply comes from V
GND with 1µF (min).
Logic-Control Input for Secondary Feedback. Selects the PWM that uses a transformer
and secondary feedback signal (SECFB):
Supply Voltage Input for the 12OUT Linear Regulator. Also connects to an internal
resistor-divider for secondary winding feedback and to an 18V overvoltage shunt
regulator clamp.
Secondary Winding Feedback Input. Normally connected to a resistor-divider from an
auxiliary output. SECFB regulates at V
Regulation Loop section). Connect to V
Oscillator Synchronization and Frequency Select. Connect to V
connect to GND for 333kHz operation. Can be driven at 400kHz to 583kHz for external
synchronization.
Dual-Purpose Timing Capacitor Pin and ON/OFF Control Input. See the Power-Up
Sequencing and ON/ OFF Controls section.
Low-Noise Analog Ground and Feedback Reference Point
2.5V Reference Voltage Output. Bypass to GND with 1µF (min).
Log i c- C ontr ol Inp ut that D i sab l es Id l e M od e w hen H i g h. C onnect to G N D for nor m al use.
Active-Low Timed Reset Output. RESET swings GND to V
32,000 clock-cycle delay following power-up.
Feedback Input for the 5V SMPS. Regulates at FB5 = REF (approximately 2.5V) in
adjustable mode. FB5 is a dual-mode input that also selects the 5V fixed output-
voltage setting when connected to GND. Connect FB5 to a resistor-divider for
adjustable-output mode.
C ur r ent- S ense Inp ut for the 5V S M P S . Al so ser ves as the feed b ack i np ut i n fi xed - outp ut
m od e, and as the b ootstr ap sup p l y i np ut w hen the vol tag e on C S L5/V
Current-Sense Input for the 5V SMPS. Current-limit level is 100mV referred to CSL5.
STEER = GND: 3.3V SMPS uses transformer
STEER = V
L
: 5V SMPS uses transformer
FUNCTION
SECFB
L
if not used.
= 2.5V (see the Secondary Feedback
L
. Goes high after a fixed
Pin Description
L
DD
for 500kHz operation;
L
. Bypass 12OUT to
i s > 4.5V .
9