ssl1750 NXP Semiconductors, ssl1750 Datasheet - Page 8

• Manufacturer Part Number: ssl1750
• Description: Smps Control Ic For Led Drivers
• Manufacturer: NXP Semiconductors

NXP Semiconductors
SSL1750_1
Product data sheet
7.1.2 Supply management
7.1.3 Latch input
All internal reference voltages are derived from a temperature compensated and trimmed
on-chip band gap circuit. Internal reference currents are derived from a temperature
compensated and trimmed on-chip current reference circuit.
The pin LATCH is a general purpose input pin, which can be used to switch off both
converters. The pin sources a current, I
Switching of both converters is stopped as soon as the voltage on this pin drops below
1.25 V.
At initial start-up switching is inhibited until the voltage on pin LATCH is above
1.35 V (typ). No internal filtering is done on this pin. An internal Zener clamp of 2.7 V (typ)
protects this pin from excessive voltages.
Fig 5.
PROTECTION
PFCDRIVER
PFCSENSE
VINSENSE
FBDRIVER
VOSENSE
FBSENSE
FBCTRL
LATCH
Start-up sequence, normal operation, and restart sequence
V
V
I
HV
CC
out
CHARGING VCC
CAPACITOR
Rev. 01 — 15 September 2008
CONVERTERS
STARTING
OPERATION
NORMAL
O(LATCH)
soft start
soft start
PROTECTION
on the pin LATCH (typical 80 A).
SMPS control IC for LED drivers
RESTART
SSL1750
© NXP B.V. 2008. All rights reserved.
V
V
V
V
V
V
V
startup
th(UVLO)
trip
start(VINSENSE)
en(LATCH)
to(FBCTRL)
start(fb)
014aaa060
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