tea1733p NXP Semiconductors, tea1733p Datasheet - Page 7

• Manufacturer Part Number: tea1733p
• Description: Greenchip Smps Control Ic
• Manufacturer: NXP Semiconductors

NXP Semiconductors
TEA1733P
Product data sheet
7.6 Duty cycle control (CTRL pin)
7.7 Slope compensation (CTRL pin)
7.8 Overpower timer (OPTIMER pin)
The PROTECT input can be used to create overvoltage detection and OTP functions.
A small capacitor can be connected to the pin if the protections on this pin are not used.
An internal clamp of 4.1 V (typical) protects this pin from overvoltages.
The output power of the converter is regulated by the CTRL pin. This pin is connected to
an internal 5.4 V supply using an internal 7 kΩ resistor.
The CTRL pin voltage sets the peak current which is measured using the ISENSE pin
(see
Section
A slope compensation circuit is integrated in the IC for CCM. Slope compensation
guarantees stable operation for duty cycles greater than 50 %.
If the OPTIMER pin is connected to capacitor C4 (see
situation is allowed. V
400 mV, the I
voltage on the OPTIMER pin reaches the V
OverPower Protection (OPP) is triggered (see
When the V
before the V
Fig 5.
Section
7.12). The maximum duty cycle is limited to 72 % (typical).
Overpower delay
V
prot(OPTIMER)
OPTIMER
prot(OPTIMER)
V
7.10). At a low output power the switching frequency is also reduced (see
IO(OPTIMER)
ISENSE
All information provided in this document is subject to legal disclaimers.
V
I
O
O
ctrl(Ipeak)
Rev. 6 — 15 February 2011
voltage is reached the device restarts. If the overload is removed
current (11 μA typical) is sourced from the OPTIMER pin. If the
voltage is reached, the converter will continue switching.
high load
(see
Figure
normal
load
1) is set by the CTRL. When V
prot(OPTIMER)
Figure
high load
5).
Figure
voltage (2.5 V typical) the
GreenChip SMPS control IC
3), a temporary overload
protection
TEA1733P
400 mV
V
014aaa930
prot(OPTIMER)
© NXP B.V. 2011. All rights reserved.
ctrl(Ipeak)
is above
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