TEA1532 Philips Semiconductors, TEA1532 Datasheet - Page 6

• Manufacturer Part Number: TEA1532
• Description: GreenChip SMPS control IC
• Manufacturer: Philips Semiconductors

Philips Semiconductors
9397 750 13113
Preliminary data sheet
7.1 Start-up, mains enabling operation level and undervoltage lock out
7.2 Supply management
7.3 Current control mode
In fixed frequency continuous conduction mode, the internal oscillator determines the start
of the next converter stroke.
In both operating modes, a cycle skipping mode is activated at very low power (standby)
levels.
Refer to
voltage via pin DRAIN. Supply capacitor C
current source to a level of about 4 V or higher, depending on the drain voltage. Once the
drain voltage exceeds the V
current source will continue charging capacitor C
Figure
passes the V
output voltage reaches its intended level and the IC supply from the mains voltage is
subsequently stopped for high efficiency operation (green function).
The moment the voltage on pin V
stops switching and enters a safe restart from the rectified mains voltage. Inhibiting the
auxiliary supply by external means causes the converter to operate in a stable,
well-defined burst mode.
All (internal) reference voltages are derived from a temperature compensated, on-chip
band gap circuit.
Current control mode is used for its good line regulation behavior.
The on-time is controlled by the internally inverted pin CTRL voltage, which is compared
with the primary current information. The primary current is sensed across an external
resistor. The driver output is latched in the logic, preventing multiple switch-on.
The internal control voltage is inversely proportional to the external pin CTRL voltage, with
an offset of 1.5 V. This means that a voltage range from 1 V to approximately 1.5 V on
pin CTRL will result in an internal control voltage range from 0.5 V to 0 V (a high external
control voltage results in a low duty cycle).
Fig 6. The V
1. The IC will activate the power converter as soon as the voltage on pin V
Figure 10
start
sense(max)
level. The IC supply is taken over by the auxiliary winding as soon as the
and
voltage as a function of V
Figure
Rev. 01 — 28 May 2004
V
sense(max)
0.52 V
25 mV
m
(mains-dependent operation-enabling level), the start-up
11. Initially, the IC is self supplying from the rectified mains
CC
drops below V
(typ)
1 V
VCC
(at pin 1) is charged by the internal start-up
CTRL
VCC
1.5 V
(typ)
UVLO
.
(switch S1 will be opened); see
(undervoltage lock out), the IC
GreenChip II SMPS control IC
Cycle
skip
active
© Koninklijke Philips Electronics N.V. 2004. All rights reserved.
coa016
V
CTRL
TEA1532
CC
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