MC33560DTBR2G ON Semiconductor, MC33560DTBR2G Datasheet - Page 15

• Manufacturer Part Number: MC33560DTBR2G
• Description: IC INTERFACE PWR MANAGMT 24TSSOP
• Manufacturer: ON Semiconductor

Specifications of MC33560DTBR2G

• Applications: *
• Interface: *
• Voltage - Supply: *
• Package / Case: 24-TSSOP
• Mounting Type: Surface Mount
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: MC33560DTBR2GOS

complementary, and will shut the circuit off either if the
overcurrent is high enough to bring the CRDV
below the preset threshold, either after 160 ms (typ.)
only if the battery supply voltage is high enough to allow
normal operation (1.8 V).
of typically 20 ms to ensure stable operation. The current
detector is a comparator associated with two resistors: one
2.0 W attached to PGND and usually connected to analog
ground, and a 0.5 W attached to ILIM, usually connected to
ground through an external resistor to adjust the maximum
peak current. The voltage developed across this resistor
network is then compared to a 120 mV (typical) reference
voltage,
cycle−by−cycle peak current limitation by switching off the
low side transistor when the voltage exceeds 120 mV.
converter if current limitation is continuously detected
during 160 ms (typical). This allows normal operation with
high filtering capacitance and low peak current, even at
converter startup. As a result, a short circuit to ground on the
card connector or a continuous overcurrent is reported by
RDYMOD 160 ms (typical) after powerup.
card extraction and runs a powerdown sequence if card
power is still on when extraction occurs. An active pulldown
switch clamps CRDV
extraction is detected. The external capacitors will then be
discharged. With typical capacitor values of 10 mF and 47 nF
as indicated in the application schematic, the time needed to
discharge CRDV
The overcurrent and undervoltage protection features are
In addition, the DC−DC converter will be allowed to start
The undervoltage comparator has a hysteresis and a delay
The internal
Unexpected Card Extraction: The MC33560 detects
FEED
BACK CLOCK OFF
and
ILIMCOMP
the
CC
PWN
CC
to a voltage below 0.4 V can be
comparator
DIGITAL
VBAT
FILTER
ILIMCOMP
to GND within 150 ms (max) after
signal is monitored to stop the
ON /OFF
STOP
OVER TEMP
DETECTION
ON /OFF
COUNTER
Figure 22. DC−DC Converter Functional Block
output
LOGIC
AND
−
+
Low Side
120 mV
Switch
performs
L1
CC
CONVERTER
VBATOK
2 W
PGND
http://onsemi.com
output
FAULT
MC33560
ERROR
a
AMP.
RLIM (external)
0.5 W
ILIM
+
−
+
−
15
Rectifier Switch
RECTIFIER
CONTROL
resistors
Internal
UNDER VOLTAGE
estimated to less than 750 ms. The total time aftercard
extraction detection until CRDV
estimated to 900 ms (maximum). All smartcard connector
contacts will be deactivated before CRDV
This ensures that no electrical damage will be caused to the
smartcard under abnormal extraction conditions.
supply voltage to 3.0 V or 5.0 V at any time, before DC−DC
converter start, or during converter operation. When
switching from 3.0 V to 5.0 V, a 160 ms (typical) delay
blanks the undervoltage fault detection to allow filter
capacitor charging.
working modes:
Variable on−state and fixed frequency (typically 120 KHz)
for average to heavy loads.
Variable on−state and variable frequency for light loads.
connected to CRDV
the V
to increase stability.
filtering of card current spikes. Low values allow low startup
charging current. Care must be taken not to combine low
capacitor value with high current limiting, as this can
generate high ripple. Usual values range from 4.7 mF to
47 mF, depending on current limiting.
The choice of inductor L1 and resistor R4 is made by using
Figure 8 (5.0 V card) and/or Figure 9 (3.0 V card) on page 8:
DETECTOR
3.0 V/5.0 V Programming: It is possible to set the card
PWM: The free−running integrated oscillator has two
The frequency can be as low as a few kHz if no load is
The charging current of the timing capacitor is related to
Filtering Capacitor: A high value allows efficient
Selecting the External Components L1 and RLIM:
CRDGND
BAT
VREF
supply voltage, to allow better line regulation, and
ON /OFF
CC
.
CRDGND
CC
Active pull−down
reaches 0.4 V is then
switch
3V/5V
CC
CRDVCC
ON /OFF
deactivation.