tda8031hl-c107 NXP Semiconductors, tda8031hl-c107 Datasheet - Page 29

• Manufacturer Part Number: tda8031hl-c107
• Description: Usb Smart Card Reader Otp Or Rom
• Manufacturer: NXP Semiconductors

Philips Semiconductors
8.2
The supply to the chip is delivered by the USB-bus (pins
V
8.2.1
A power switch control is used in order to limit the inrush
current when plugging the reader into the bus. The main
decoupling capacitor is connected to the output of this
power switch control (pin V
8.2.2
The output voltage of the 3.3 V linear regulator is used for:
If this voltage is used within the application, the current
should not exceed 10 mA.
For stability reasons, a 1 F low ESR decoupling capacitor
is needed between the output of the regulator (V
the specific regulator ground (DGND).
2003 Jul 04
handbook, full pagewidth
DDU
Powering-up the microcontroller and the ISO7816
UART
It is the reference voltage for the signalling pull-up
resistor connected to pin D+.
USB smart card reader (OTP or ROM)
and UGND).
SUPPLY
P
3.3 V
OWER SWITCH CONTROL
REGULATOR
DD
).
clock
reset
low
Fig.7 DC-to-DC converter.
up
DDD
N drive
P drive
) and
29
For programming the EPROM of the TDA8030; TDA8031,
by applying a logic 1 to pin CPROG it will disable the
regulator, so that the microcontroller will be powered-up at
5 V.
8.2.3
In case of a 5 V card, the card buffers are supplied by an
inductive DC-to-DC converter.
In case of a 3 or 1.8 V card, the DC-to-DC converter is
transparent and the card buffers are then supplied directly
by V
The external components for the DC-to-DC converter
should be an inductance of 6.8 H, a low ESR capacitor of
1 F and a Schottky diode (type BAT54).
The power efficiency is approximately 85% up to
I
start-up phase to avoid spurious supply drop-outs.
The DC-to-DC converter is transparent for a 3 V card.
CC
V DD
= 55 mA. The current is limited at 100 mA during the
DD
LX
.
V ref
DC-
TO
-DC
V UP
CONVERTER
MGU887
TDA8030; TDA8031
Product specification