TDA8035HN Datasheet, PDF (7/32 Pages) NXP Semiconductors – Smart card interface externally by a resistor bridge

NXP Semiconductors
TDA8035HN
Smart card interface
8. Functional description
Remark: Throughout this document the ISO 7816 terminology conventions have been
adhered to and it is assumed that the reader is familiar with these.
8.1 Power Supply
Power supply voltage V_DDP should be in the range from 2.7 to 5.5 V
All interface signals with the system controller are referenced to V_DD(INTF). All card
contacts remain inactive during powering up or powering down.
Internal regulator VREG should be in the range of 1.8 V
After powering the device, OFFN remains Low until CMDVCCN is set High and PRESN is
Low .
During power off, OFFN falls Low when V_DDP is below the threshold voltage falling.
The frequency of the internal oscillator Foscint used for the activation sequences is put in
low frequency mode in order to save power consumption as long as CMDVCCN is kept at
high level (card not activated).
This device includes DC/DC converter to generate the 5 V, 3 V or 1.8 V card supply
voltage (Vcc). The DC/DC converter should be supplied separately by Vddp and Gndp.
The DC/DC converter operates as a voltage tripler, doubler or follower according to the
respective values of Vcc and Vddp.
The operating mode is as follows (see Figure 3):
• Vcc = 5 V & Vddp > 3.8 V ; voltage doubler
• Vcc = 5 V & Vddp < 3.6 V; voltage tripler
• Vcc = 3 V & Vddp > 3.8 V; voltage follower
• Vcc = 3 V & Vddp < 3.6 V; voltage doubler
• Vcc = 1.8 V & Vddp > 3.8 V; voltage doubler
• Vcc = 1.8 V & Vddp < 3.6 V; voltage tripler
TDA8035HN
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 1.0 — 19 April 2011
© NXP B.V. 2011. All rights reserved.
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