TDA8354Q Datasheet, PDF (4/16 Pages) NXP Semiconductors – Full bridge current driven vertical deflection output circuit in LVDMOS

Philips Semiconductors
Full bridge current driven vertical deflection
output circuit in LVDMOS
Preliminary specification
TDA8354Q
PINNING
SYMBOL
V_o(guard)
V_i(M)
V_i(con)
V_P(B)
V_o(B)
GNDB
V_flb
GNDA
V_o(A)
V_P(A)
I_i(neg)
I_i(pos)
I_i(comp)
PIN
DESCRIPTION
1 guard output voltage
2 measuring resistor input
3 conversion resistor input
4 supply voltage B
5 output voltage B
6 ground B
7 flyback supply voltage
8 ground A
9 output voltage A
10 supply voltage A
11 input power-stage (negative);
includes I_i(bias) signal bias
12 input power-stage (positive);
includes I_i(bias) signal bias
13 damping resistor compensation
current input
handbook, halfpage
Vo(guard) 1
Vi(M) 2
Vi(con) 3
VP(B) 4
Vo(B) 5
GNDB 6
TDA8354Q
Vflb 7
GNDA 8
Vo(A) 9
VP(A) 10
Ii(neg) 11
Ii(pos) 12
Ii(comp) 13
MGL462
FUNCTIONAL DESCRIPTION
The vertical driver circuit is a bridge configuration.
The deflection coil is connected between the output
amplifiers, which are driven in phase opposition.
The differential input circuit is current driven. The input
circuit is special intended for direct connection to driver
circuits which deliver symmetrical current signals, but is
also suitable for asymmetrical currents. The current to
voltage conversion is done by the external resistor (R_con)
connected between the output of the input conversion
stage and output stage B. This voltage is compared with
the output current through the deflection coil measured as
voltage across R_M, which provides internal feedback
information. The relationship between the differential input
current and the output current is defined by:
2 × I_i(diff) × R_con = I_coil × R_M The output current is
adjustable from 0.5 A (p-p) to 3.2 A (p-p) by varying R_con.
The maximum input current is 800 µA peak for each pin.
The minimum input current should be 50 µA.
Flyback supply
The flyback voltage is determined by an additional supply
voltage V_flb. The principle of operating with two supply
voltages (class G) makes it possible to fix the supply
voltage V_P optimum for the scan voltage and the second
supply voltage V_flb optimum for the flyback voltage. Using
this method, very high efficiency is achieved. The supply
voltage V_flb is almost totally available as flyback voltage
across the coil, this being possible due to the absence of a
coupling capacitor (not necessary, due to the bridge
configuration). The very short rise and fall time of the
flyback switch is >400 V/µs.
Protection
The output circuit has protection circuits for:
• Die temperature control
• Overvoltage of output stage A.
The die has been glued to the metal block of the package. If the metal
block is not insulated from the heat sink, the heat sink may only be
connected directly to pins 6 and 8.
Fig.2 Pin configuration.
1998 Sep 03
4